Science and Religion, Again

In a post from 2012, I wrote the following as part of a discussion about reconciling science and religion:

Too often the defender of reconciliation acts as though his job is done as soon as he has tossed off a logically possible scenario that includes both God and evolution.

This was specifically in response to an interview with philosopher Elliott Sober, in which he breathlessly reported his finding that science could not absolutely rule out the possibility that God was guiding the mutations in the course of evolution. Adorably, he seemed to think this represented a genuine contribution toward reconciling science and religion. My point in reply was that bare logical possibility was not the issue. A successful reconciliation requires plausibility as well, and neither theistic evolutionists, nor the atheist philosophers who sometimes wade in, have had much success in that regard.

I have expressed similar sentiments many times at this blog, but I have always assumed that the targets of my criticism would object to my characterization. Perhaps I was wrong, since we now have Massimo Pigliucci explicitly writing this:

Here is a second highly indicative quote from Blackford: “Coyne makes clear that he is not talking about a strict logical inconsistency. Rather, incompatibility arises from the radically different methods used by science and religion to seek knowledge and assess truth claims.”

Ah, so it turns out that science and religion are, in fact, logically compatible (not sure why the clause “strict” is necessary here, something either is or is not logically consistent with something else). I could declare victory and graciously leave the room at this point, but I'm not done yet.

The context is that Massimo is replying to a review by Russell Blackford of Jerry Coyne's book Faith Versus Fact.

I was taken aback by this. He not only thinks he can declare victory at this point, but he's even snide about it. But Massimo, I think, is just being silly. Who, exactly, does he think he is declaring victory over? Who has ever claimed that there is a logical contradiction between religion in general and science? The only ones I can think of who might have endorsed such a claim are philosophers (like J. L. Mackie) who have defended the logical form of the argument from evil. Is that who Massimo has in mind? Russell and Jerry obviously didn't think they were making a concession here, so why is Massimo pretending otherwise?

Massimo's essay is quite long. It is a mix of reasonable points and weak points, but ultimately I think there's a bad error underlying many of his claims. He frequently writes as though there is a clean distinction between the factual assertions made by a religion and the religion's teachings about morality and values. This is wrong, but I will save discussion of that point for a separate post.

Instead, let me make my own views clear.

The question, “Are science and religion compatible?” is ill-posed. “Religion” (even if you limit it just to Christianity) means so many different things to different people that it is pointless to generalize. “Compatible” is also incredibly vague, as this little spat between Massimo and Russell shows. What Russell takes as an obvious and trivial assertion Massimo takes as an admission of defeat. Plainly, people are talking past each other.

If we use a more modest definition, and take compatibility to mean that a perfectly rational and well-informed person could simultaneously accept both science and even a robust, evangelical sort of Christianity, then I think science and religion are compatible. I would point to someone like Keith Miller, who has written eloquently on this. I entirely disagree with everything he believes, but I don't think he's being irrational or worse.

But there's a catch. I do think it's mighty difficult to reconcile science with certain very commonly held religious beliefs, so much so that I think the critics of theistic evolution have by far the better end of the argument. There's always enough vagueness in religious assertions, and enough limitations on what we can know, that I think a theistic evolutionist can avoid charges of outright irrationality. But the fact remains that the world as revealed by science sure looks different from the world as traditionally described by Christianity. Put as succinctly as possible, science claims that human beings are an accidental by-product of millions of years of vicious evolutionary bloodsport. Christianity claims that we are created in the image of God by an omnipotent being of perfect goodness. It is logically possible that those are two sides of the same coin, but they are not obviously so.

There's an entire industry devoted to defending theistic evolution. There's a reason that so many scholars must write at book length just to defend the bare possibility that evolution and Christianity can both be true. These defenses, which amount to little more than armchair philosophizing, are typically based on assertions that are far more implausible than anything the creationists are saying.

I have elaborated on these points elsewhere so I won't belabor them here. The bottom line is that talk of logical compatibility is just an asinine distraction. Religion as it is actually practiced (as opposed to the ivory tower version often discussed by philosophers and theologians) is typically based on factual assertions that are strongly challenged by science. An acceptable reconciliation requires not just a possible way of defusing the challenge, but a plausible way as well. Such a reconciliation is very hard to come by, and requires harder work than Massimo seems willing to provide.

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If the assertion, “Science and religion are incompatible,” simply means, “It is highly unreasonable to accept simultaneously the claims of modern science and the claims of traditional Christianity,” then I agree with it. The trouble is that the word “incompatible” is vague. People often take it…

Agree with a plenty of this but you say, “'Religion' means so many different things to different people that it is pointless to generalize" -- the same holds for "science." It is not some monolith but a spectrum across psychology, biology, physics, engineering, etc.; even their underlying structures or methodologies are NOT generalizable nor consistent as purported. From the opposite angle you don't deal here with the contention of many these days that "science" is itself just another religion (I don't agree with that, but do understand where it stems from and why it is hard to dispel).
And as you say even the word "compatible" is vague. I tire of these science/religion arguments because so much of it is just semantics, and as you also write at one point, "Plainly, people are talking past each other."

“Are science and religion compatible?” is ill-posed. “Religion” (even if you limit it just to Christianity) means so many different things to different people that it is pointless to generalize...

...There’s always enough vagueness in religious assertions, and enough limitations on what we can know, that I think a theistic evolutionist can avoid charges of outright irrationality.

This is why I think it's better to limit the argument to specific fact claims and methods. Then it's up to the religious person to declare/decide whether their religion includes those things or not. So, for example, we can say that the (provisional, inductive) findings of science are that humans can't resurrect, can't walk on water, can't turn water into wine. That scientifically we are not justified in believing we have a soul (or three souls, or seven souls, or any other number). That there was no single male-female pair from which all current humanity descends, and no global flood. That the earth is about 4.5 billion years old, and that we evolved from earlier species over millions of years as did every other species on the planet.

Moreover, when it comes to methodologies, we can say that the (provisional, inductive) findings of science is that the method of revelation does not work. It cannot be distinguished from the null hypothesis, and thus beliefs arising from this method gain no credibility from the method itself; their credibility will instead depend on independent reasons to believe them (such as empirical evidence etc.). Thus if the only reason you have for believing something is revelation, that belief is not scientifically justified.

Now, does that make someone's specific religion and religious beliefs compatible or incompatible with science? Every believer can answer that question for themselves, depending on what beliefs they hold. Like Jason, I suspect that the answer for someone like Ken Ham will be very different from the answer given by someone like Ken Miller or Barry Lynn.

I don't know that this applies to all religions (because I don't know all religions), but the compatibility issue that bothers me is this basic difference: science - don't fool yourself (do controlled experiments, check to see if they are repeatable, use peer review, use statistical analysis to try to eliminate coincidences); religion - fool yourself (if prayer doesn't work 99 times and then works once, prayer works).

A lot of philosophers (the ones I hear about anyway) are enablers of the latter attitude with their trivial point that "you can't prove that somebody's god doesn't exist" (it could be hiding).

There isn't a lot of absolute proof in science either. (There's probably a philosopher somewhere willing to argue that the luminiferous ether might exist.) The real-world test is, does it work? Religion (in terms of producing the miracles it claims, for those religions which do) does not work.

Example: in medieval Europe, when the Christian Church dominated the culture and prayer was the basic remedy for all ills, the infant (0-5 years old) mortality rate was between 30 and 50%. Yet recently a creationist commenter at another blog claimed that his prayer healed one of his children from a deadly disease.

Science and religion can well be made compatible, but I don't think the god most religious people want to believe in can be made compatible with reality. For instance, a god could sneak in beneficial mutations without us being able to detect them, but the same god could also easily remove harmful ones. Giving that said god chooses not to do so speaks volumes. Either it is a massive bastard or more likely just doesn't exist.

By Michael Fugate (not verified) on 21 Jan 2016 #permalink

Just listening from the back.

By sean samis (not verified) on 21 Jan 2016 #permalink

... science could not absolutely rule out the possibility that God was guiding the mutations in the course of evolution.

It's quite a step down from "the greatest conceivable being" to "indistinguishable from random chance."

By Bayesian Bouff… (not verified) on 21 Jan 2016 #permalink

A successful reconciliation requires plausibility as well,

Plausibility is rarely a criterion for religious claims. Much of religion does hinge upon implausible claims , in turn that makes the argument that a religious claim is possible but not plausible, futile.

Ah, so it turns out that science and religion are, in fact, logically compatible

Heh - is the Christian God logically compatible with itself in the first place ? Can omnipotence logically be an attribute of any being ? Can God do what is logically impossible ? - if not the question of religion (atleast christianity in a narrow sense) being logically compatible with anything doesnt arise.
But there is a subset of non-atheists (Coyne being one of them , and you are not) who do make stronger claims about incompatibility and they shouldn't then gloss over it as if its trivial.

By Deepak Shetty (not verified) on 21 Jan 2016 #permalink

Heh – is the Christian God logically compatible with itself in the first place ?

Indeed. IMO 'infinite/perfect justice' and 'infinite/perfect mercy' are logically incompatible concepts. The first requires the entity sitting in judgment to exactly (perfectly) match the punishment to the crime. The second requires that the entity sitting in judgment intentionally choose a punishment less than what is deserved. You logically can't do both at once.

@Jason R:

If we use a more modest definition, and take compatibility to mean that a perfectly rational and well-informed person could simultaneously accept both science and even a robust, evangelical sort of Christianity, then I think science and religion are compatible.

I think it's important to emphasize the concept of psychological compartmentalization, here. Can an intelligent person compartmentalize their scientific thinking when doing science, and religious thinking when being religious? Yes, obviously. People can compartmentalize all sorts of different ways of thinking.

I would point to someone like Keith Miller, who has written eloquently on this.

I am pretty sure that you mean Kenneth Miller, here.

I entirely disagree with everything he believes,

This is the kind of careless hyperbole that leads to unhelpful and uncharitable criticism.

I am confident that your disagreement with his beliefs is largely restricted to those of his beliefs that are specifically religious, not everything, or even close to everything.

but I don’t think he’s being irrational or worse.

I might be willing to accuse him of being irrational in his religious thinking, and about the inconsistency between his scientific thinking and his religious thinking. But this is distinct from saying that he's completely irrational, which I would agree that he's not.

By Owlmirror (not verified) on 21 Jan 2016 #permalink

Some theologians have tried to reconcile infinite knowledge, goodness and power with universal reconciliation. But then, what it's the point?

God's effect on the world seems to be statistically indistinguishable from luck...only science has improved our odds. Prayer certainly hasn't.

BTW, Plantinga is big on saying god works on the quantum level. That's why he/she/it is indistinguishable from chance, see _Where the Conflict Really Lies: Science, Religion, and Naturalism_. Its hooey all the way down.

Theists seem to feel a need to have a religion to legitimize their values...which are always changing. Why is charging interest on loans OK now that we live in a capitalist country? Not too long ago, it was taught you'd burn in hell.

I agree with Eric in @2:

"This is why I think it’s better to limit the argument to specific fact claims and methods."
And the specific fact claim that is my favourite is the Resurrection. Science says dead people don't come alive; christianity says it happened at least once. The only sensible reaction apologists can give is "science must shut up, 'cuz god". That is an admission of incompatibility.

Owlmirror--

Ken Miller and Keith Miller are different people. Ken Miller is a biologist at Brown and is a Roman Catholic. Keith Miller is a geologist at Kansas State University and an Evangelical Christian.

Keith Miller is the editor of this book, which is what I was referring to in the post.

I see two things which doom compatibilty: random variations cannot, by definition, be guided to produce a predetermined outcome. They can be subjected to conditions in the environment which favour some sets of intermediate results over others but science holds that those conditions, too, are random consequences. This precludes any intentional guidance and that precludes any intelligent deity behind the scenes.

Second, in science, "human" is not definitively defined--nor can it be. We can only make arbitrary and subjective distinctions around the borders between what we call humans and their nearest biological neighbours, or "cousins". And, as we are still evolving, if we assert that God "created 'man' at any definite time now past, then we are bound to either eventually evolve away from any even remote resemblance to that kind of creature or become extinct as a "species". But, on reflection, it is hard to see what the difference is between the two. If we're accidentally evolving, there us no room left for intelligent intervention by a diety--even remote intervention.

By proximity1 (not verified) on 22 Jan 2016 #permalink

I see two things which doom compatibilty: random variations cannot, by definition, be guided to produce a predetermined outcome....

By definition is untrue. We can certainly think of random processes that produce very predicable outcomes. The game of craps is a good example: the dice rolls are, for all intents and purposes, truly random. But the casino can predictably make money off the game. One could imagine a superintelligent being rigging up mutational odds such that certain paths are just enough more likely that, over statistically long series of iterations, they become practical certainties. Do we live in that world though? We don't appear to. It would be up to the defenders of that proposition to identify how to test it. Moreover, given the distribution of different types of life on earth, if the system is rigged, it's rigged to produce prokaryotes, not single-celled or multi-celled eurkaryotes.

Eric, I your analogy, the dice are not a random, I dependent variable in the priduction of complex random inputs and their ensuing outputs. They are instead a predetermined and highly restricted range of outcomes. If we accept them as being the entire living environment in which nature's evolutionary processes work, then we are still left with what nature presents: a set of outcomes which are *probabilistic* but NOT Reliably predictable. In human births, for example, the great majority are healthy live born infants. But only a fool would tell a prospective mother that she's sure to deliver a normal healthy infant. This isn't that predictable.

By proximity1 (not verified) on 22 Jan 2016 #permalink

To restate my point, if a factor us introduced deliberately then it's not a randomly-occurring feature of the environment and, thus, does not conform to a natural condition.

The actual odds against *our own unique life form* (I.e. "humans"--which remains indefinable) resulting with near certainty from evolutionary processes suggests an inconceivably large number of "universe events"--each one defined as a complete Cycle from "BIG BANG" inception to full expansion to then closing with a space-time collapse which provokes the next Big Bang, and so on before ever producing the first chain of events with a 50/50 chance of arriving at the genus Homo.

In that case, people are worshipping a soulless robotic thing for their God.

By proximity1 (not verified) on 22 Jan 2016 #permalink

Re 17

It appears that the space/time collapse may not occur due to the existence of dark energy.

By colnago80 (not verified) on 22 Jan 2016 #permalink

If this is the sole universe event then you have to imagine the odds of randomly producing accidents "designed" to "eventually" result in (undefined) "humans" on the first and only "attempt". Thus even more incredible. A God that operates via Darwinian evolution is still an "intelligent design" theory. It is unscientific.

By proximity1ti (not verified) on 22 Jan 2016 #permalink

@ 18 : would you please cite a source/paper? Thank you.

By proximity1ti (not verified) on 22 Jan 2016 #permalink

The arrow of time flies in both directions.

By Wesley Dodson (not verified) on 22 Jan 2016 #permalink

"I see two things which doom compatibilty: random variations cannot, by definition, be guided to produce a predetermined outcome. They can be subjected to conditions in the environment which favour some sets of intermediate results over others but science holds that those conditions, too, are random consequences. This precludes any intentional guidance and that precludes any intelligent deity behind the scenes."
Incorrect as soon as you let omnipotence go. The Flying Spaghetti Monster and polytheistic belief systems don't have this compatibility problem. However the causal abrahamistic gods indeed do, as Einstein already noticed.

Not that this is much worth arguing about, but apparent randomness in nature, like everything else in science that I can think of, is not absolutely proven fact but only strongly supported by good evidence. Someone who refuses to accept that evidence could, for example, reason as follows:

I could write a program, say a game program, in which some events are random (and in fact I do, some unpredictable randomness is a good feature in any universe, to avoid what I call stability traps) - but as the programmer, I can also go into program memory with a hex-editor and change a random result to one that I specify. And if I don't do it too often or do it in places where game-players won't notice it, they will never know it happened.

So such arguments fall back into my incompatibility problem as I explained it previously: the incompatibility between those who are willing to follow the evidence and those who aren't.

Mutations are thought to be random in relationship to the organism's need - not that they can't be caused deterministically.

By Michael Fugate (not verified) on 22 Jan 2016 #permalink

@ 21 & 24:

I don't understand what you want to get at by those comments.

Still waiting for a reference for the post on dark matter. And the same would be welcomed for time's two-way arrow.

By proximity1 (not verified) on 23 Jan 2016 #permalink

JimV @ 23

You could write a programme. Where is the evidence that God did?

Without that, it is superfluous to assume it. Per Wm. Ockham

By proximity1 (not verified) on 23 Jan 2016 #permalink

The question of “reconciling science and religion” should not arise at all. Science is completely wrong and religions are all same and all correct.

Laws of nature are the only truth. Science has never given any law of nature nor has answered any question related to the laws of nature or objects of nature. Take Newton’s first law for example, which we have studied in our high school classes – an object will move continuously in a straight line with constant velocity. This is a completely wrong theory. No one has seen such an object on earth or in space.

Take another example – do we know why eclipse happens? You would say, yes science has said – objects rotate around each other. But why do they rotate? Otherwise they will fall on each other. Then again why will they fall - because of gravity? Isn’t gravity and fall are same words? Thus science tried to confuse people by coining a complicated word like gravity. But the idea is - science has never answered any question. Therefore reconciliation is a wasted effort. For more examples take a look at https://theoryofsouls.wordpress.com/

Vedas talk about the following laws of nature: soul theory, yogic power, reincarnation, destiny, universal memory, eternal recurrence, birth-maturity-death for all objects etc. There is no God in Vedas. If you look carefully you will find all of these laws are there in Bible also. Reincarnation was there in Bible, but was removed later. Destiny is clearly stated in Bible. Yogic power is also mentioned in Bible. Many examples of very high level yogic powers are discussed in Judaism.

Clearly destiny and God are incompatible. Laws of nature cannot contradict. Bible has a Vedic interpretation, which says no God, no concept of morality, no one is sinner etc. – these are against destiny law. Bible and Hinduism also have money power interpretations, which are their main stream interpretations. Mainstream interpretations are false, since money is false, as money is not an object of nature, and does not obey the laws of nature.

Proximity, you seem to be misreading what some people are writing, which makes further explanations seem futile. Example: dark energy, not dark matter, is what seems to be causing the expansion of the universe to accelerate rather than decelerate, which in turns means it will not collapse (see Wikipedia, or simply search on "dark energy"). And by arguing with my previous comment based on evidence rather than logical proof (which Occam's Razor is not, by the way - many theists think it supports them*), you prove its point.

* I prefer to use Mario's Sharp Rock, myself: among competing hypotheses, yada, yada, yada, always chose the most humble one.

Errata (wishing comments could be edited): "which in turns" should be "which in turn", and "prove its point" should be "support its point".

Jason Rosenhouse @#13: Thanks for the clarification. I apologize for my confusion.

Do you discuss Keith Miller or his ideas anywhere else? I used the search box for this blog, at least, and found only passing references in a couple of posts from 2009, about the paleontological convention in Cincinnati (and your visit to the Creation "Museum").

By Owlmirror (not verified) on 23 Jan 2016 #permalink

@proximity1:

@ 18 : would you please cite a source/paper [for "It appears that the space/time collapse may not occur due to the existence of dark energy."]? Thank you

This is a very basic summary of the work for which Saul Perlmutter won the 2011 Nobel Prize, which basically means that the expansion of the universe is accelerating, which in turn means that your statement @#17 about "universe events [...] closing with a space-time collapse which provokes the next Big Bang" is no longer a viable scenario.

Inside the document are further references:

S. Perlmutter et al. (1998), presentation at the January 1998 Meeting of the American Astronomical Society, Washington, D.C., LBL Report Number LBL-42230; referenced in B.A.A.S.,
Volume 29, page 1351 (1997); astro-ph/9812473

S. Perlmutter et al., Astrophysical Journal, 517:
565-586 (1999); astro-ph/9812133

You can go to arxiv.org and search on the last part of the reference (e.g, paste "astro-ph/9812473" into the search box) to find the specific reports and papers, or go to scholar.google.com, which will not only allow you to find the references, but also those works that cite them.

Note that there are/were those who dispute Perlmutter's finding; if I understand them correctly, they argue that a vast portion of the local galactic group might be expanding at an accelerated rate, rather than the entire universe itself. I think this is very much a minority viewpoint, and not currently what is supported by further observations.

By Owlmirror (not verified) on 23 Jan 2016 #permalink

@ 31:
So you answer for the person who posted @ 18?

I'd prefer to have his/her responses.

And, yes, not everyone (scientists) agrees with the paper you cite and , from what I see, they've not an extreme minority--not that it would matter even if they were. I science the minority view could be the correct ine. For your reading see Bunn and Hogg (2009) @ arxiv.org : 0808:1081; Kinematic Origin of the Cosmological Redshift.

I'll try and read the paper you cited. At Wikipedia's page on cosmology, which kf the many theories do you hold as bedt? Cyclical or some other?
And how is this relevant to my point:
Compatibilty must reconcile an intelligent guidance with our present data and science. No one here has attempted this, let alone done it. Nor has anyone explained in brief layman's terms how he justifies a view if a universe which is non-cyclical, infinite and had one or more discrete space-time points of origin but shall continue without a termination.

Anyone? How do you reconcile these?

By proximity1t (not verified) on 24 Jan 2016 #permalink

@proximity1:

@ 31:
So you answer for the person who posted @ 18?

Sure. You asked for citations to support a scientific claim. I provided some.

The point of a citation isn't who offers it, but what it supports.

I’d prefer to have his/her responses.

Why, exactly?

For your reading see Bunn and Hogg (2009) @ arxiv.org/abs/0808.1081 ; Kinematic Origin of the Cosmological Redshift.

[arxiv cite slightly edited for accessibility]

As best I can tell, this paper does not disagree with Perlmutter's findings, but focuses specifically on the physical interpretation thereof with respect to photons. There is nothing there that even hints that the universe might not continue expanding forever.

As for cosmology -- I think eternal inflation is plausible, but I understand that cosmologists recognize that plausibility isn't enough.

A popular work that covers many of these topics is From Eternity to Here, by cosmologist Sean M. Carroll.

And how is this relevant to my point:
Compatibilty must reconcile an intelligent guidance with our present data and science. No one here has attempted this, let alone done it.

I agree that there is no sign of intelligent guidance in our universe. I don't think anyone who responded to you about the single issue of an oscillating expanding/contracting universe thinks otherwise. But that claim in your original comment is no longer seen as being scientifically viable.

Nor has anyone explained in brief layman’s terms how he justifies a view if a universe which is non-cyclical, infinite and had one or more discrete space-time points of origin but shall continue without a termination.

I am not quite sure what you're asking, nor how it is relevant to the first two sentences you wrote, but I will point again at Sean M. Carroll's book that I mentioned above.

By Owlmirror (not verified) on 24 Jan 2016 #permalink

A popular work that covers many of these topics is From Eternity to Here, by cosmologist Sean M. Carroll.

Maybe I'll read it. I read his The Particle at the End of the Universe.

RE : "There is nothing there that even hints that the universe might not continue expanding forever."

My memory may be faulty. But as I recall, they don't subscribe to a limitless expansion theory. I'd have to re-read it and in fact I intend to do that. I also found several interesting papers on these topics and I think it would be interesting to discuss them--but off topic in this thread. I think this has already strayed way off the beam from what's necessary to deal with the matter of compatibility in worhippers' views of their God or their religion's doctrines about God.

No one, by the way, addressed my second objection--which I think is the stronger of the two: there is no definitive and objective definition of what constitutes a "human" and I argue that this is because such a definitive definition is not possible--this is relevant here because these religions posit a God who has created the Universe and all that is in it and who is supposed to have a relation (Diety-to-worshiper) with human-kind, supposedly His supreme creation.

If we're evolving according to Darwin's evolution (and its succeeding aspects), and if we survive long enough--i.e. we don't become extinct--then we're bound to evolve out of all resemblance to what this Gid is supposed to have created. What then? (Logically, long before that point could arrive, the foundations of these antique belief systems should have broken down under the weight of contrary reason and evidence.)

Me: "I’d prefer to have his/her responses."
You: "Why, exactly?"

Well, that way I can tell what the person with whom I'd been corresponding actually thinks--and on what he or she has based an assertion. Suppose, for example, that he'd never read the paper you cited. That wouldn't mean the paper itself isn't pertinent or interesting, but it would mean that his claim is probably not based on his having read or relied on it. Right? It's also a matter of courtesy and respect. He made the claim. I think it's only right that I look to him for his source.

-----------

Personally, I think the infinite expansion of the Universe is a logical impossibility--as I do with all things "infinite" except, notably, a special case: in the realm of mathematics, which is an abstract art, a theoretical philosophy, not a natural science, there are "infinte series,"--it's a manner of speaking, a theoretical construct, and not something either real or even realistic. Only in theory are numners infinite--to the extent that we can always posit another term in any finite series and, in theory, do this without end. In fact, we cannot do it without end. Because the universe and everything in it (theoretical abstractions apart) is finite.

------------------
Papers I downloaded to read (in no particular order):

Giovanni MACCHIA -- "Expansion of the Universe and Spacetime Ontology" Humana.Mente Issue 13 / April 2010

Nick Kaiser: arXiv: 1312.1190 [astro -ph. CO] 4 Dec. 2013

Jean-Christophe HAMILTON : "What Have We Learned From Observational Cosmology?" [ arXiv : 1304.4446 ] [astro-ph. CO] 16 April 2013

Bunn and Hogg : "Kinematic Origins of Cosmological Redshift" (cited above in this thread)

By proximity1 (not verified) on 25 Jan 2016 #permalink

I see two things which doom compatibilty: random variations cannot, by definition, be guided to produce a predetermined outcome. They can be subjected to conditions in the environment which favour some sets of intermediate results over others but science holds that those conditions, too, are random consequences. This precludes any intentional guidance and that precludes any intelligent deity behind the scenes.

I'm late to the game, but this isn't quite true, depending on how you're defining "random." A random number generator in a computer game reliably produces numbers corresponding to a given distribution, but with a few exceptions they are themselves completely deterministic. Given that a seed always produces the same sequence, it's possible to reseed the algorithm in the middle somewhere to produce a desired outcome which yet does not at all disrupt the random distribution or appearance of randomness to someone who doesn't know the sequence has been diddled.

And with a sufficiently sophisticated random number generator, there's no way for an observer to distinguish a pseudorandom generator from a real one. This means that God could predict the deterministic sequential outcome of any initial condition in relation to the environment it's going to be employed in, and choose the one that leads to the sequence of events he's willing to live with. An observer in the universe would have no means of determining whether this was all truly random or only pseudorandom; God will have sufficiently covered his tracks.

There's no evidence that would lead anyone to suspect this, of course — it's a post-hoc rationalization of a pre-existing belief — but this illustrates is how ridiculously easy it is to come up with logical compatibility.

Second, in science, “human” is not definitively defined–nor can it be. We can only make arbitrary and subjective distinctions around the borders between what we call humans and their nearest biological neighbours, or “cousins”. And, as we are still evolving, if we assert that God “created ‘man’ at any definite time now past, then we are bound to either eventually evolve away from any even remote resemblance to that kind of creature or become extinct as a “species”. But, on reflection, it is hard to see what the difference is between the two. If we’re accidentally evolving, there us no room left for intelligent intervention by a diety–even remote intervention.

This is all true, and uncontroversial in biology and among many philosophers (Dennett makes this argument in Darwin's Dangerous Idea). There are still ways to weasel out, though, for instance by appealing to the Aristotelian/Thomist essence-accident distinction. There's a surprisingly popular just-so story that has been making the rounds for the last few years (I remember seeing it first with Edward Feser, but I'm sure it's not original to him). The story goes like this: humans evolved from earlier primates. But an animal that is physically identical with a human but which has no rational soul isn't truly human; this was the case with the earliest homo sapiens. Then God endowed two of those early homo sapiens with souls, and ensured that any of their descendants would also have souls. Ensouled humans could mate with unensouled homo sapiens, and their offspring would be ensouled (this accounts for the genetic bottleneck problem). From then on, however humans evolve in the future, as long as they have a rational soul, they will still be truly human.

The "truly" in "truly human" is doing a ton of conceptual work here, but it is logically possible, however fantastic and unsupported by evidence. Why anyone would believe it is beyond me.

This is why Massimo's victory dance about mere logical compatibility is so disappointing.

By Another Matt (not verified) on 25 Jan 2016 #permalink

@proximity1:

No one, by the way, addressed my second objection-which I think is the stronger of the two: there is no definitive and objective definition of what constitutes a "human" and I argue that this is because such a definitive definition is not possible-this is relevant here because these religions posit a God who has created the Universe and all that is in it and who is supposed to have a relation (Diety-to-worshiper) with human-kind, supposedly His supreme creation.

If we're evolving according to Darwin's evolution (and its succeeding aspects), and if we survive long enough-i.e. we don't become extinct-then we're bound to evolve out of all resemblance to what this Gid is supposed to have created. What then?

Well -- inasmuch as I am not a theist, I don't particularly care about this. But, for the sake of argument, I'll point out that "out of all resemblance to what this Gid is supposed to have created" might well refer to physical form, but not necessarily to mental attributes. So a sophistimacated theist might not be bothered by this. You'll have to get a response from a theist to see if they agree, though.

Me: "I'd prefer to have his/her responses."
You: "Why, exactly?"

Well, that way I can tell what the person with whom I'd been corresponding actually thinks-and on what he or she has based an assertion. Suppose, for example, that he'd never read the paper you cited. That wouldn't mean the paper itself isn't pertinent or interesting, but it would mean that his claim is probably not based on his having read or relied on it. Right? It's also a matter of courtesy and respect. He made the claim. I think it's only right that I look to him for his source.

This doesn't really make sense, though. The commentator might have seen an episode of Nova (or some other science-popularizing show ), or read a popular science article or blog posting on the topic. Yet whatever the source was, it would have referenced the actual work by the astrophysicists and cosmologists. It's at worst a few steps removed from the original work. But the original work is still out there as the basis for the later references.

Personally, I think the infinite expansion of the Universe is a logical impossibility-[...]

Hm. I think most cosmologists would be fine with "indefinite" rather than "infinite". I think it depends on whether protons are stable. If they are not, then matter will decay as it spreads further apart, and eventually everything will be weak radiation.

If protons are stable, then everything that spreads apart will nevertheles retain structure; structure that will eventually become cold and dark.

In fact, we cannot do it without end. Because the universe and everything in it (theoretical abstractions apart) is finite.

Technically, there are a finite amount of particles in the observable universe. But this does not mean that the universe cannot continue expanding indefinitely.

By Owlmirror (not verified) on 25 Jan 2016 #permalink

@ 35: RE : ” A random number generator in a computer game reliably produces numbers corresponding to a given distribution,* but with a few exceptions they are themselves completely deterministic. Given that a seed always produces the same sequence, it’s possible to reseed the algorithm in the middle somewhere to produce a desired outcome which yet does not at all disrupt the random distribution or appearance
of randomness to someone who doesn’t know the sequence has been diddled.
And with a sufficiently sophisticated random number generator, there’s no way for an observer to distinguish a pseudorandom generator from a real one. This means that God could predict the deterministic sequential outcome of any initial condition in relation to the environment it’s going to be employed in, and choose the one that leads to the sequence of events he’s willing to live with."*

There are a number of things wrong (*) with your presentation. But none of that really matters since the point hrre is that neither Jewish, Christian nor Muslem theologies subscribe to such a hypothesis. On the matter of compatibilty of worship, all these doctrines presuppose an omnipotent diety which detrmines the course and fate of the physical universe and everything in it.

By proximity1 (not verified) on 26 Jan 2016 #permalink

"Technically, there are a finite amount of particles in the observable universe. But this does not mean that the universe cannot continue expanding indefinitely"

"Technically"? Yes, when considered carefully it does mean that the Universe cannot "continue expanding
indefinitely. " Think about it.

By proximity1 (not verified) on 26 Jan 2016 #permalink

@ 35 : RE "Then God endowed two of those early homo sapiens with souls, and ensured that any of their descendants would also have souls. Ensouled humans could mate with unensouled homo sapiens, and their offspring would be ensouled (this accounts for the genetic bottleneck problem). From then on, however humans evolve in the future, as long as they have a rational soul, they will still be truly human."

Same problem as the previous cited excerpt: none of the relevant theologies subscribe to such a hypothesis. The point here isn't about whether some far-fetched scenario could be dreamed up to reconcile the Jewish, Christian and Muslem distinct concepts of God as thought by their various believers. It's that these theologies do not hold to any such hypotheses, The sacred texts tell their believers what God is and what He is "all about." And these pictures are irreconcilable--from the point of view of any consistent reasonableness.

By proximity1 (not verified) on 26 Jan 2016 #permalink

Technically, there are a finite amount of particles in the observable universe. But this does not mean that the universe cannot continue expanding indefinitely”

“Technically”? Yes, when considered carefully it does mean that the Universe cannot “continue expanding
indefinitely. ” Think about it.

I'm thinking...and I don't see what you're getting at. AFAIK the lambda metric expansion of space is not dependent on particle count or density. Gravity's impact is of course dependent on mass and mas distribution, and can slow this expansion down, but (a) the universe is already not dense enough to stop the expansion, and (b) the actual relationship I've described above is the exact opposite of the one you're implying (which appears to be something like: you think when particles run out, expansion stops).

So, could you explain in more detail why you think lambda will drop to zero as particle count or density goes down?

@ 40 : It's off-topic --but I think it's an interesting question. So I'll be as brief as I, an not-very tutored layman, can be.

If we suppose a finite number of particles (atoms or subatomic particles, whatever the smallest discrete particle may be) in a continually-expanding universe, then, eventually those particles, each one of them, is isolated in a measureless expanse of space. Even this way of expressing it is woefully inadequate to the true scope of the separation. "Infinitely large" cannot, logically, "expand." Does the contradiction not strike you?

Whether we refer to "time" or to "space" or to a four-vector, infinity is a, excuse the pun, "non-starter"--but it is, literally. Infinity can have no end-points, neither an "origin" nor, of course, as is more readily accepted, a "termination." Furthermore, there is no "locality" possible in infinity for various reasons, including that it cannot have an "in", an "inside" nor an "inner-ness." As a boundlessness --the word extension, too, is inappropriate here--it defies any location(s)--indeed, it defies "discrete-ness" in the most utter sense conceivable. Infinity cannot have any qualities. It's an absolute.

These are not "my original work. See, e.g. Great Ideas of Modern Mathematics and Great Ideas and Theories of Modern Cosmology both by Jagjit Singh.

By the way, the Giovanni Macchia paper ( http://www.thehumanmind.eu/PDF/Issue13_Paper_Macchia.pdf ) is quite interesting.

By proximity1 (not verified) on 26 Jan 2016 #permalink

@41 - I don't see any actual argument there. Okay, so eventually particle density drops below 1 per cubic whatevers. So what? How does that stop the expansion? What force or mechanism are you proposing stops lambda from operating? You have claimed a logical impossibility which is much stronger than an empirical hypothesis, but you don't even have an empirical hypothesis as far as I can see. You have only incredulity about the notion of infinity.

Furthermore, there is no “locality” possible in infinity for various reasons, including that it cannot have an “in”, an “inside” nor an “inner-ness.”

So what? QM is nonlocal, and relativity did away with any objective frame of reference. Your statements might be problems for a Newtonian universe, but we don't live in a Newtonian universe. QM is also an example of why your claim about infinity in @34 is wrong - there are wavefunctions that go out to infinity in terms of radial or spatial extent. So it's not just an abstract mathematical concept: the best, most tested and confirmed scientific theory of the day predicts that (some) particle wavefunctions have infinite spatial extent. And if you suppose some limited or finite radial extent to those wavefunctions, that will lead to a worse prediction of where you will measure the particle to be. Finite extent is a less accurate description.

Is the thought of infinite spatial wavefunctions absurd to human minds? Yes (to most humans). But there are lots of things about QM that appear absurd to us, and given the choice between my intuitional understanding of the world and what QM predicts, I would be that QM is more right than my intuition - and more right than any feeling of incredulity or absurdity I get at the thought of infinite wavefunctions or quantum erasers or particles traveling multiple paths simultaneously. My intuitions were evolved to deal with a macro-sized scale where these phenomenon are hidden/washed out by statistics. Your and my feelings of incredulity are nothing more than our limited brains trying to deal with phenomena those brains and senses did not evolve to cope with. If they lead to answers which differ from what the best science can tell us happens on scales wildly different from our biological one, we should abandon the intuitions, not abandon the science.

Excuse me but it was from the strictly mathematical point of view that Einstein "needed" a cosmological constant. Without one his equations couldn't be squared with a static universe. Then it turned out, upon further analysis, that both his constant and his assumed static universe were mistaken. Still, it made--or seemed to make--(a precious few) equations solvable.

Neither intuition nor mathematical rigour, alone, are sufficient to keep us from error. Sometimes both of them together aren't sufficient, either.

We don't know enough yet to have a good clear concept of exactly how physical reality is related to space time at the most fundamental level. We cannot neatly relate all the most firmly held parts of theory into a mathematically consistent whole. So conventional "work-arounds " to get on with research. Experience shows that sometimes the math can be made to work --giving us the wrong answer in physical reality.

By proximity1 (not verified) on 26 Jan 2016 #permalink

We don’t know enough yet to have a good clear concept of exactly how physical reality is related to space time at the most fundamental level.

Fair enough. Now describe to me how you started from 'we don't know...' and arrived at your conclusion of 'it's not infinite and won't expand forever.' Because that very much sounds like you're saying you know enough to rule out a couple of possibilities, and I want to know on what basis you rule them out.

And yes, Einstein goofed, and it was pure serendipity that his goof turned out to be a very accurate model of the universe. Nevertheless, LambdaCDM is currently the best model we have. So attacking its pedigree does nothing to undermine the fact that it fits the data, and you still haven't provided me any reason to think that the metric expansion represented by lambda (a) will change as particle density goes down, or (b) go to zero at some point in the future.

@42 : "I don’t see any actual argument there."

To be fair, you should see a brief argued view, yes. What you don't see is mathematical equations or formulae. Once more, I don't think this is the place for an extended discussion of cosmology.

By proximity1 (not verified) on 26 Jan 2016 #permalink

#32:"Nor has anyone explained in brief layman’s terms how he justifies a view if a universe which is non-cyclical, infinite and had one or more discrete space-time points of origin but shall continue without a termination.

Anyone? How do you reconcile these?"

#46: "I don’t think this is the place for an extended discussion of cosmology."

The latter is what I thought on seeing the former. I suggest moving the discussion to "Starts With A Bang".

@ 44 & 45 :

Well, it seems to me that our options are few. Either this reality is unique and sprang up ab nihil X bn. years ago for the first and only time or it has always existed--evolving or not--in which case it is infinite in duration (yet another conceptual contradiction in terms) or it is a serial set of cyclical events (my preference) which punctually recur in one or in varied forms--my shorthand is "universe events" for the recurring cycles.

Logically, in a universe which is not a vacuum--where matter/energy flows--eternal existence would imply that there is either a renewing cycle going on or there would be infinite distances (another conceptual contradiction) separating all discrete material bodies or energy forms. Thus, each photon would trace an isolated path through limitless empty space where neither any other photon or material is ever met. If, "underneath" this void there was some fundamental space-time framework, there'd be nothing to notice it and no means to detect it.

By proximity1 (not verified) on 26 Jan 2016 #permalink

@ 47 :

Be my guest. But I don't think that blog's host would patiently suffer this discussion--reason enough for me to avoid his blog. But you and others can try it.

By proximity1 (not verified) on 26 Jan 2016 #permalink

Logically, in a universe which is not a vacuum–where matter/energy flows–eternal existence would imply that there is either a renewing cycle going on or there would be infinite distances (another conceptual contradiction) separating all discrete material bodies or energy forms

No, there is no contradiction in the term 'infinite distance.' You just don't like it. Moreover I think the weak anthropic principle answers your claim quite easily. Whatever the long-term state of the universe is predicted to be, humans capable of analyzing the universe are going to exist only at those times when things like suns, planets, and humans are capable of forming, not after. If only ~100 billion years out of an infinite time span is capable of supporting life, then any life observing the universe will be in that 100 billion years, not before or after. So the fact that we don't see such a 'dismembered' universe is perfectly rational and easily explained - not a paradox or argument against infinite time/space at all.

I think the weak anthropic principle answers your claim quite easily. Whatever the long-term state of the universe is predicted to be, humans capable of analyzing the universe are going to exist only those times when things like suns, planets, and humans are capable of forming, not after. If only ~100 billion years out of an infinite time span is capable of supporting life, then any life observing the universe will be in that 100 billion years, not before or after."

This view posits a period (our own) somehow within an "on going" "eternity"--a kind of eternity sandwich ss it were where life forms occur only "between the 'slices' of eternity." Thus ee have the peculiar idea that an eternity "in progress" exhibits a bounded interlude--in which we necessarily can only exist--after which the eternity exits this interlude ("again") forever just as was the eternity which "preceeded" the special conditions required for life.

You're right: I do not buy that, either. But I lack the facility in math to present a neat formulaic proof supporting my scepticism.

By proximity1 (not verified) on 26 Jan 2016 #permalink

his view posits a period (our own) somehow within an “on going” “eternity”

Yes of course. Positing an infinite number of seconds does not eliminate any individual second or set of seconds. Why would it?

Honestly I don't think my idea is peculiar. I think your negation of it is. How do you get from "boundless time" to 'therefore no discrete time periods of 13 billion years possible?' Are you next going to tell me that on an infinite flat plane, no two points can be a meter apart?

"How do you get from “boundless time” to ‘therefore no discrete time periods of 13 billion years possible?’ Are you next going to tell me that on an infinite flat plane, no two points can be a meter apart?"

I'm going to tell you that we don't exist within any space-time infinity. Ours is a finite existence always bounded in the four-vector of a single (and I suppose unique) universe event--within this I accept that our general physical sciences are basically true and professionally accurate. I don't disparage the "pedigrees" of SR, GR, QM, or even a basic big bang inflation. I take these as features of the typical cyclical universe events, unique only in their details of historical experience. But these scientific theories are of course neither complete nor error-free. That, too, is an observation, not a complaint. There are surely mistakes somewhere in their conceptual relationships since scientists are still in search of a unified theory.

Within finite existence--the only "kind" possible for a universe which is not a absolute vacuum, devoid of both matter/energy and any space-time fine structure--there of course exist discrete, severable parts of spacetime and physical matter. Your example of an infinite flat plane on which there are two points separated by a measurable length is a conceptual construct, perhaps capable of being modelled and used in mathematical abstractions, but beyond that, not a possible feature of physical reality. Infinity as I suppose it must be isn't divisible either spatially or temporally. It's an absolute concept and this absolute quality is its only "feature". It can have no physical components, no durations or locales, and so, yes, no two points a meter apart on an infinite plane--flat or otherwise.

By proximity1 (not verified) on 27 Jan 2016 #permalink

@ 53: "provisionally accurate" not "professionally" FFS!

53 replies to 52.

By proximity1 (not verified) on 27 Jan 2016 #permalink

I think the weak anthropic principle only states the obvious: we only exist in these or, in any generally, physical circumstances which were, prior to our present existence, compatible with its occurrence and, only for as long as this compatibility endures. So, yes, that presupposes your point that we can only observe universe conditions which are, a priori, compatible with our observing them.

I do not presume that something which they we'd classify as life necessarily arises in every universe event. It merely happened to in this case.

And, on topic, I don't think orthodox Jews, Christians and Muslims have compatible notions of God which could allow them to unite in the worship of a single, mutually accepted identity for their diety.

;^)

By proximity1 (not verified) on 27 Jan 2016 #permalink

@ 50: "No, there is no contradiction in the term ‘infinite distance.’ You just don’t like it. "

It's not that I "just don't like it." It's rather that using the term "infinite" to specify a particular instance of a "distance" does violence to the meaning of "infinite." I have nothing personal against either term. They're very nice when used reasonably.

@ 51: "If only ~100 billion years out of an infinite time span is capable of supporting life, then any life observing the universe will be in that 100 billion years, not before or after."

That true. But it does not grant us a license to decide, upon a whim, that our existence is only a part, a feature of an absolute condition we call "infinite" any more than we can assert that evidence proves that God exists but this evidence occurred--or later shall occur--outside the window of our existence "within" the eternity which was in progress before us and which obviously carries on after we're that "eternity's" "history."

By proximity1 (not verified) on 27 Jan 2016 #permalink

I’m going to tell you that we don’t exist within any space-time infinity....

...Within finite existence–the only “kind” possible for a universe which is not a absolute vacuum...

...Your example of an infinite flat plane on which there are two points separated by a measurable length is a conceptual construct, perhaps capable of being modelled and used in mathematical abstractions, but beyond that, not a possible feature of physical reality...

These are all your assertions, proximity, nothing more. Back them up with data or at least an argument. (On the last: I would agree this universe isn't an infinite flat plane, but I want you to back up your assertion that such a universe is not possible. How do you know this?)

And if you don't want to answer all three, focus on the second one, as its your biggest whopper. On what basis do you claim that an infinite universe with stuff in it is impossible?

It’s not that I “just don’t like it.” It’s rather that using the term “infinite” to specify a particular instance of a “distance” does violence to the meaning of “infinite.”

How? This again appears to be a mere assertion rather than some sort of backed-up fact or argument. Scientists use equations with infinites in them to describe real objects all the time. We calculate volume using an infinite number of infinitesimally thin sections. We calculate a QM probability using r from some value to infinity. We calculate the energy required to ionize an electron by assuming it must be moved an infinite distance away from the nucleus. Are we "doing violence" to the notion of distance in these cases? I'm frankly not even sure what that means.

@ 57:
,..." focus on the second one, as its your biggest whopper. On what basis do you claim that an infinite universe with stuff in it is impossible?"

I started from a consideration of the implications of GR. Namely that an object's location, velocity (or, conversely, rest state) and direction are, since the work of Planck, Einstein and others (if not indeed since certain pre-Socratic Greek philosophers), impossible to determine in an absolute manner. They can only be given a value which is based on their relative relation to another object's or objects' location, velocity and direction.

In finite spacetime this does not pose insurmountable problems because coordinates can be devised, reference frames can be agreed to and these can permit relative location, velocity and direction to be determined.

Infinity's defining characteristic is the absence of any frame or reference either temporally or spatially. Even an arbitrarily agreed frame of reference is impossible since there are no starting points from which to develop such a frame. The "distance" to any hypothesized object is always the same--infinite. But worse, without pre-existing frames of reference or coordinates, it is not even possible to detect the presence of velocity, directions "towards" another object. In your proposed example you take two points with a pre-determined finite distance between them as the initial "given" conditions. You're obliged to choose a separation distance which is obviously "within view" because if the two objects weren't, there'd be no way, in infinity, to determine a "direction"--any direction.
But how in the world are these to "objects" supposed to be "placed"? And, if they are supposedly "already 'there' ( where!? ) how could they possibly be "found" ( located ) "in" infinite space--unless, again, this is already a given feature of your contrived example?

You are trying to flippantly employ a cincept which is the essence of the absolute without care or regard for the implications of your assumptions.

If after this you still don't see my point, there's nothing more I can think of to clarify it further.

Your math examples of the "uses" of unfinity are all cases where the term us used figuratively to refer to an appriximation since in no calculation is infinity specified with exact precision. It's merely the point where the calculations reach the limit if their precision and meaningfulness.

By proximity1 (not verified) on 27 Jan 2016 #permalink

Indefinite expansion does not mean that distances between objects will ever actually reach infinity.

By Another Matt (not verified) on 27 Jan 2016 #permalink

I am guessing, because I find Proximity's arguments incoherent (perhaps the reason he doesn't want to go to "Starts With A Bang" is because he tried them there already), but maybe he is thinking of Zeno's Paradox, which I would state as: in order to move a distance L if space is continuous, a moving object must traverse to its end a sequence of points which has no end. Zeno concluded from this that motion is like a scene in a movie, composed of many individual frames that jump a finite distance. One could say that he anticipated quantum mechanics.

The points Zeno was referring to were of course L/2. 3L/4, 7L/8, and so on. 2000 years later, mathematicians had converted his problem of traversing an infinite number of points to summing an infinite series (L/2+L/4+L/8+...) and defined the sum as the limit (using the epsilon-delta process) of the sequence of partial sums. They concluded that we do not have to physically sum the series to prove that its sum is L.

This would not have surprised Zeno - he defined the distance as L. Without disparaging the usefulness of advanced calculus, I wonder if the mathematicians have really solved Zeno's Paradox. Is nature a mathematician, to use the epsilon-delta limit process, or does it actually have to physically add up an infinite series?

I posed this question at "Back Reaction" and got a (perhaps deservedly) dismissive answer: the math we use seems to predict nature, and that is all we need to know and perhaps all we can know. Still it would seem more understandable to me if space-time were quanitized into discrete lengths rather than continuous.

However, I see no such conceptual problem with an infinite, open-ended universe. To me that simply means that the end of that universe in space and time cannot be reached - which doesn't bother me. I never expected to reach it. I do expect to get from point A to point B in it, though, as long as |B-A| is not too large.

Meanwhile, it seems to me that although our physics math is continuous, a discrete math with small enough intervals would approximate it for most purposes (as differential equations can be approximated by finite-difference equations) and in fact all our calculations use a finite number of digits. (I started my engineering career using a slide rule, but I could only read a few digits off it.)

@ 60: ..."maybe he is thinking of Zeno’s Paradox, "...

Not at all. Sorry you wrote so much. If there'd been anything to do with Zeno's paradox in my point l'd have mentioned it by now.

At this point I'd be more interested in the points raised by Jason's OP than what we've digressed to take up.

No common God from these three religions' sacred texts. But s humane God might be derived from them and agreed to for common worship--if these faiths had enough humanitarians among their faithful.

By proximity1 (not verified) on 27 Jan 2016 #permalink

@ 60: ..."I find Proximity’s arguments incoherent"....

Well then I find that reassuring.

By proximity1 (not verified) on 27 Jan 2016 #permalink

RE: Another Matt

January 27, 2016
Indefinite expansion does not mean that distances between objects will ever actually reach infinity."

The whole point I have tried to make is that infinity, being absolute, cannot be attained, or "reached,"--ever.

By proximity1 (not verified) on 27 Jan 2016 #permalink

Infinity’s defining characteristic is the absence of any frame or reference either temporally or spatially. Even an arbitrarily agreed frame of reference is impossible since there are no starting points from which to develop such a frame.

This is completely untrue. The starting point is arbitrary, but we can pick pretty much any point we want. If I have an infinite plane, I pick a point. Then I measure distance or coordinates in relation to that point. Its trivially easy, not "impossible" at all.

The “distance” to any hypothesized object is always the same–infinite.

This gets back to what I said before; you seem to be claiming that on an infinite plane, no two points could be exactly 1 meter apart. This is clearly false. It is simply not geometrically true that all points in an infinite plane or space are infinitely far apart from each other.

Your math examples of the “uses” of unfinity are all cases where the term us used figuratively to refer to an appriximation since in no calculation is infinity specified with exact precision. It’s merely the point where the calculations reach the limit if their precision and meaningfulness.

Maybe Jason or another mathematician would like to weigh in here, but I believe you have it exactly backwards. Integral calculus provide exact, analytic solutions to (some) problems containing infinities. When we use finite sequences of terms, we are approximating the true answers that are given by integral calculus.

The whole point I have tried to make is that infinity, being absolute, cannot be attained, or “reached,”–ever.

I have not been saying that a universe that starts out with a finite volume and expands continuously will, at some time t, reach infinite volume. If that's what you think I'm claiming, sorry, we have been talking past each other. What I am saying is (1) you have not actually given any argument against the notion that the universe could continue to expand without stop, (2) your notion that matter density has something to do with lambda is completely unfounded, and (3) you are also wrong about it being impossible to measure distances between objects in hypothetical infinite spaces. We can of course posit points infinitely far away from each other in such a space, but there is no argument of logic or geometry that requires all pairs of points to be in that category - which is what you are claiming.

It's almost 30 years ago that I studied projective geometry, so it took me a few minutes to remember correctly that you can specify infinity in a two-dimensional space by using three coordinates.

https://en.wikipedia.org/wiki/Homogeneous_coordinates

Again if my memory serves me well this is used when firing cannons.

There's also this, which allows you to use infinity sensibly in algebra (and I think one of the only ways that you are allowed to define infinity as 1/0, at the expense of forgoing positive and negative infinities as limits). I'm not a mathematician, though!

https://en.wikipedia.org/wiki/Projectively_extended_real_line

By Another Matt (not verified) on 27 Jan 2016 #permalink

@64:
..."lf I have an infinite plane, I pick a point."...

But my point is--and has been--that all you've done here is posit a condition as an a priori given. You assume the infinite plane. That's sort if OK "on paper, " as a thought experiment or for use in an abstract model-- provided that these are taken to be features of physical reality.

Again : infinity is a theoretical I have not been saying that a universe that starts out with a finite volume and expands continuously will, at some time t, reach infinite volume. If that’s what you think I’m claiming, sorry, we have been talking past each other. -like God-it doesn't exist in physical reality.

So " if [you] have an infinite plane" then, PLEASE, show it to us
I've never seen one--ever.

Meanwhile, I'm going to revisit Steve Martin's comedy routine, "YOU can be a Millionaire!"

Please note comment 59 RE:
..." talking past each other"....
Not, at any rate, concerning _that_ remark. Elsewhere, it may be tbe case I fact.

By proximity1 (not verified) on 27 Jan 2016 #permalink

@ 68: corrrection:

..." provided that these are NOT taken to be features of physical reality."...

Jesus F'ing Christ!

By proximity1 (not verified) on 27 Jan 2016 #permalink

@ 65 :

From your Wikipedia Link;

"In geometry, a point at infinity or ideal point is AN IDEALIZED limiting point at the "end" of each line"

(Emphasis (and capitalisation) added.)

By proximity1 (not verified) on 27 Jan 2016 #permalink

But my point is–and has been–that all you’ve done here is posit a condition as an a priori given. You assume the infinite plane.

For the most part I'm responding to your claims, which would appear to apply to hypothetical infinite spaces. I will give you an paragraph example:

Infinity’s defining characteristic is the absence of any frame or reference either temporally or spatially. Even an arbitrarily agreed frame of reference is impossible since there are no starting points from which to develop such a frame. The “distance” to any hypothesized object is always the same–infinite. But worse, without pre-existing frames of reference or coordinates, it is not even possible to detect the presence of velocity, directions “towards” another object.

That's several arguments YOU are making about infinite spaces, and in responding to them, I'm pointing out that your arguments about infinite spaces are wrong. We can develop relative frames of reference for hypothetical infinite spaces. Arbitrary frames of reference are not impossible, and the distance between any two points is not necessarily infinite. And it is certainly possible for objects near each other in this space to detect the presence of velocity etc...

Now, if you want to claim that you're not discussing the properties of (hypothetical) infinite spaces, please tell me what that paragraph you wrote was supposed to mean.

This entire discussion started with your claim in @34 that limitless expansion is an impossibility. To back that claim up, you've made additional assertions about the nature of infinite spaces. As far as I can tell, your overarching argument is that because infinite spaces are a logical impossibility, no physical process could produce it. Endless expansion would produce one, therefore endless expansion is a logical impossibility. Right now, I think every single claim in that argument is wrong. Infinite spaces are not logically impossible because you arguments backing them up don't hold together (that's where my analysis of your paragraph, above, comes in). Endless expansion never produces an infinite universe at some defined time t, it just means that at t+1 the universe will be larger than it was at time t, for any t. And because premises 1 and 2 fail, your conclusion (that endless expansion is logically impossible) is not valid.

Now, maybe I've gotten your overarching argument wrong. If so, please correct me. But that's how I see it.

@ 71:

Compare your,
..."This entire discussion started with your claim in @34 that limitless expansion is an impossibility"...
(emphasis added here above and following below)
with my post,

..." Personally, I think the infinite expansion of the Universe is a logical impossibility–as I do with all things “infinite” except, notably, a special case: in the realm of mathematics, which is an abstract art, a theoretical philosophy, not a natural science, there are “infinte series,”–it’s a manner of speaking, a theoretical construct, and not something either real or even realistic. Only in theory are numners infinite–...."

These are not the same ideas--though I understand your confusion and may have unintentionally contributed to it. I can and do agree that a finite universe might expand "without limit"--but not "infinitely" and I didn't make the distinction clear (it didn't occur to me to explain that unlimited expansion is not even on the far "outer reaches" of infinity--that's a joke! Infinity cannot have "outer reaches"!); I dispute the idea that the expansion could become or could equal infinity or infinite space. There would arrive a point at which the universe's space would lose any coherence--that is, I suppose, at a state far beyond its "heat death." I mean a state in which every particle is suspended in isolation from any other by distances which are inconceivably greater than the universe at a hypothesised near-heat death stage of expansion. Many billions of trillions of times larger than that stage would not even approach this magnitude. BUT it would still be a "magnitude", still be finite in extent"As far as I can tell, your overarching
argument is that because infinite spaces are a logical impossibility, no physical process could produce it."...

No, that is not my argument. I'm arguing only that no physical space containing matter/energy (such as our univserse) can be infinite and would constitute, yes, a logical impossibilty.

... "Endless expansion would produce one, therefore endless expansion is a logical impossibility. "

To conclude, I contend that such an endless expansion of a universe of matter/energy would not be infinite. It would be of a magnitude difficult to conceive but note!: as it would continually expand, it neither could nor would be, on that account, infinite--since the infinite cannot "expand."

By proximity1 (not verified) on 28 Jan 2016 #permalink

I think I can finally piece together some proximity1's arguments. I've probably got some details wrong, but I think it goes like this:

1. In relativity, adopting a frame of reference depends on there being nearby matter or energy to refer to. In order for space to be infinite in extent, there needs to be an infinite amount of stuff to refer to.

2. There is a finite amount of mass and energy.

3. If time extends infinitely into the future, the universe is continually expanding, and heat death involves proton decay, then since there is a finite amount of stuff, the distance between particles will tend toward infinity with time.

4. As time and distance between particles tend toward infinity, the ability to adopt a frame of reference disappears, leaving us effectively with no space and no time at all, or gazillions of single-particle island universes.

5. Therefore, in order for the universe to continually be a universe, time (and possibly space) must be bounded and/or cyclical.

By Another Matt (not verified) on 28 Jan 2016 #permalink

@ 73:
That's not a bad statement of much of what I thought I'd already tried to say. I'm just flabbergasted that your comment seems to imply that it took a great deal of time and effort to grasp all of that.

By the way, not just "In Relativity...". A frame of reference is essential under any cosmological order's basic structure and physics.

I'll add this further distinction between infinity and its incredibly distant nearest "neighbour, " the continually-expanding finite universe: in the latter, there can be movement--as your summary notes--while infinity presents no such possibility. First, there are no refernce points and no way to distinguish between motion and rest. Second, after eons of supposed movement, the figurative particle would be neither closer nor farther from anything else--supposing, that is, that there is anything else.

Good summary from you. I'm sorry it cost such an effort.

By proximity1 (not verified) on 28 Jan 2016 #permalink

@ 73: ..."time (and possibly space) ...

Both, of course. If the universe isn't empty, then time and space are mutually dependent, mutually contingent aspects.

By proximity1 (not verified) on 28 Jan 2016 #permalink

I can and do agree that a finite universe might expand “without limit”–but not “infinitely”

Okay, then we may be getting closer. I think that the lambdaCDM and similar theories predict that the universe will expand indefinitely, which may be subtly different from infinitely. IOW, there is nothing we know of, at present, which would cause the current expansion to stop.

I agree that this expansion predicts that at some far future point, every particle may essentially be it's own 'island universe.' I'd also agree that to a particle in that state, there can be no observable difference between "I'm causally isolated from anything else" and "I'm causally isolated, and the isolation is growing." There would be no way to assess or evaluate whether the isolation is growing or not in that case. Is that what you are saying?

Note however that such a particle could re-establish a local frame of reference with other particles or with the structures produced via quantum fluctuations around it, if/when the expansion slows down. This is what happened at the end of the inflationary epoch; the expansion of space went from 'faster than the speed of light between any two particles, even those separated by femtometers' to 'its only faster than the speed of light for things separated by billions of lightyears.'

I dispute the idea that the expansion could become or could equal infinity or infinite space. There would arrive a point at which the universe’s space would lose any coherence

Ah. Well as to the first sentence, as I said above I don't think anyone is claiming that the universe will reach infinite extent in some finite time t. That is a subtly different claim from "expanding forever," and while AFAIK some cosmologists make the latter claim, again AFAIK nobody makes the former claim. If the former is what you're attacking, be aware that you may be setting up a straw man. To your second point I would say, "so what?" It may be true that internally to these particle-universes, the notion of further expansion makes no sense. But we can still meaningfully discuss whether expansion is occurring to an ensemble of such particle-universes, as we do when we discuss inflation, because the time and rate of inflationary expansion after we reach the island-state results in quantitative predictions about what the universe should look like today. It is meaningful, for instance, to say that at time t particle A became causally isolated, but that the expansion continued until t+4 and grew exponentially faster during those four increments. Particle A would have no way of measuring or evaluating those claims, but once the inflationary period stops, what A sees around it can be used to back-calculate these parameters it had no access to during inflation.

Does that make sense? Is there anything there you disagree with?

Not that it matters what I think, but I think I disagree with all of Another Matt's 5 points (which he may or may not agree with himself).

1. A reference frame was originally defined with respect to "an observer", but the observer was usually hypothetical, used in a thought experiment. The universe doesn't care whether or not there are observers. More generally, a reference frame can apply to any sort of interaction - even those among virtual particles - which the universe may never run out of.

2. Energy is not conserved under General Relativity, so more is always available in an expanding universe.

3. Not necessarily true due to 2, and if so, so what?

4. Not necessarily true, due to 1 and 2, and if true so what?

5. The argument of 3-5 seems to be: if this (expansion) goes on, I don't like what will result, so I'll stop calling it a universe at some point (and where is that point exactly - how large must the mean free path be between particles? When does the universe become a non-universe?). The universe doesn't care what we like or don''t like, and will not stop expanding on our account.

Proximity @74:

First, there are no refernce [sic] points and no way to distinguish between motion and rest. Second, after eons of supposed movement, the figurative particle would be neither closer nor farther from anything else–supposing, that is, that there is anything else.

I think you are again confusing an infinite island universe containing only one particle, and a "plain old" infinite universe that contains many. They are not the same concept. Your statements above might be true of a universe containing one particle, but is not generally true for all possible infinite universes.

Incidentally, a continuously expanding universe does not imply that everything eventually becomes causally separated. All four known physics forces are stronger than the expansion at short distances. For example, the current rate of expansion will never - not even given infinite time - pull the solar system apart (gravity). Or pull molecules apart (electromagnetism), or pull atoms apart (strong and weak forces). The force it exerts at these distances is far weaker than the other forces holding them together. For the island universe scenario to happen, there needs to be some additional factor. Another inflationary epoch, the decay of what's currently considered to be stable matter, or maybe the assumption that everything merges into black holes which then decay. Without some additional assumption like that, what indefinite expansion produces is merely cold matter, collected in gravitationally held together clumps, separated by ever-expanding distances.

Also, Boltzmann statistics says that it is possible for random fluctuations to produce hot spots and cold spots in any set of particles - unlikely, but possible, and the bigger the universe the bigger the possibility. In an infinite universe (which will never be reached), the probability of a warm galaxy somewhere is might be very close to 1.

As for proton decay, it wouldn't cause the component quarks to disappear. What decays can recombine, as with neutrons.

I don't think anyone is an expert here, which is why I suggested raising the issue at "Starts With A Bang". I don't claim I know what is going to happen to the universe, but I would need a lot better data and arguments than I've seen here to convince me that someone else (who disagrees with the consensus of physicists I've read) does.

As for proton decay, it wouldn’t cause the component quarks to disappear.

Indeed. And the fun thing about quarks is when you pull them apart, the work of pulling them apart produces more quarks. :)

blockquote>
" But we can still meaningfully discuss whether expansion is occurring to an ensemble of such particle-universes, as we do when we discuss inflation, because the time and rate of inflationary expansion after we reach the island-state results in quantitative predictions about what the universe should look like today. It is meaningful, for instance, to say that at time t particle A became causally isolated, but that the expansion continued until t+4 and grew exponentially faster during those four increments. Particle A would have no way of measuring or evaluating those claims, but once the inflationary period stops, what A sees around it can be used to back-calculate these parameters it had no access to during inflation.

"Does that make sense? Is there anything there you disagree with?"

Not as long as we're confining ourselves to a parlour game, no. All of that would be fine. But I don't think it has any useful interest for us as a practical picture. It seems to me that Particle A, in such an isolation, would find itself also equally
isolated from all energy (and, who knows?, any gravitational field influence)--this would imply a total darkness since the "nearest" photon, like Particle A, would be in the same state of isolation. I can't imagine who or what could conceivably do this "back-calculation" in such conditions. But, again, as a parlour game, it has a certain charm.

"I think you are again confusing an infinite island universe containing only one particle, and a “plain old” infinite universe that contains many. They are not the same concept. Your statements above might be true of a universe containing one particle, but is not generally true for all possible infinite universes."

I have already stated more than once here that I don't contend any such possibility of an infinite universe containing matter/energy--whether it is one single particle or any larger number of them. Nor have I claimed that "a “plain old” infinite universe that contains many" and this former "are ... the same concept." Maybe you're misinterpreting something above? Or have I not understood your point here?

"Incidentally, a continuously expanding universe does not imply that everything eventually becomes causally separated. All four known physics forces are stronger than the expansion at short distances." ...

Does the scenario I suggested concern anything that could be classified as "short distances"? Though not infinite, the distances would be so large that, to calculate them would require more time than what I imagine a universe-event to present--again, assuming, impossibly, that there'd be anything or anyone to do the calculation.

..." For example, the current rate of expansion will never – not even given infinite time – pull the solar system apart (gravity).

Speaking of bold claims, there's one. I wonder how you can reasonably support the use of "never" there. Doesn't current and very ordinary cosmology take it for granted that this, our solar system--like any other--has a sun with a finite lifespan? And doesn't it presume that the Sun's energy will, barring other intervening events which might shorten the Sun's natural lifespan, burn out, and produce one of the late star forms? At that point, what and where is the source of the gravity that would hold this then-dead Sun's solar system "together"? If there is none, why, then would its former constituents not be subject to all manner of drift, collision, and other course-changing influences? In short, why would former orbits persist without the Sun's presence as we know it?

How about, for example, the heat-death of the Universe? --which would presuppose, I gather, the final eventual extinction of all stars--and with them, their gravitational influences? Could that do it?

If you say that other stars are always in formation I answer by asking that, while this is the case today, what basis have we for supposing that, as you put it, "even given infinite time" it would remain just as it is today? If the universe is in this much-cherished accelerated expansion ( which I question for its interpretive accuracy) then how are you able to maintain such certainty that later the forces we regard as sufficient to keep things together shall not be overcome by increasing acceleration of expansion?

..." the decay of what’s currently considered to be stable matter, or maybe the assumption that everything merges into black holes which then decay. Without some additional assumption like that, what indefinite expansion produces is merely cold matter, collected in gravitationally held together clumps, "

What is the source of this gravity under the conditions you describe here?

And, even if we grant this picture, these "clumps" --some very large, of course, would themselves be ultimately so isolated in spacetime that, again, the time required to even state descriptively the "nearest location" would be greater than a universe-event. Again, no one and nothing to do the calculations at this point. .

Note RE: the citation with the "(sic)" :
First, there are no refernce [sic] points ---

If you'll agree not to nit-pick my (frequent) typographical errors, in return, I'll agree not to tax you with a recitation of how terribly tedious and frustrating it is for me to have to read, and compose replies using the bullshit technology of a hand-held device at my disposal.

This was composed on a desktop computer but the availability of these is, for me, very limited. Most of the time, I'd squinting to read a tiny screen and trying to type on a maddeningly difficult little key-patter on that tiny screen.

By proximity1 (not verified) on 28 Jan 2016 #permalink

@ 79:
..."I would need a lot better data and arguments than I’ve seen here to convince me that someone else (who disagrees with the consensus of physicists I’ve read) does."

Good idea! Go and consult the experts on the consensus of physicists. They'll tell you about their data--lots of it-- and their arguments--lots of them.

https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics#Unso…

Quantum physics:
https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics#Gene…

Cosmology and General Relativity (GR):
https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics#Cosm…

Quantum gravity:
https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics#Quan…

High energy/particle physics:
https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics#High…

Astronomy and astrophysics:
https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics#Astr…

By proximity1 (not verified) on 29 Jan 2016 #permalink

It seems to me that Particle A, in such an isolation, would find itself also equally isolated from all energy

Well the particle itself is a manifestation of energy. And according to Heisenberg, there is no such thing as a defined space of exactly zero energy. delX*delP>=hbar/2. So that scenario is just impossible unless you know something about physics the rest of us don't.

I can’t imagine who or what could conceivably do this “back-calculation” in such conditions. But, again, as a parlour game, it has a certain charm.

We have done it. We live in a universe that was at one time in a state where every particle was in causal isolation, then inflation slowed down, and we are able to use the observed characteristics of the universe to back-calculate how long the inflationary period lasted. So it's not a parlour game at all. My claim that this can be done in principle is based on the empirical observation that humans have done it.

have already stated more than once here that I don’t contend any such possibility of an infinite universe containing matter/energy

Yes I know. You keep asserting that an infinite universe can't have collections of matter or energy in it. But you just keep repeating this assertion, you never tell us why this is so.

…” For example, the current rate of expansion will never – not even given infinite time – pull the solar system apart (gravity).

Speaking of bold claims, there’s one. I wonder how you can reasonably support the use of “never” there.

Empirical observation. The expansion is about 75 km/sec/Mpc. Neptune is about 4.5E9 km from the sun, or about 1.46E-10 Mpcs. Which means its expansion is about 1 E-8km/sec, or 0.01mm/sec. During Neptune's yearly orbit around the sun, it will naturally and stably vary in its orbit by 10 billion km. To be clear: the gravitational force holding it in orbit around the sun is strong enough to continue to hold Neptune in place against annual orbital changes of this size. In contrast, the expansion "pushes" Neputune away from the sun by about 52 km per year. Which is 12 orders of magnitude too weak to make any difference. So the current rate of expansion will never move Neptune away from the sun, because the gravitational attraction pulling it in overwhelms the 'force' of the expansion of space pulling it out. Other factors can change Neptune's orbit, of course. Some fly-by planet, or when our sun eventually goes nova. And if the expansion increased, all bets are off. But if it stays constant, this particular effect will never pull the solar system apart. Now of course our solar system will die before that happens. What is important to understand for your point is this: when, in some far future where suns have burned out and all we have is cold dark matter, that cold dark matter will not be pulled apart into constituent subatomic particles by the universal expansion either. Because gravity, electromagnetics, weak and strong forces can all hold clumps of that matter together better than the expansion can pull them apart.

(For the other physical forces, the situation is many orders of magnitude more in favor of the force over the expansion, because the distances on which they operate are about 18 orders of magnitude shorter and the forces themselves are about 40-45 orders of magnitude stronger. Molecules and nuclei are in much better shape than solar systems, which are already in good enough shape to resist the expansion.)

And, even if we grant this picture, these “clumps” –some very large, of course, would themselves be ultimately so isolated in spacetime

My point in bringing up clumps of cold dark matter was to point out that you are wrong about the impossibility of having a frame of reference or detection of velocity, etc. in such a space. A clump allows me to say atom A of the clump is at x,y,z, while atom B of the clump is at x+1, y-1,z+10 in the clump. I can also observe that B is rotating around A, or that one has an internal spin compared to the other, etc...

So, in summary, you're wrong in your @41 claim that continuous expansion will result in causal isolation for every individual particle. That could happen, if the expansion rate changed. Its certainly a possibility, since we know the expansion rate was higher in the past. It could also happen if dynamic interactions in those clumps blow things apart sufficiently far away. But the current expansion rate could operate for infinite future time and your everything-pulls-apart scenario is still not inevitable, not demanded by physics. A clump of matter in equilibrium would stay a clump of matter for the entire infinite future history of such a universe.

And you're also wrong about not being able to have a frame of reference in such a scenario. With clumping comes the ability to make relative measures of properties.

Lastly, I have to say that none of your assertions even speak to the question of why the fate you predict is logically impossible. If we assume that you're right and that eternal expansion would lead to single-particle island universes...so what? Why is that end-state logically impossible?

Opinions on the shape (and future) of the universe differ. Here was Lord Bryon's (from a blog post by Dr. Sean Carroll, the cosmologist).

Darkness, by Lord Byron:

I had a dream, which was not all a dream.
The bright sun was extinguish’d, and the stars
Did wander darkling in the eternal space,
Rayless, and pathless, and the icy earth
Swung blind and blackening in the moonless air;

... yada, yada, yada, ...

The waves were dead; the tides were in their grave,
The moon their mistress had expir’d before;
The winds were withered in the stagnant air,
And the clouds perish’d; Darkness had no need
Of aid from them – She was the Universe.

Dr. Carroll's comment on the poem:

"It would appear, then, that Byron is predicting that dark energy will continue to dominate in the future, resulting in the ultimate heat death of the universe; no phase transition to a true vacuum, nor a Big Rip. He doesn’t mention the possibility that quantum fluctuations will produce new baby universes in the future, but perhaps that was another poem."

Heat death, as I understand it, is a macroscopic average, like the temperature (average energy) of a volume of gas. Within the volume there can be a distribution, and the bigger the volume the longer the tails of that distribution. (Even the Darkness might contain tiny flashes of light.)

@83: well given enough time all macroscopic objects would reach equilibrium and the only distribution you'd see would be what arises from quantum fluctuations. But to riff on Carroll riffing on Byron, it appears proximity is claiming a big rip is impossible because infinities can't happen, and therefore any model that predicts big rips must be wrong. IMO a big rip is certainly possible, though not inevitable, and whether we expect that the universe will undergo one or not will be answered by empirical measurement of things like the expansion rate, not by philosophizing on the nature of infinity.

***

One follow-up to my @82 comment: Proximity, one example which may help you think about my bold claim is to think about what happens when you take two powerful, light magnets connected to each other, and hold them vertically so one "hangs" under the other. If such a situation could be made stable forever, would the Earth's gravity alone ever pull them apart? Does the amount of time this situation goes on matter for the answer? Answer: no, and no. Something must perturb the system (the magnets decay; your hand gets tired, gravity increases) to make them separate. Similarly with the expansion vs. solar systems, molecules, and nuclei. The current expansion rate could go on forever and unless those systems are perturbed in some other way, they will never be pulled apart. The current expansion rate alone can't do it, just as the Earth's gravity would never 'eventually' pull two strong light magnets apart.

"Well given enough time all macroscopic objects would reach equilibrium and the only distribution you’d see would be what arises from quantum fluctuations."

Maybe that's true, but off-hand I can't think of a mathematical proof of it. It is not clear to me that in an almost infinite space there can't be a hot spot the size of a galaxy without having a significant effect on the overall average and variance of the temperature. That is, the average and variance could still be very close to zero. E.g., the "vacuum" of space is very cold despite having high-energy "cosmic rays" shooting through it.

"IMO a big rip is certainly possible, though not inevitable, and whether we expect that the universe will undergo one or not will be answered by empirical measurement of things like the expansion rate, not by philosophizing on the nature of infinity."

True (and that applies to all of my speculations as well), and especially true when it comes to Berkeleyian arguments which seem to suggest that the universe should care whether we would consider it a universe or not.

@ 86: ..."and especially true when it comes to Berkeleyian arguments which seem to suggest that the universe should care whether we would consider it a universe or not."

Yes, "especially true when it comes to those. Never mind the fact that no one here has suggested anywhere in the course of the above anything even remotely like that. So the comment is, if not insulting, at the very least, gratuitous.

By proximity1 (not verified) on 29 Jan 2016 #permalink

"... As time and distance between particles tend toward infinity, the ability to adopt a frame of reference disappears, leaving us effectively with no space and no time at all, or gazillions of single-particle island universes.

5. Therefore, in order for the universe to continually be a universe, time (and possibly space) must be bounded and/or cyclical."

That reads to me as "if the universe expands continually it will cease to be what I would call a universe, therefore it can't happen." Aside from the fact that I don't accept the assumptions, that argument sounds Berkeleyian/creationist to me - similar to those who say that the universe is all in our heads (and therefore subject to our wishes) or that the idea of a universe without a creator god blows their minds (and what blows their minds can't be real). Either of which could turn out to be correct, but neither of which seems to me to be to be any kind of logical necessity. I will agree that this reaction of mine could possibly a) be mistaken and b) have been stated less harshly - but it was my reaction.

Meanwhile, I have found what I think is a good reference on such speculations, by an expert:

http://www.preposterousuniverse.com/blog/2013/08/22/the-higgs-boson-vs-…

In their paper (cited) Bunn & Hogg are flatly opposed to the stretching of space as a reasonable account of the supposed general acceleration (at an extreme scale) of the far distant visible universe. They dispute the interpretion, not the data behind it. For them, this is in no way the settled issue that it is presented to be here. I find myself in a quandry because their views strike me as eminently sound but not because I can follow their mathematical grounds--for I cannot. I'm unable to explain clearly or easily why their exposition convinces me; but it does and I experience a visceral sensation of the conviction that they are making good sense. It is if course an intuitive grasp of their case. If, for the sake of argument, there were errors in the formulae or equations they present in support, I wouldn't be able to spot them. How very much I'd like to have such an understanding of the mathematics central to this matter! How very much I'd welcome a clear explanation of the meaning and import of these formulae and equations so that I could spot mistaken formulations in them and so that I could state, as they do, why their interpretations and criticisms are valid. But, as far as I am able to
understand, they have done all that and, in all the foregoing comments, their arguments remain unanswered.

Since any interested reader here could refer directly to their text, it seems pointless to me to cite portions of it here in the hope of convincing those who disagree.

By proximity1 (not verified) on 01 Feb 2016 #permalink

I’m unable to explain clearly or easily why their exposition convinces me; but it does and I experience a visceral sensation of the conviction that they are making good sense.

This is called the "argument from incredulity," and it is a logical fallacy. So right off the bat, you've got a problem; the reason you cite for accepting the theory is a sign of bias, not clear or rational thinking.

I am by no means a cosmologist, but their paper seems quite cranky to me. Its very unusual in a scientific publication for the author to complain that "purists" won't listen to them or are going to interpret terms differently (than the authors). It's also really weird that they include a little fake vignette about being pulled over by a cop for speeding. That is really not how scientists typically write papers. On content: I think one major problem that would have to be addressed in their theory (that the redshift is normal kinematic movement, not space stretching) is that their hypothesis now needs to explain why the Earth is at the center of the universe. The standard model does not require our solar to be in a privileged position, but AIUI their kinematic model does, because it implies the red shifting we see is because everything in the universe really does have a velocity vector pointing more or less straight away from the Earth. A second scientific complaint would be that if they're right, there should be no limit to the observable universe because there can be nothing kinematically moving away from us faster than the speed of light. Thus their theory does not address Olber's paradox, while the mainstream theory does.

I missed some previous comments, which probably came in as I was making one of mine. #82 reinforces my creationist analogy, being a great example of a "Gish Gallup".

As for Bun & Hogg, Bun explains their position in layman terms here:

https://blog.richmond.edu/physicsbunn/2010/04/08/more-on-the-cosmologic…

"So I’d rather you not think of the Big Bang as an explosion “at a certain position in space”. It’s still true that it happened everywhere rather than somewhere. There’s no preexisting space into which stuff expands. For instance, if we imagine a closed Universe (i.e., one that has a finite volume today), its volume was smaller in the past, approaching zero as you get closer to the Big Bang. So in that sense space really is expanding."

"As Hogg says, the main thing we object to is the idea that the rubber sheet has its own dynamics and interacts with the stuff in the Universe — that is, that the stretching of the rubber sheet tends to pull things apart, or that it “stretches” the wavelengths of light. As far as I’m concerned, the main reason for objecting to this language is not because it gives the wrong idea about cosmology, but because it gives the wrong idea about relativity. The most important point about relativity is that space doesn’t have any such powers and abilities. If you’re a small particle whizzing through space, at every moment space looks to you just like ordinary, gravity-free, non-expanding space.

So if you’re going to abandon the heresy of the rubber sheet, what should you replace it with? I don’t have anything as catchy as the rubber sheet, unfortunately. What I visualize when I visualize the expanding Universe is just a bunch of small neighborhoods, each one of which is completely ordinary gravity-free space, but each of which is moving away from its neighbors."

In other words, their paper objects to the "rubber-sheet" analogy of expansion, but they agree that space is expanding.

Erratum: Bun should be Bunn.

@91 - well, that's definitely better than what I got from the paper. But I fear it doesn't leave proximity with much to object to.

If by "to object to" you mean "further basis to argue against expansion of the universe" there's always the young-Earth creationist proposal that the speed of light has varied.

I noted also that in the above blog post Dr. Bunn also says that Sean Carroll (whom I linked to earlier) "is not wrong", i.e. that they are in agreement about what General Relativity predicts about the evolution of the universe.

My take-away from the B&H argument is that the Hubble red-shift is caused by (and can be calculated by) a relativistic Doppler effect, not by photons being physically stretched by the expansion of space. The relativistic Doppler effect itself, however, is due to observers moving away from the source of the photons due to the expansion of space.

@ 91: thanks for the link.

@ 92:

From what I understand, your acceptances are based on a grasp of the formulae and equations which is very much like mine.

'This is called the “argument from incredulity,” and it is a logical fallacy. So right off the bat, you’ve got a problem; the reason you cite for accepting the theory is a sign of bias, not clear or rational thinking.'

Except for the fact that I'm agreeing with Bunn and Hogg --who I don't think you understand as well as I believe I do.

"I am by no means a cosmologist, but their paper seems quite cranky to me."

This latter looks very much like your
"Argument from incredulity."

I think you both miss their point. It's a pity we probably can't ask them to weigh in on this.

By proximity1 (not verified) on 01 Feb 2016 #permalink

No, it's not the same because I identified two different empirical ways in which their paper differed from standard mainstream papers. You, OTOH, talked specifically about gut feelings.

Be that as it may, they did weigh in: see JimV's correction of my position. So now that we both know they accept an expanding space, do you still accept their position?

On content: I think one major problem that would have to be addressed in their theory (that the redshift is normal kinematic movement, not space stretching) is that their hypothesis now needs to explain why the Earth is at the center of the universe. The standard model does not require our solar to be in a privileged position, but AIUI their kinematic model does, because it implies the red shifting we see is because everything in the universe really does have a velocity vector pointing more or less straight away from the Earth.

I don't have time to read the B&H article, but this comment reminded me of something that has been exciting a lot of creationists lately. Have you heard of redshift quantization? The idea is that the data we have indicate either that the redshift we see is organized in concentric, quantized shells about the earth, or that the matter in the universe is organized in these shells. The implication is supposed to be that the big bang is false, and that the earth really is the center of the universe as the Bible "predicts."

See for instance here:
http://creation.com/our-galaxy-is-the-centre-of-the-universe-quantized-…

And a comprehensive serial format refutation (oldest are last):
http://dealingwithcreationisminastronomy.blogspot.com/search/label/reds…

By Another Matt (not verified) on 01 Feb 2016 #permalink

I think I have an analogy which B&H would like, to replace the stretching-rubber analogy. Consider a 1-D space consisting of 5 space-units, numbered 1-5, represented by equals signs:

=====
12345

Now suppose they move one space-unit apart from each other, with new space-units a-d filling the gaps:

=========
1a2b3c4d5

An observer in 1 sees that an observer in 2 has moved away at a velocity of 1 (space unit per unit time), 3 at 2, 4 at 3 and 5 at 4. An observer at 3 sees that 1 has moved away at -2 velocity, 2 at -1, 4 at 1, and 5 at 2 (just like Hubble expansion). But the space-units themselves have not stretched - new space has been added.

That is how I think B&H see the universe's expansion - that space itself has not expanded, but the amount of space has expanded - a subtle difference. In any case, the universe is expanding.

I admit that I didn't quite understand the point that Bunn and Hogg were making, but since they mentioned Sean Carroll, I wondered if he had a comment on their paper in more comprehensible terms, and found this:

  • http://www.preposterousuniverse.com/blog/2008/10/06/does-space-expand/

I think the final two paragraphs are the takeaway:

On the other hand, there is another pernicious mistake that people tend to make: the tendency, quite understandable in Newtonian mechanics, to talk about the relative speed between two far-away objects. Subtracting vectors at distinct points, if you like. In general relativity, you just can’t do that. And realizing that you just can’t do that helps avoid confusions along the lines of “Don’t sufficiently distant galaxies travel faster than light?” And reifying a distinction between the Doppler shift and the cosmological redshift is a good first step toward appreciating that you can’t compare the velocities of two objects that are far away from each other.

The point is, arguments about analogies (and, by extension, the proper words in which to translate some well-accepted scientific phenomenon) are not “right” or “wrong.” The analogies are simply “useful” or “useless,” “helpful” or “misleading.” And which of these categories they fall into may depend on the context. Personally, I think “expanding space” is an extremely useful concept. My universe will keep expanding.

By Owlmirror (not verified) on 01 Feb 2016 #permalink

Or, as I think JimV is saying above, Bunn & Hogg don't seem to have any problem agreeing with Carroll (and other cosmologists) about the science, and what they disagree about is just the proper terminology to describe the cosmological phenomena.

Which is what I took away from the paper itself, but wasn't certain about.

By Owlmirror (not verified) on 01 Feb 2016 #permalink

As Hogg says, the main thing we object to is the idea that the rubber sheet has its own dynamics and interacts with the stuff in the Universe — that is, that the stretching of the rubber sheet tends to pull things apart, or that it “stretches” the wavelengths of light. As far as I’m concerned, the main reason for objecting to this language is not because it gives the wrong idea about cosmology, but because it gives the wrong idea about relativity.

The most important point about relativity is that space doesn’t have any such powers and abilities. If you’re a small particle whizzing through space, at every moment space looks to you just like ordinary, gravity-free, non-expanding space.

So if you’re going to abandon the heresy of the rubber sheet, what should you replace it with? I don’t have anything as catchy as the rubber sheet, unfortunately. What I visualize when I visualize the expanding Universe is just a bunch of small neighborhoods, each one of which is completely ordinary gravity-free space, but each of which is moving away from its neighbors.

In this picture, the redshift is easy to understand. If a guy in one neighborhood tosses a ball to his neighbor, the speed of the ball as measured by the catcher will be less than the speed as measured by the thrower. That is, the two measure different energies for the ball, not because there’s some phenomenon taking energy away, but just because they’re in different reference frames. If the catcher then turns around and throws again to his neighbor, the same thing happens again, and so on. That’s all the redshift is. It’s not some mysterious “stretching.”

Eric. it is folly to label my preference for one set of expert scientific opinion regarding an as-yet OPEN QUESTION over any other set of expert scientific opinion on the same matter(s) as falling afoul of the argument from incredulity--which, as a principle, I respect as a valid logical objection in those cases where this error is actually committed. But, seriously, if you can't see the distinction there then further discussion with you on this is truly pointless.

Your view would effectively exclude all but those who are fully conversant with the technical mathematics and formulae's use without resort to the aid of everyday language to explain these aspects. That, to me, is ridiculous and it would shut down nearly all lay discussion of these kinds of issues. Really, if you cannot get this, then we're done on this topic and I won't respond further on it here.

To say that the fact that Bunn and Hogg accept a model of the universe as one in which there is, yes, a general increase in volume, does not, as you think, "leave me with little" to which to object. Their objections are right there in plain English. No particular expertise in math is required to grasp this. And, for that reason, I remain committed to the views already stated: I agree with them in their interpretations, those are at odds with a view expressed here as that of a Universe in which space "stretches"--what you call the "standard model" --or more precisely the A: Freidmann model.and its variants.

By proximity1 (not verified) on 02 Feb 2016 #permalink

the main reason for objecting to this language is ... it gives the wrong idea about relativity.

By proximity1 (not verified) on 02 Feb 2016 #permalink

@ 99 :

You offer precisely the excerpt I'd take as an example of where Carroll misrepresents Bunn and Hogg. In fact, there is no place for Carroll to have written, "On the other hand when what follows it does not present any departure from Bunn and Hogg.

They, too, oppose "pernicious mistake that people tend to make: the tendency, quite understandable in Newtonian mechanics, to talk about the relative speed between two far-away objects. Subtracting vectors at distinct points, if you like." and they do this for the same reason that Carroll cites:

"In general relativity, you just can’t do that."

Here are Bunn and Hogg on this point:
(no math here, just plainly written words.)

" We wish to make clear at the outset that we are not suggesting any doubt about either the observations or the general-relativistic equations that successfully explain them. Rather, our focus is on the interpretation: given that a photon does not arrive at the observer conveniently labeled “Doppler shift,” “gravitational shift,” or “stretching of space,” when can or should we apply these labels?

Arguably an enlightened cosmologist never asks this question. In the curved spacetime of general relativity, there is
no unique way to compare vectors at widely separated spacetime points, and hence the notion of the relative velocity
of a distant galaxy is almost meaningless. Indeed, the inability to compare vectors at different points is the definition of a curved spacetime.
---------------
(footnoted referernce numbers
[1, J. C. Baez and E. F. Bunn, “The meaning of Einstein’s equation,” Am. J. Phys.73, 644–652 (2005).

2, S. Carroll,
Spacetime and Geometry: An Introduction to General Relativity (Benjamin Cummings, San Francisco, 2003).

3, B. F. Schutz, A First Course in General Relativity
(Cambridge University Press, Cambridge, 1985)

4 C. W. Misner, K. S. Thorne, and J. A. Wheeler,
Gravitation (W. H. Freeman, New York, 1973). ]

In practice, however, the enlightened view is far from unive
rsal. The view presentedby many cosmologists and astrophysicists, particularly when talking to nonspecialists, is that distant galaxies are“really” at rest, and that the observed redshift is a consequence of some sort of “stretching of space,” which is distinct from the usual kinematic Doppler shift. In these descriptions, statements that are artifacts of a particular coordinatesystem are presented as if they were statements about the universe, resulting in misunderstandings about the natureof spacetime in relativity."

By proximity1 (not verified) on 02 Feb 2016 #permalink

Owlmirror, thanks for the interesting and relevant link.

Proximity, I think Dr. Carroll is saying that, since the relativistic Doppler effect is calculated using a relative velocity between the observer and the photon source, and relative velocities over large distances are problematical in GR, using the RDE to explain the cosmological red-shift may actually confuse some students.

Also in my opinion, there has been some goal-post shifting since the original topic of dark-energy accelerated expansion came up, but I will leave that for Eric to pursue, if he still has the patience.

@104: goal-shifting implies malice or intentional rhetorical device. I'm not sure I would say that. But we have certainly drifted in terms of claims.

Proximity, the claim of yours that first started this discussion was in @34, where you claimed the expansion could not go on forever because that is logically impossible. You think if that were to happen, all particles would be separated by infinite distances right now. I have tried multiple times and in multiple ways to show you this assertion isn't right.

1. There is nothing logically impossible about the notion of indefinite expansion. Nor does the concept require that the universe at some specified time t be infinitely dilute.

2. Our empirical understanding of the four forces of physics leads us to believe that the dispersal of things like galaxies that we see will not inevitably be mirrored on smaller scales on down to subatomic particles. If lambda increases, that can happen. If lambda stays constant, then large structures will continue to expand away from each other, but things like solar systems and molecules and nuclei will remain stable because the forces holding them together are orders of magnitude stronger than whatever it is that is pushing things apart on the large scale.

3. Even if the expansion increases to the point where a big rip happens, so what? You seem to be arguing that that can't be possible or it would've happened already. I'm not sure how you get from "big rip possible" to "can't be possible or we'd already be there."

4. Nothing in the B&H article supports any of your claims I've discussed in points 1-3 above. Yes, my initial reading was incorrect. Yes, it isn't crankery. Yes, I'll accept their contention that the rubber-sheet-expansion model is a poor analogy that doesn't capture relativitiy's details correctly. None of that supports your claim than continued expansion is impossible. If you think it does, please tell me how.

For the long and expanding record, I don't mean to imply malice by the term "goal-shifting", only that the goal posts have moved (in my opinion), for whatever reason. Evolution produces creatures with imperfect memories and maybe the original post locations have been forgotten.

Likewise, there's not a lot of contradiction between atheism and a conception of God as "the goodness in a humanity", or some such waffle.

Which is why I have to qualify. When I say I'm an atheist, I mean that I am persuaded that when people pray, there's actually nothing at the other end of the phone.

By Paul Murray (not verified) on 02 Feb 2016 #permalink

@ 105 :

I have not intended any goal-post moving. But I think that a large part of this discussion has involved misinterpretations of the significance of certain key terms.

I don't associate the terms “infinite” or “infinity” with any physical reality. I regard these terms as proper to a state, a condition which is unique and without scope or scale. A condition which precludes change, movement, quantity, magnitude, locale or discretness. For me, infinity has neither boundary or point of origin or terminus. So a universe that expands “forever” would still not, as I see things, qualify for the term “infinite.”

I believe ours is a finite universe. That means limits on everything in it and about it and it means that I regard reality as coextensive with this universe. There is no reality beyond the confines of the universe. I also think it makes sense to see the Big Bang as a feature of a cycle. In this respect, I am liable to face the objection that these cycles themselves are infinite and so therefore I subscribe to a universe infinite at least in duration—punctuated by cyclical expansions and collapses. I accpet that as true—one could argue that the cyclical universe is a form of infinie universe. But for me this makes nonsense of the term universe—and, in a certain informal sense, nonsense of the term “reality.” If the universe (and, with it, reality) means that the intsant immediately prior to a Big Bang “explosion”-like expansion is just as much a universe as is the state in which we see things today, I think this reduces universe to an absurdly tiny idea—though a fully real one, never the less.

If the universe is not cyclical in the sense I have in mind, with repeated bangs and expansions followed eventually by a general collapse, then I suppose it must have always exited as a very large space—conceivably an expanding space but still not an infinity—note, one cannot properly apply the term “space” to “infinite.” Infinite is not, I repeat, not, a “space.” In this view, I suppose that matter and energy have been ceaselessly alternating as particles combine into larger matter and larger matter disintegrates into particles. I accept that a possibility but I discount it. What, in this case, “fuels” the general universal expansion? (see this question below).

It may be that the present expansion could continue without limit or end. I grant that is not an impossibility though I doubt that this is what we should expect. Even so, this unlimited expansion would not constitute an infinite condition or infinity since it would be bounded by an origin point—unless a cyclical view is taken.

I think Hogg and Bunn reject the interpretation given by Perlmutter for the supposed cosmological shift. They view it as a regular Doppler red- (or blue, as the case may be) shift and I agree with that view. I gather that this means then that there is no place for superluminal speeds or for some recent increase of acceleration in the expansion of the universe and, least of all, for any “stretching of space”--meaning that the volume of space itself is increasing without any relative motive through that space. Instead, if the objects and contents of the universe are growing more and more distant frrom all surrounding points, that is because there is movement through this space by these objects and not because “space itself” is dialating” absent any movement at all.

Though I don't expect to live long enough to see it, I think that one day, Perlmutter's Nobel prize shall be seen as a huge blunder on the part of the awarding committee. His ancestors, showing it to others, will have to explain that the work for which it was awarded turned out to be the source of a completely mistaken interpretation of physical events.

A question for you concerning this, and especially the emphasised part

" 2. Our empirical understanding of the four forces of physics leads us to believe that the dispersal of things like galaxies that we see will not inevitably be mirrored on smaller scales on down to subatomic particles. If lambda increases, that can happen. If lambda stays constant, then large structures will continue to expand away from each other, but things like solar systems and molecules and nuclei will remain stable because the forces holding them together are orders of magnitude stronger than whatever it is that is pushing things apart on the large scale. " (Emphasis added)

I'd like to know what you take this "whatever it is that is pushing things apart on the large scale" to be. For me, it's the residual momentum from the last Big Bang (cyclical, in my opinion) event. If not, what is it in your opinion?

By proximity1 (not verified) on 03 Feb 2016 #permalink

I don’t associate the terms “infinite” or “infinity” with any physical reality

The wavefunction of the 1s hydrogen electron is given here. There is no limit on r (radius); the wavefunction value approaches zero as r approaches infinity, but essentially, the wavefunction of the electron goes on forever. If you're saying all of quantum mechanics is wrong because such an infinite wavefunction cannot be real, I hope you have something more than just your personal gut feeling or beliefs about infinity to support that.

I’d like to know what you take this “whatever it is that is pushing things apart on the large scale” to be.

I don't know. But unless the magnitude of whatever it is changes, it will not tear nuclei, molecules, and many gravitationally bound systems of particles apart. This is basic high school physics: you have a force vector pointing in one direction and a second pointing in the other. If they are constant, the weaker one doesn't win no matter how much time passes.

Proximity:

"Instead, if the objects and contents of the universe are growing more and more distant from all surrounding points, that is because there is movement through this space by these objects and not because “space itself” is dialating” absent any movement at all."

Bunn:

“So I’d rather you not think of the Big Bang as an explosion “at a certain position in space”. It’s still true that it happened everywhere rather than somewhere. There’s no preexisting space into which stuff expands. For instance, if we imagine a closed Universe (i.e., one that has a finite volume today), its volume was smaller in the past, approaching zero as you get closer to the Big Bang. So in that sense space really is expanding.”

I don't think Bunn and Hogg agree with Proximity. In addition, there is the empirical fact, discovered by Hubble, that the further away distant galaxies are from us, the faster they are moving, in all directions. Residual motion from an explosion would not do this. An expanding universe (whether by the stretching of existing space or the addition of new space, see my 1D example) would.

Jim @ 110
absent any movement at all.”
Bunn:
“So I’d rather you not think of the Big Bang as an explosion “at a certain position in space”. It’s still true that it happened everywhere rather than somewhere. There’s no preexisting space into which stuff expands."

Yes, I read that already. Where have I rejected this? Nowhere.

Same goes for the following.
I have failing eyesight, a dodgy connection that comes and goes and I type this on a tiny screen. And your comments call on me to repeat what I've already written. No more!

"For instance, if we imagine a closed Universe (i.e., one that has a finite volume today), its volume wa

Gs smaller in the past, approaching zero as you get closer to the Big Bang. So in that sense space really is expanding.”

By proximity1 (not verified) on 03 Feb 2016 #permalink

@111: could you explain what you see as the difference between dialating and expanding then? Because in @108 you stated you don't think space is dialating but now in @111 you say you do accept that it expands.

Proximity, all the public libraries where I have lived (a sample of four, in NY and Ohio) have 12-20 desktop computers available to the public (with a library card, freely available in most places), with Internet connections. If this is not the case where you live, I would consider buying you a laptop computer (to be picked out by you at Amazon.com and shipped by me to any address where you could pick it up) at a reasonable price, provided you have an Internet provider for it.

My own eyesight is not good, but on my laptop I set the browser "zoom" at 150%.

I am not comfortable giving out my email address here, but could get a shipping address (not necessarily your personal address) from you by downloading a text file that you have placed on a free online storage site (e.g., Dropbox, Box, wikisave) and linked to in a comment.

P.S. On a desktop or laptop you can copy and paste text from one place to another easily. Or on a tablet, I suppose, but I have never had a tablet.

Re: "not dilating absent any motion" could mean

a) there is no dilation (expansion) of space, only objects moving away (from every other object in all directions everywhere somehow). or

b) dilation does occur but only where objects are moving.

a) contradicts Bunn's statement that objects from the Big Bang did not move into pre-existing space, and that the volume of space has increased since the Big Bang.

b) is I think the opposite of what Bunn & Hogg think, as I explained in #98. Expansion of the universe occurs by the additional of new space, which cannot be at the location of existing particles (in motion or otherwise) - since wherever an existing particle is is (double "is" intentional, sorry) existing space (new space must be formed and moved into before a particle can exist there). This addition of space makes distant objects move away in all directions from any reference point, at larger velocity the farther they are away (as illustrated in #98), which explains Hubble's observations. The fact (if it is one) that the new space does not form where an existing particle is explains why photons are not being stretched to produce the cosmological red-shift. (This again is an analogy - the reality as far as we know is contained in the equations of General Relativity, which Bunn & Hogg & Carroll and about 99% of all physicists agree on, in the non-quantum realm.)

118:

Yes, I accept the view--with Bunn and Hogg and so many others--that the universe is increasing in its volume, its size. I accept, too, that this increase, while movement, does not amount to any moving into other, preexisting space. No such space (or reality) exists as I believe these people see it. The increase in volume of the universe is its own "outward" movement by which physical reality (spacetime) increases (and later, collapses). There is nothing--not even "emptiness"--preexisting this increase in volume which is why I say I agree that a Big Bang event does not occur "in" any surrounding spacetime. The events (expansion and collapse) and spacetime are coeval.

I don't agree that at the "outer edges" of the visible universe there is a relatively faster expansion of the universe than what is observed elsewhere. I think that the appearance of such is a misinterpretation of the data on which this phenomenon is based. A Doppler shift, but not any special increase in the otherwise found rate of expansion. So, while matter is moving apart in all directions, it is this matter's moving that accounts for the increasing distances, not a dilation of spacetime that leaves the physical entities in unchanged relative positions from some frame of reference.

----

I do use desktop computers public facilities. But the time available on these is one hour per locale, For further use, I have only a frustrating little "stupid-phone."

By proximity1 (not verified) on 03 Feb 2016 #permalink

Relativity assumes that space is homogeneous and thus the expansion rate is the same everywhere at a given time. However, uniform spatial expansion causes objects to move away from each other in all directions, at faster apparent relative velocities the farther they are apart. The original astronomical observations which suggested that this is in fact happening were made before General Relativity was formulated and were based entirely on Doppler-shift calculations - far distant astronomical objects had larger Doppler shifts the farther they were away and thus larger apparent relative velocities.

Given the GR equations and derivations based on them, the astronomical data is now interpreted to show that the spatially-uniform expansion rate has increased over time. This is supported independently by the fact that the age of the universe since the Big Bang would be too short for the generations of star evolution which are observed if the current expansion rate was constant or decreasing over time.

This is (roughly) the state of the art/science as I understand it. Changes to this understanding would have to account for all the reams of astronomical data which the above theory explains, in some other way. It would certainly produce a Nobel Prize, if you or anyone is able to formulate an alternate theory which explains the data better.

I understand that an hour at a time in a library makes it inconvenient to research all the background of the above synopsis, so my offer to pay for a laptop (which could be used in a library for internet access with no one-hour limit) stands. I will leave it to you to propose how this can be done without exposing either of our private information unduly.

Jim @ 113: You are extremely kind to offer this. That offer went right by me on the first look at your post. Later, I thought, "What's all this about a shipping address?" And only when I took a closer, (better) look did I read of your offer.

It's extremely kind but for reasons of my peculiar circumstances, I think it's best not to take advantage of your generosity. With a near certainty, I'd lose, break or find the computer stolen. I don't have the means to keep it safe and in the circumstances, it's much better that I use public terminals which I need not maintain or keep safe.

It's a very long time since I had to fiddle around with file back-ups, installations, updated releases, etc. Good riddance to all that! ; ^ )

I found the "stupid phone" lying on the ground one evening as I was leaving a library. No one was in sight and I took it straight inside to leave with the staff to be put in the lost-and-found. When, two weeks later, it was still there, I asked for it as though I'd lost it and it was given to me. I only use it for internet browsing--and when I need to experience be infuriated by recent technological progress.

By proximity1 (not verified) on 04 Feb 2016 #permalink

@ 117
That's a helpful and interesting synopsis. Thanks.

I think I recall that from time to time since the late 19th and early 20th C, astronomers/cosmologists have revised their estimations of the age of the universe--adding age each time.

"Given the GR equations and derivations based on them, the astronomical data is now interpreted to show that the spatially-uniform expansion rate has increased over time. This is supported independently by the fact that the age of the universe since the Big Bang would be too short for the generations of star evolution which are observed if the current expansion rate was constant or decreasing over time."

Rather than suppose that the rate of expansion is increasing, is it not an alternative to posit that the universe is (again) larger (and so, older) than previously thought? Technical means allow the detection of distant objects or radiation only up to a certain limit--after which it's really not know what if anything, lies beyond the range of the detection, right?

One of my hunches--perhaps ridiculous--is that the residual propulsion from the "last" Big Bang event is responsible for the expansion going on. You countered that in such a case, there could be no subsequent increases in the rate of expansion and I agree of course. So I rather think that the indications of the rate of increase may be mistaken interpretations of data--only apparent, rather than real. Perhaps the residual propulsion is also the source of or related to gravitational influences so that, without the presence of the residual propulsion, matter would would "fall back," collapse toward a common point rather than remain drifting or static.

In the references at the end of Bunn and Hogg's paper are a few papers by

M. Chodorowski, “Is space really expanding? A counterexamp
le,” Old and New Concepts of Physics
4
, 15–33 (2007).
12

M. J. Chodorowski, “A direct consequence of the expansion of
space?,” Mon. Not. Royal Astron. Soc.
378
, 239–244 (2007).

By proximity1 (not verified) on 04 Feb 2016 #permalink

I don’t agree that at the “outer edges” of the visible universe there is a relatively faster expansion of the universe than what is observed elsewhere.

It is an observed fact that things further away from us are (generally) moving faster away from us. AFAIK nobody disputes this, not B&H. Explaining the red shift as a Doppler shift does not remove the fact that the red shift is observationally higher for objects further away.

Rather than suppose that the rate of expansion is increasing...

AFAIK, nobody is supposing that. See JimV's post @98 and especially his a,b,c, example. Sitting at point 1, I see the distance between me and point 2 increasing by "a" per year. I see the distance between me and point 5 increasing by a+b+c+d per year, four times faster because it is four times further away. A constant expansion rate in this example means a=b=c=d. It does not mean I expect point 5 to be moving away from me approximately as fast as point 2. That would not actually be a constant expansion rate, it would be a decelerating one (AIUI, leading eventually to a 'big crunch').

Eric @ 120 :
"It is an observed fact that things further away from us are (generally) moving faster away from us. AFAIK nobody disputes this, not B&H."

Very interesting. Why are (should) the more distant objects moving away faster than nearer objects? I suppose there's a working theory to account for this difference, right? Is this observation at odds with GR?

I take it that this, from Jim, is a hypothetical example for purposes of illustration, not an actual account of valid real rates, right?

"An observer in 1 sees that an observer in 2 has moved away at a velocity of 1 (space unit per unit time), 3 at 2, 4 at 3 and 5 at 4. An observer at 3 sees that 1 has moved away at -2 velocity, 2 at -1, 4 at 1, and 5 at 2 (just like Hubble expansion). But the space-units themselves have not stretched – new space has been added."

And so I agree--in the sense which B & H intend, "new space" has been "added", i.e. the universe is relatively larger as time proceeds. That is one point. The rate of expansion is the other key factor.

By proximity1 (not verified) on 04 Feb 2016 #permalink

Proximity, I am sorry to hear that your circumstances do not allow you to own a laptop. A tablet would be smaller and easier to carry and might be easier to use on the Internet than a phone - I don't know because I have never tried one. I would like to suggest that you try some tablets at Best Buy and see if one might suit you. You could also look at the laptops since I think some of them now are almost as small as a tablet. If you find one that you like, I could probably find an online source for it which could ship it to you.

As I told a nephew, I was a poor student once, and there will be poor students when you are my age. (The "pay it forward" philosophy.)

Jim @ 122:
Thanks again for the offer. Again, I believe it wouldn't be right to accept. The reasons are idiosyncratic ones. I'm far from any Best Buy by choice. And I think in my case you'd be paying "backward" as I'm not young poor student but an old one. That's as I've chosen so you shouldn't feel concerned. This little device is slow and I type quickly and with many errors. There's a work-around though: a crude notepad editor is more easily functional and I can compose, copy & paste from it.

--
I owe Eric a reply to his @ 109:

Too tedious now to cut and paste his comments; I'll just answer Instead:
Yes, it follows from my previous comments that I think of such infinite wave functions (to the meagre extent I "understand" them) as theoretical abstractions which have no actual role (as infinite, mind you) in physical reality. Or just plain reality. And, "no," I have nothing more than you mentioned to support that view. I suppose you'll find that ridiculously arrogant or naive or something worse but these are my answers to those questions.
I have a post with links waiting in the moderation queue. It ought to appear before long.

By proximity1 (not verified) on 04 Feb 2016 #permalink

"Rather than suppose that the rate of expansion is increasing, is it not an alternative to posit that the universe is (again) larger (and so, older) than previously thought?"

Physicists do suppose that the universe is bigger than we can see, but what we can see is tremendously large enough that it seems reasonable to also suppose that what we don't see looks much like (e.g., contains the same observational data) as what we do see.

On the age of the universe:

http://map.gsfc.nasa.gov/universe/uni_age.html

"Measurements by the WMAP satellite can help determine the age of the universe. The detailed structure of the cosmic microwave background fluctuations depends on the current density of the universe, the composition of the universe and its expansion rate. As of 2013, WMAP determined these parameters with an accuracy of better than than 1.5%. In turn, knowing the composition with this precision, we can estimate the age of the universe to about 0.4%: 13.77 ± 0.059 billion years!"

"How does WMAP data enable us to determine the age of the universe is 13.77 billion years, with an uncertainty of only 0.4%? The key to this is that by knowing the composition of matter and energy density in the universe, we can use Einstein's General Relativity to compute how fast the universe has been expanding in the past. With that information, we can turn the clock back and determine when the universe had "zero" size, according to Einstein. The time between then and now is the age of the universe."

And a note on the reliability of Einstein's General Relativity equations, which were used to calculate the age of the universe from the WMAP data:

http://www.forbes.com/sites/startswithabang/2016/02/03/the-cosmic-gift-…

"Einstein predicts that these pulsars magnetospheres should eclipse the other, and that the pulses of one should be hidden by the other for about 30 seconds every few hours. In addition, the orbits and the magnetosphere eclipses should precess by a specific rate, also predicted by General Relativity. Did you bet on Einstein? You should have!"

"And one of the fun things that was a bit unexpected: during the eclipse, a little bit of flux from the background pulsar sneaks through! This was a surprise, so Kaspi and her collaborators modeled the magnetosphere and saw what came through. Did you bet on Einstein again? This is a good theory, is my point: it’s celebrating its 101st anniversary this year, still being tested in new ways, and still coming up correct!"

@ 124:"Physicists do suppose that the universe is bigger than we can see, but what we can see is tremendously large enough that it seems reasonable to also suppose that what we don’t see looks much like (e.g., contains the same observational data) as what we do see."

I consider that a huge assumption. How big? As big as the as-yet-unmapped universe. The problem again is a logical one--in this case, begging the question. We wonder: what Is the umapped universe like? --must entail "how big is the universe beyond what we can see?" Another way of asking it is, "how large is our visible universe relative to that part beyond our scope?" To reply that we can safely suppose that the unseen resembles the known because the known is so "very large" is to beg the question. We haven't yet any way to confidently assert that our visible universe is "very large." Only earlier this week I was told that it's perfectly fine to consider the universe as infinite. In that case, our visible part would be, relatively, 'infinitely' small, wouldn't it? Why shouldn't we suppose that possibility, too?

By proximity1 (not verified) on 05 Feb 2016 #permalink

Somewhat off topic here, but the thread that it is on topic for has been closed to comments.

Our host's paper on mathematical anti-evolutionism is (sort of) online at
http://link.springer.com/article/10.1007/s11191-015-9801-7

Although, with an access charge of $39.95, it would appear Springer doesn't actually want anyone to read it.

The terms "edge of the universe" have been used. There are no edges, according to GR. Space is homogeneous. There is an edge that is as far as we can see due to the finite speed of light, but observers at that "edge" would also see galaxies in all directions. If finite, the universe must be a self-enclosed shape. My first thought was the 3-dimensional surface of a (expanding) 4-dimensional hyper-sphere, but after some Googling I find that the smart money is on a 3-torus, which is a cube with opposite faces connected.

One can suppose whatever one likes, but the Theory of General Relativity was derived in part on the assumption of homogeneous space, and so far in 101 years of ever-refined technology for making astronomical observations, it has been amazingly correct, and GPS devices would not work without using its calculations. Creationists say, "Logic says that you can't prove my god doesn't exist - it could be hiding in some unknown part of the universe which has different rules." Science says, let's look at all the evidence and use the Theories that fit them the best. This will necessarily not include evidence from parts of the universe that we will never see.

My parents used to say, "you can lead a horse to water, but you cannot make it drink". It is past time that I stopped writing so many comments at this site and on this thread in particular. Every question raised here can be answered by experts who have spent their carriers on the subjects with a little Googling.

Yes, it follows from my previous comments that I think of such infinite wave functions (to the meagre extent I “understand” them) as theoretical abstractions which have no actual role (as infinite, mind you) in physical reality. Or just plain reality. And, “no,” I have nothing more than you mentioned to support that view. I suppose you’ll find that ridiculously arrogant or naive or something worse but these are my answers to those questions.

Well, let's instead say that I find it the argument from incredulity and thus not compelling. You're claiming the most tested theory in science is wrong, basically for no stronger reason then you don't like what it concludes about particle wavefunctions. That's fine, it won't be the first time a layperson has objected to some aspect of QM out of incredulity. But suffice to say that no scientist is going to give any weight to that sort of objection.

The persuasion of one's correspondent should not, i believe, be the sole or even the primary expectation here. These are controversies of theory and interpretation which divide even the most advanced experts in the science concerned. I don't believe that there is no cause for regret if, after exposing all of one's evidence and reasoning, opposing views are not relinquished by one's correspondent.

If a horse may be allowed todrink when he's in need of water and abstain when not, then all I ask and expect here is the similar right to take the evidence and consider it as it most makes sense to me and, if I'm simply "not thirsty," if I remain unpersuaded at the end of the treatment, to be accorded that as my right. As long as our views are allowed a place to be exposed to the consideration of others, we ought to, I think, regard our time and efforts as well spent even if there is no overturning of opinion on the part of our correspondents. That omission does not prove that the efforts had not been afforded any appreciation.

By proximity1 (not verified) on 09 Feb 2016 #permalink

@ 129:

( a voice from the audience) : "What if they're not simple?"

Einstein : "Then I would not be interested.

------------------

(from page 148, The Character of Physical Law :

...An important point about this intelligence is that it should not be sure (emphasis added) ahead of time what must be. It can be prejudiced, and say 'That is very unlikely, I don't like that'. Prejudice is different from absolute certainty. I do not mean absolute prejudice- just bias. As long as you are only biased it does not make any difference, because if your bias is wrong a perpetual accumulation of experiments will perpetually annoy you until they cannot be disregarded any longer. They can only be disregarded if you are absolutely sure ahead of time of some precondition that science has to have. ...

I admit that my prejudices regarding the incompatibility of infinity with physical reality are very close to complete. I also admit that the nature of these things is such that they can probably never be demonstrated one way or another in their truth or falsehood. But I think that the logic of the position I hold is quite compelling.

If physical reality is finite, it seems to me that, then so, outside of mathematical abstractions used for theoretical musings, is the actual reality of infinite wave functions. Such functions can never produce more than the tiniest fraction of the possibilities entailed before, in nature, a function collapses in one determined state or another. To take its infinite extent seriously, we must allow and admit that, at any given determined point of the function's closure, there reamined "an infinity of unattempted possbilities" -- "possibilities" which, it must be admited, never had any realistic possibility to be resolved in a determined outcome.

I see no logical escape from that conclusion though I would welcome anyone's pointing one out to me.

By proximity1 (not verified) on 09 Feb 2016 #permalink

I see no logical escape from that conclusion though I would welcome anyone’s pointing one out to me.

Sure. There's three problems. First one:

If physical reality is finite...

You don't know if it's finite or not. None of us do. So your logically inescapable argument is based on a premise that you don't know the truth status of. This means your argument may only be valid, it is not necessarily sound.

Problem two:

functions can never produce more than the tiniest fraction of the possibilities entailed before, in nature, a function collapses in one determined state or another. To take its infinite extent seriously, we must allow and admit that, at any given determined point of the function’s closure, there reamined “an infinity of unattempted possbilities” ...

Circular argument. The fact that infinite wavefunctions imply infinite possibilities that are never actualized is only a "flaw" if you start with the presumption that infinities are bad/unallowed - which is what you are trying to assert. IOW this criticism is only a criticism if you start out assuming the point you want to show. Remove the assumption/premise that infinities are bad, and your entire paragraph above becomes a non-sequitur comment rather than an argument.

...“possibilities” which, it must be admited, never had any realistic possibility to be resolved in a determined outcome.

This is empirically untrue. Every time we take data on, for example, a radioactive isotope's half-life, we get a smooth exponential curve fully consistent with the predictions of QM. As long as we care to look, we will continue to see low probability events occurring in exactly the ratio we would expect them to occur if our math is correct. There are no boundary conditions or cut-offs that would be predicted or consistent with your notion of finite wavefunctions. Now of course we can't observe a radioisotope for literally forever, and of course we have instrumentation limitations we must deal with, so like everything else in science, our conclusion is provisional and subject to being overturned should new evidence arise. But nevertheless, the best conclusion we have from the evidence we have is that you are wrong, and that low probability QM interactions do occur at exactly the frequencies predicted/consistent with current wavefunction math.

@ 131 :

I havre a naive person's question for you:

Concerning these infinite wave functions, I assume that the term "infinite" applies to the fact that there are theoretically--and I gather, for you, also, not merely theoretically but in actual physical fact--an infinite number of "solutions" or values by which the function's terms are valid--true or false? IOW, there are an infinite number of "solutions" to the function and it closes or is said to collapse when one of these is (in whatever manner this occurs) is "determined." Do I have that roughly correct?

By proximity1 (not verified) on 09 Feb 2016 #permalink

@ 132 :

"There’s three problems. First one:
(citing me) "If physical reality is finite…"
"You don’t know if it’s finite or not. None of us do." (does)

Right, It's a working assumption. But, imagine, please that physical reality is infinite. Have you done this? Can you do this? The implications are properly incredible. Again, I say that here the work of Jagjit Singh are very interesting. He has discussed the problems of this topic. If you can, you should try and locate his Dover texts (Great Ideas of...) and read the relevant parts.

Great Ideas of Modern Mathematics (Dover Books on Mathematics)

An infinite physical universe--has what? Finite or infinite matter in it? If finite, then the materially "occupied" part of this universe is literally "infinitely tiny"--and we occupy that part.

Second, how would one account for a single-universe event on such conditions? That is, there are no cycles, the universe either "began" at some point (your view?) or it is eternal as welll as infinite, If the latter, then do we suppose that it has been in expansion eternally or not? Does it both expand and contract? If so, how is this other than a form of cyclical universe? In such a universe, what possible sense does it make to speak, as scientists routinely do, of the "early universe" or of "looking back into time" as their exploratory instruments take in and analyze the most distant light from the "farthest reaches of the limits of our view" ? That "time" would, it seems, be neither any earlier or any older than any other in the rest of the universe. In an enternal (i.e. infinite, how else?) universe, how can there possibly be "younger" and "older" parts of the same infinite system?

By proximity1 (not verified) on 09 Feb 2016 #permalink

"the work of Jagjit Singh are very interesting..."

or even is very interesting, too! ;^)

By proximity1 (not verified) on 09 Feb 2016 #permalink

I assume that the term “infinite” applies to the fact that there are theoretically–and I gather, for you, also, not merely theoretically but in actual physical fact–an infinite number of “solutions” or values by which the function’s terms are valid–true or false?

In the case of the 1s electron, it means the wavefunction has a nonzero value for all values of r (except r=0? I forget. It may have a node of zero probability at r=0), extending out to infinity.

imagine, please that physical reality is infinite. Have you done this? Can you do this? The implications are properly incredible.

Thus, the name "argument from incredulity." Pointing out the implications are incredible or absurd isn't an argument against them being right. Many people find the concept of a single particle going through two holes simultaneously to be incredible, but their incredulity doesn't change the results of the two-slit experiment. The universe may very well be incredible or absurd according to human sensibilities. Nowhere is it written that the universe's governing laws must be ones that seem normal or sensible to humans, and that includes the humans going by the internet aliases 'eric' and 'proximity1'.

imagine, please that physical reality is infinite. Have you done this? Can you do this? The implications are properly incredible.

"Thus, the name “argument from incredulity.”

I mean something specific by incredible here. I mean that, by your own terms, you cannot imagine a coherent, logically consistent infinite universe.

If you try, you shall contradict yourself in ways that are patently ridiculous--again, by your own terms' meanings. (This, in essence, is the point which Jagjit Singh makes in the chapter where he considers these questions.)

That, I suppose, is why you've ignored every single question I put above seeking your clarifications of just what such an infinite universe would be like.

1) An infinite physical universe–has what? Finite or infinite matter in it?

2 ) how would one account for a single-universe event on such conditions? That is, there are no cycles, the universe either “began” at some point (your view?) or it is eternal as welll as infinite,

3 ) If the latter, then do we suppose that it has been in expansion eternally or not?

4) Does it both expand and contract? If so, how is this other than a form of cyclical universe?

5 ) In such a universe, what possible sense does it make to speak, as scientists routinely do, of the “early universe” or of “looking back into time” as their exploratory instruments take in and analyze the most distant light from the “farthest reaches of the limits of our view” ? That “time” would, it seems, be neither any earlier or any older than any other in the rest of the universe. In an eternal (i.e. infinite, how else?) universe, how can there possibly be “younger” and “older” parts of the same infinite system?
________________________

By proximity1 (not verified) on 10 Feb 2016 #permalink