Is the Multiverse Real?

Discover Magazine has an interesting article up discussing a perennial favorite: the fine-tuning of the universe for life. I got a bit nervous when I saw the title:

Science’s Alternative to an Intelligent Creator: the Multiverse Theory

That makes it sound like scientists devised the multiverse idea strictly as a desperation move to counter all that annoying God-talk. In reality physicists have been seriously discussing the idea of a multiverse for decades, and quite a lot of work in physics is pointing in that direction. The multiverse does seem to follow naturally both from recent work in string theory as well as the inflationary Big Bang theory. This is a considerable improvement over the nothing at all on which the God hypothesis rests.

The article’s beginning sadly plays up the desperation theme:

Call it a fluke, a mystery, a miracle. Or call it the biggest problem in physics. Short of invoking a benevolent creator, many physicists see only one possible explanation: Our universe may be but one of perhaps infinitely many universes in an inconceivably vast multi verse. Most of those universes are barren, but some, like ours, have conditions suitable for life.

The idea is controversial. Critics say it doesn’t even qualify as a scientific theory because the existence of other universes cannot be proved or disproved. Advocates argue that, like it or not, the multiverse may well be the only viable non religious explanation for what is often called the “fine-tuning problem”–the baffling observation that the laws of the universe seem custom-tailored to favor the emergence of life.

This is a common trope in discussions of this subject, but it seems a bit off to me. Surveying what we know of our universe, it seems that the vast, vast majority of it is not hospitable to life. In the incredible vastness of space we know of one little planet that can sustain life over part of its surface some of the time. That doesn’t look like a universe primed for life. It looks like a universe where life won the lottery.

Happily, from here the article actually gets quite good.

Linde has spent much of the past 20 years refining that idea, showing that each new universe is likely to have laws of physics that are completely different from our own. The latest iteration of his theory provides a natural explanation for the anthropic principle. If there are vast numbers of other universes, all with different properties, by pure odds at least one of them ought to have the right combination of conditions to bring forth stars, planets, and living things.

“In some other universe, people there will see different laws of physics,” Linde says. “They will not see our universe. They will see only theirs. They will look around and say, ‘Here is our universe, and we must construct a theory that uniquely predicts that our universe must be the way we see it, because otherwise it is not a complete physics.’ Well, this would be a wrong track because they are in that universe by chance.”

Most physicists demurred. There wasn’t any good reason to believe in the reality of other universes–at least not until near the beginning of the new millennium, when astronomers made one of the most remarkable discoveries in the history of science.

Fascinating stuff. The article goes on to discuss the discovery of dark energy and recent work in string theory. Eventually we come to this:

When I ask Linde whether physicists will ever be able to prove that the multiverse is real, he has a simple answer. “Nothing else fits the data,” he tells me. “We don’t have any alternative explanation for the dark energy; we don’t have any alternative explanation for the smallness of the mass of the electron; we don’t have any alternative explanation for many properties of particles.

“What I am saying is, look at it with open eyes. These are experimental facts, and these facts fit one theory: the multiverse theory. They do not fit any other theory so far. I’m not saying these properties necessarily imply the multiverse theory is right, but you asked me if there is any experimental evidence, and the answer is yes. It was Arthur Conan Doyle who said, ‘When you have eliminated the impossible, whatever remains, however improbable, must be the truth.’?”

Quite right. The hypothesis of a multiverse explains a lot of data, and is strongly suggested by the best physical theories we have. I can understand why it is a bit frustrating as an hypothesis, since the best we can hope for is indirect evidence that it is correct. But what, exactly, is the reason for rejecting it? Is there any particular reason for thinking that the forces that created our own universe did not also create other universes at the same time? The multiverse hypothesizes more of the same. The God hypothesis hypothesizes something wildly and flamboyantly at odds with everything we know about the universe.

But some demur:

For many physicists, the multiverse remains a desperate measure, ruled out by the impossibility of confirmation. Critics see the anthropic principle as a step backward, a return to a human-centered way of looking at the universe that Copernicus discredited five centuries ago. They complain that using the anthropic principle to explain the properties of the universe is like saying that ships were created so that barnacles could stick to them.

“If you allow yourself to hypothesize an almost unlimited portfolio of different worlds, you can explain anything,” says John Polkinghorne, formerly a theoretical particle physicist at Cambridge University and, for the past 26 years, an ordained Anglican priest. If a theory allows anything to be possible, it explains nothing; a theory of anything is not the same as a theory of everything, he adds.

This is a bit rich coming from Polkinghorne, given that he has written several books arguing that it is the most natural thing in the world to believe in the Christian God. Talk about an hypothesis that allows you to explain anything!

But his comment is incorrect anyway. The multiverse hypothesis is not some all-purpose explanation for any current mystery of physics. It explains a very specific mystery, the illusion of fine-tuning, and does so with a very simple hypothesis that is strongly suggested by current theorizing.

As the article suggests, it is conceivable that we will someday obtain strong indirect evidence for the multiverse, but it is likely always to be speculative. It seems to me that in pondering these questions we are simply coming to the end of what physics can tell us. At some point the data runs out, and we must simply be content with a certain amount of mystery in our lives. I have no problem with that.

But I do have a problem with those who hypothesize into existence an all-loving, all-powerful God as a solution to any small mystery of life turning around and giving lectures on what is and is not a desperation move.

So let me close with a few words in defense of the multiverse:

Supporters of the multiverse theory say that critics are on the wrong side of history. “Throughout the history of science, the universe has always gotten bigger,” Carr says. “We’ve gone from geocentric to heliocentric to galactocentric. Then in the 1920s there was this huge shift when we realized that our galaxy wasn’t the universe. I just see this as one more step in the progression. Every time this expansion has occurred, the more conservative scientists have said, ‘This isn’t science.’ This is just the same process repeating itself.”

Take that anti-multiversers!

Comments

#1 Blake Stacey
November 12, 2008

“If you allow yourself to hypothesize an almost unlimited portfolio of different worlds, you can explain anything,” says John Polkinghorne, formerly a theoretical particle physicist at Cambridge University and, for the past 26 years, an ordained Anglican priest.

It’s true that a proposition which “explains everything” ends up explaining nothing, in that it gives you no predictive power; however, it’s not clear that multiverse proposals really fall into this category. There are stupendously many different arrangements of D-branes permissible in string theory, just as there are a zillion to the gajillionth power different possible solar systems which obey Newton’s laws. This does not necessarily imply that absolutely every possible observation is consistent with some arrangement of those basic components. Cross-sections of extraordinarily high-energy collisions are cited as an example; in any reasonable vacuum, they should be “stringy” rather than particulate. We might never be able to build an experiment which can access those energy levels, but that’s just our bad luck.

I get a little irked when people bring up the mass of the proton as an example of a fundamental constant which is (or appears to be) “finely tuned” for life. The proton mass is an emergent property of quark-gluon interactions! You couldn’t vary it without varying a whole host of other quantities in the bargain, since it is a function of more elementary parameters.

“If we had two space dimensions and one time dimension, we would not exist,” he [Linde] says.

But Turing-complete cellular automata could. Somewhere out there in the Multiverse, polygons are going about their Flatlander business, listening to circular priests with brains of a hundred trillion glider guns each pontificate on the impossibility of three-dimensional life. . . .

The religious air which always surrounds these discussions is exasperating. Suppose that a Fine-Tuner existed, a being who can create Universes and set the physical laws which operate within them according to the machinations of some intelligence. Either this Fine-Tuner exists in a Universe like our own, or it doesn’t. If its environment is like our own, then we have to explain where that environment came from, and we have gained nothing. If it exists in some entirely other fashion, then intelligence does not require physical laws like the ones which govern our Cosmos, and we have nothing to explain.

A few people are decent enough not to jump from grandiose, philosophical arguments about cosmology to the assertion that their particular god exists, with his preferences for headgear and the proper use of human genitals. All too many are eager to make that jump, telling us that yes, the Fine-Tuner or the Essential Precondition of Being had a son by a Jewish girl and then ensured that the son in question got nailed to a post at the age of thirty-three, and for whose sake we should vote for Sarah Palin in 2012.
#2 Blake Stacey
November 12, 2008

It is also entirely possible that fundamental physical laws could be changed, in a big way, without affecting the possibility of life as we know it. There’s a lot of dark matter out there, and we don’t know what it’s made of. It doesn’t interact too strongly with the sort of matter of which life like ours is made. The equations governing the behaviour of dark matter are as yet, shall we say, unilluminated; who’s to say which variations are consistent with the formation of stars, galaxies and carbon-based kittens, or if only one such variation is permissible?

Similar remarks can be made in other directions, for example concerning the three “generations” of quarks and leptons. The fundamental particles of matter (as we understand them today) come in three “levels”: we’ve got the electron and its partner neutrino, and a pair of quarks called up and down, and of these all familiar matter is made. But then we have the muon — a heavier version of the electron, of which I. I. Rabi said, “Who ordered that?” The muon comes with its own partner neutrino. At still higher energies, we find the tau lepton, with its neutrino — no, really, who ordered that?! The quarks likewise have their heavier cousins: first the charm and strange, then the bottom and top. Why three generations? This might be related to another puzzle, the fact that the Universe ended up with more matter than antimatter (once again, it’s hard to change one quantity without affecting others), but it’s hard to say what’s really the bedrock principle.

All sorts of little fiddlybits would seem to lack an anthropic explanation: for a while, we weren’t sure about the charge of the top quark. Was it 2/3 the proton charge or 4/3? Initial measurements were consistent with both possibilities, although 2/3 was the favourite based on the mathematical pattern of the Standard Model. Experiments at the Fermilab Tevatron gave a fairly solid answer in 2006, confirming the theoretical favourite of 2/3 — but top quarks are so hard to come by, it’s easy to wonder whether the difference would matter! Going the other way, can we start with the premise “carbon exists” and deduce the top quark’s mass and charge? What about the mass of the Higgs boson? The energy scale at which supersymmetric partner particles appear? Now, we are beyond the realm of easy cocktail-party philosophy: somebody will have to do the calculations!

To assert that physical laws could only be set up one particular way when we have only incomplete laws in hand seems more an act of vanity than anything else.
#3 cwfong
November 12, 2008

We can’t know that the cosmos is not endless without boundaries or that it hasn’t always existed, or that no calculating entities which we would regard as life forms exist somewhere, or that none of them assisted in the development of calculative and therefor purposeful entities in other parts of the cosmos, such as in our universe. And we can’t argue that any of the above is improbable, because for any of the above not to be possible is also not determinable. And in the vastness we can’t deny as possible, these other possibilities are inevitably probable.
#4 Blake Stacey
November 12, 2008

At some point the data runs out, and we must simply be content with a certain amount of mystery in our lives. I have no problem with that.

And in the meantime, we can apply the tools we have devised to condensed-matter physics accessible via tabletop experiments.
#5 Blake Stacey
November 12, 2008

cwfong:

It is also therefore extremely probable that the Universe and everything in it was created by a superintelligent shade of the colour blue.
#6 cwfong
November 12, 2008

A universe, but not probable that it was THE universe. Although someplace somewhere, the term blue refers to what humans have agreed to call red.
#7 Blake Stacey
November 12, 2008

But this particular superintelligent shade of the colour blue is, by definition, better at creating Universes exactly like ours than any other causal agent!
#8 Scott Hatfield, OM
November 12, 2008

Fine-tuning is at best suggestive of the possibility of design. It says nothing about the identity, nature or purpose of the source of design. The assertion that a designer is required to explain apparent fine-tuning can not be said to be a scientific statement. However, the assertions that multiple dimensions (as in string theory) or multiple universes are required to explain apparent fine-tuning strikes me as equally unscientific. I think that it was Torjborn Larson over at Pharyngula who pointed out to me that it is difficult to even decide in which direction you would go to invoke Occam’s Razor to decide which was ‘more scientific’: in one sense, a multiplication of universes (in Tegmark’s version, an INFINITE multiplication) greatly complicates any model that relies upon it. In another sense, however, the multiverse, creating itself, has the same fundamental simplicity as the ‘God’ of Spinoza or Einstein! Who decides?

I think I would like to see some highly-specific prediction of one multiverse theory or another be confirmed before I can get too excited one way or the other. Paul Davies has an extremely fair-minded summary of the related issues here, in which he concludes that despite ‘serious philosophical problems’ and a lack of progress (thus far), that ‘the multiverse idea has probably earned a permanent place in physical science’.
#9 cwfong
November 12, 2008

Blake, the next thing you’ll be telling me is that somewhere in the cosmos certainty prevails as an attainable goal!
#10 S Tombs
November 12, 2008

Jason,
You state regarding the multiverse theory: “It explains a very specific mystery, the illusion of fine-tuning” – surely the point in question here is whether or not the apparent fine-tuning is an illusion or not. Your describing it as an illusion suggests you start from that viewpoint, you have of course every right to do so, but don’t kid yourself that that’s science.

The concluding remark you make also doesn’t address the matter of whether or not the multiverse theory is science. It certainly is not science in any normal sense of the word, and it does seem to be the only answer materialists have to the design explanation.

Put simply, when it comes to explaining the apparent fine-tuning of the universe one way or another we leave science behind. Theists explain it by God – which goes outside the realms of science, while atheists use the multiverse, which also goes outside of the realms of science.

Your comment that “That makes it sound like scientists devised the multiverse idea strictly as a desperation move to counter all that annoying God-talk.” – yes it does, except not all scientists, I think you will find a significant number of proffessional scientists who find the multiverse concept a ‘frig’ to explain away data rather than explain it.

“The hypothesis of a multiverse explains a lot of data, and is strongly suggested by the best physical theories we have.” – I think you grossly overstate this. ‘Strongly suggested’ – this is clearly some new use of the word strongly.

“But what, exactly, is the reason for rejecting it?” – err, how about no real evidence.

“Is there any particular reason for thinking that the forces that created our own universe did not also create other universes at the same time?” – surely this is back to fron thinking, and is tantamount to religious people who come up with lines like ‘but you can’t prove God doesn’t exist’ – no but, but whether its God or the multiverse the burden of proof lies with those who assert existence.

“The multiverse hypothesizes more of the same. The God hypothesis hypothesizes something wildly and flamboyantly at odds with everything we know about the universe.” – this seems to be an attempt to assert that the multiverse is the more parsimonious explanation. As is so often the case, claims of parsimony often tell us more about the preconceptions of the person making the claim than they do about reality.

The multiverse is currently a wild idea that lies outside of science. It may be compatible with a few physical theories – but it is not supported by any real evidence.
#11 miller
November 12, 2008

Sorry Jason, but your essay here is really giving me problems. I agree with how you start out. The existence of a multiverse is not at all a desperation move to counter God. But then you go on about how the multiverse is so great because it counters the fine-tuning principle.

The existence of a multiverse is a scientific question, and cannot be judged through mere philosophical deliberations about the fine-tuning principal. If fine-tuning were the only evidence for the multiverse, the evidence would be quite weak indeed. It’s almost as weak as simply arguing that, “Throughout the history of science, the universe has always gotten bigger.”

The much stronger argument (which you acknowledged, but failed to emphasize) is that string theory and/or inflationary theory predict it. The existence multiverse is a prediction, not an explanation–whatever philosophical explanation we get out of it is just a perk.

‘Cause, you know, it may turn out that string theory is wrong. Not to go all Peter Woit on you, but it’s possible. And if string theory were true, and inflationary theory were true, AFAIK, they do not straightforwardly predict a multiverse. So if it turns out there is no string theory/inflationary multiverse, what would that say about the fine-tuning principle anyways? Nothing at all, I’d say. Who knows, maybe that just means there’s another kind of multiverse, or maybe there’s no such thing at all.

So what bothers me is that this article (or at least your excerpts) encourages readers to judge a scientific theory based only on their familiarity of the philosophical implications. What, so no understanding of cosmology is required?
#12 esmus
November 12, 2008

the only thing i know is that i know nothing.
http://esmus.blogcu.com
http://esmus.blogcu.com
http://esmus.blogcu.com
#13 alloytoo
November 12, 2008

We do not know the “tune” of the universe. We do not know if it’s good or bad or just so so because we have nothing to compare it to.

The moment you tell that to creationists they accuse you of trying to introduce Multiverse theory.

How they bridge the logical gap between a swathe of unknown probabilities and a proprosed Multiverse is quite beyond me.

Our Universe may well be a VW beetle, where a Ferrari is the ultimate in “Fine tuning”, but without a Ferrari to compare with, we simply do not know!
#14 MartinB
November 12, 2008

I have to disagree with the statement that themultiverse is
“strongly suggested by the best physical theories we have.”
It is not. people doing string theory realised that their theory (better called a hypothesis) cannot predict any numbers in our universe and is consistent with about 10^500 or so different universes.
They try to turn this failure into a virtue (not a bug, a feature) by inventing the multiverse.

So it is not exactly true that string theory “predicts” the multiverse in any sense.

As Feynman said (and this is still valid): “String theory makes exactly one prediction. This prediction is wrong.”
(Alluding to the number of dimensions they need, 10, 11 or 26 depending on which sort of string theory you look at).
#15 Dunc
November 12, 2008

in one sense, a multiplication of universes (in Tegmark’s version, an INFINITE multiplication) greatly complicates any model that relies upon it. In another sense, however, the multiverse, creating itself, has the same fundamental simplicity as the ‘God’ of Spinoza or Einstein! Who decides?

Well, given that we know that at least one universe exists, it is not unreasonable to suppose that there may be more – indeed, it’s far from obvious that there should be exactly one.

On the other hand, there is no good evidence (so far as I’m aware) for the existence of even a single God.

Therefore, proposing a multiplicity of universes is more parsimonious than proposing God.
#16 James McGrath
November 12, 2008

Perhaps a key point that ought to be made is that, whether one is speculating about God, gods, or a multiverse, one is engaging in philosophy, in metaphysics, rather than in scientific research per se. It may be philosophy or theology seeking to do justice to our best scientific knowledge – as indeed it should – but that doesn’t make it actual science.

Ultimately, if we have an infinity that gives rise to all sorts of universes, or a deity in the sense in which philosophy and classical theism use the term (as opposed to the popular highly personified depiction), we still have something the existence of which is just given, a brute fact that we cannot provide an explanation for. And that will for most of us who value science as a way of knowing be deeply disconcerting, since we’ve come to understand the universe so much better by seeking underlying causes.
#17 NoAstronomer
November 12, 2008

The hypothesis of a multiverse explains a lot of data

LOL WUT?
#18 David Marjanovi?
November 12, 2008

people doing string theory realised that their theory (better called a hypothesis)

No, it’s a theory, because the difference between theory and hypothesis is one of size, not one of certainty. Sure, the boundary is not defined, but anything that tries to explain “the universe and everything” is clearly a theory!
#19 Jason Rosenhouse
November 12, 2008

S. Tombs -

Fine tuning, in the sense that if we alter certain fundamental constants the result is a universe that could not sustain life, is a fact of the universe as we know it. The illusion to which I was referring was the idea that fine tuning implies an intelligent designer. You can remove the word “illusion” from my statement without changing my argument. The multiverse theory provides a neat explanation for how we ended up in a universe so fine-tuned for life.

I would agree that we can not disprove the possibility of multiple universes, so in that sense it is not scientific. The fact remains that we can still have strong evidence that the multiverse is real. Currently we have a lot of interesting evidence that suggests a multiverse. Hardly conclusive evidence certainly, but interesting nonetheless. The multiverse theory explains certain puzzling facts about the universe and follows naturally from two big theories in physics. That’s not nothing.

My observation that there is no good reason for rejecting the multiverse was not offered as evidence in favor of it. It is simply that I have known a lot of very sharp people (Martin Gardner is one, John Polkinghorne is apparently another) who regard the multiverse as not just unscientific, but actually ridiculous. Many of these people also suggest God as a non-ridiculous explanation for the same set of facts. I was merely wondering what the reason is for being so dismissive of the idea.

miller

I think I did emphasize the fact that the multiverse follows from both string theory and inflationary theory. I certainly mentioned it several times. String theory in particular is itself quite speculative, and I don’t regard the multiverse as a done deal or anything like that. I just think it has a lot more going for it than the religious alternative, and should not be dismissed as casually as it often is.

Scott Hatfield -

I would say Occam’s Razor is plainly on the side of the multiverse. Occam said that one should not needlessly multiply entities. He certainly did not mean that many universes is a more complex explanation than one God (as I believe Richard Swinburne has suggested), since by that interpretation we would do better to explain the clog in my drain by one gremlin as opposed to many atoms of hair and gunk. The multiverse tells us there is a lot more of the kind of stuff we see all around us. The God hypothesis simply invents an incredibly powerful being capable of doing things orders of magnitude beyond anything with which we have experience. I’d say one of those explanations is clearly simpler in Occam’s sense than the other.

James McGrath –

I agree that the existence of a multiverse just raises the question of where the multiverse came from (just as the God hypothesis raises the question of where God came from). I don’t find this disconcerting, however. In mathematics we prove theorems in terms of simpler theorems, and those theorems ultimately in terms of unproven assumptions. At some point you get down to statements so simple that you just accept them unproved as useful starting points. I see physics the same way. At some point you have pushed things back as far as you can go, and the explanations just have to stop. How could it be otherwsie?
#20 Aramael
November 12, 2008

The fact that the Universe appears “fine-tuned”[1] is compelling evidence for the non-existence of a designer. Consider, for example, the fact that there is a fusion pathway from hydrogen and helium to heavier elements. Why would a designer bother with all that nonsense, when they could just create heavy elements by fiat? Whereas in a Universe without a designer, you would expect to see such a pathway for each and every element we know of.

And if, for example, the process was shown to stop at iron nuclei, you would have to predict the existence of some sort of cataclysmic event that would result in the rest of the periodic table. If no such events were observed, you might start thinking about pulling the rosaries out.

QED.

[1] scare quotes are there because in a truly fine-tuned universe, there would be more chocolate
#21 Tulse
November 12, 2008

Fine tuning, in the sense that if we alter certain fundamental constants the result is a universe that could not sustain life, is a fact of the universe as we know it.

That assumes that a universe in which the fundamental constants are different is actually possible. I can imagine building houses out of whipped cream and fairy dust, but that doesn’t mean they would stand up — likewise, although we can speculate about changes to the fundamental constants that doesn’t mean that they aren’t intimately related in a way we currently don’t understand.

Also, I think it is arguable that this universe is very bad at sustaining life, otherwise it wouldn’t have trillions of cubic light years of nothing at close to absolute zero. Attributing any significance to the fact that, in that unimaginable cold vastness, an infinitesimal smudge of matter has some sort of properties that are interesting to it seems like the ultimate in hubris. The universe is, at best, extremely coarsely tuned for life.

Third, and a related point, the logic of fine tuning seems to be that if something that seems extremely improbable exists, then one needs a cosmic explanation for it. Thus, I would argue that however finely tuned the universe is for life in general, it is far more finely tuned to produce me — with extremely tiny changes to the universe (such as my parents not meeting), I would not be here. My existence is far less probable than the existence of life itself (by the sheer math). Ergo, the only explanation is that the universe is the way that it is to produce me, or, alternatively, that there are an infinity of universes with Tulses that differ infinitesimally from this Tulse. I think physicists should be producing theories that explain the “Tulse tuning” of the universe.

Of course, if things like comets and stars and planets were conscious, they would also have a case that the universe was fine tuned to produce them, since they would also not exist in practically any of the universes that don’t have life. How do we know that it is fine tuning for life, and not for red giants?

And finally, how do we know that life in some form couldn’t exist in universes with very different physical constants? Sure, it wouldn’t be life “as we know it”, but that’s not the criterion, is it? Perhaps if things had been different a hyperintelligent shade of blue would now be speculating on how sterile a universe would have been if it had clumps of matter and nuclear fusion.
#22 MartinB
November 12, 2008

@David
“the difference between theory and hypothesis is one of size, not one of certainty.”

A theory is a model of some part (or all of) reality that has been proposed and has made predictions that have been confirmed. Until then, it is a hypothesis. Size does not matter in this case – if I propose that all elementary particles are in fact spaceships of very tiny dwarfs, it is an all-encompassing statement (at least concerns all of matter), but surely it is not a theory. (Not even a hypothesis unless I state what this implies with respect to observable facts.)

String “theory” has, so far, only made one testable prediction (that of dimensionality) which seems not to be in agreement with reality. It has no predictive power so far except for that one wrong prediction. Usually we reserve the word “theory” for explanations that have been thoroughly tested and are in agreement with experiment.

@Jason
“I think I did emphasize the fact that the multiverse follows from both string theory and inflationary theory”

To repeat it: No it does not. String theory started with the hope of predicting the values of natural constants. People then realised that this was not possible and that string theory could predict any of a set of at least 10^500 different possibilities for natural constants.

Instead of accepting this as a failure of the theory, they then had the idea that perhaps all these possibilities are somehow realised – the multiverse.

There is nothing in string theory directly predicting the multiverse, it is just a way to deal with the fact that the theory has no predictive power and trying to turn it into a virtue.

I’m not saying that string theory is wrong (how could it be, if it makes no predictions – and it may even some day make predictions that agree with experiments and become a good model of the universe) – but it does not predict the multiverse in the sense that, for example, Maxwell’s equations predict electromagnetic waves.
#23 Blake Stacey
November 12, 2008

String theory started with the hope of predicting the values of natural constants.

Actually, string theory started with people trying to understand the behaviour of high-energy hadron collisions, in which the angular momentum of the bits flying off was found to be proportional to the square of the energy. Models were then proposed which accounted for this by treating each particle as a spinning relativistic string, an idea which survives to the present day, even though early models of nucleonic interactions were subsumed by quantum chromodynamics (QCD). Modern models employ stringiness as an “effective theory” describing the emergent properties of multi-quark systems: a tube of flux connecting two quarks in a meson is basically a string.

But this was a thread for cocktail-party philosophy; we should probably stop before we get to the AdS/CFT correspondence.

There is nothing in string theory directly predicting the multiverse, it is just a way to deal with the fact that the theory has no predictive power and trying to turn it into a virtue.

The multiverse could well have been proposed even if string theory had never been contemplated, as it is a consequence of eternal inflation.
#24 Jim Harrison
November 12, 2008

The expression “fine tuning” makes me imagine God as some guy sitting in front of a big old fashioned radio trying to bring in Abraham, Isaac, and Jacob by twirling a dial. Thing is, the very expression “fine tuning” begs the question since it implies that universes are the sort of thing that can be tuned. What we know, if we do know it, is that certain features about the universe that we care about are related to the values of fundamental constants. That everything would be different if the fine structure constant (or whatever) were different should not be used to imply that the fine structure constant could be different or, crucially, that there is some way in which an intelligent being could make it different.
#25 lylebot
November 12, 2008

The hypothesis of a multiverse explains a lot of data

I think it’s more accurate to say that the hypothesis of a multiverse explains why we observe certain data, but it does not actually explain the data itself. As Tulse says above, how do we know that there aren’t underlying constraints that it make it impossible for things to be any different?
#26 MartinB
November 12, 2008

“The hypothesis of a multiverse explains a lot of data”

To me, this hypothesis is rather equivalent to giving up – we find no theory to predict this universe’s parameters, so we look for an explanation that says we actually can’t.
#27 Blake Stacey
November 12, 2008

About the question of Occam’s Razor and parsimony:

Suppose that you had observed the planets of the solar system (as we’ve been doing since antiquity), and you cook up various hypotheses to explain how these planets and their arrangement came to be, based on the known laws of mechanics. If your simplest hypothesis — the one with the fewest fudge factors, and so forth — predicted that planetary systems would also form around other stars, would Occam’s Razor impel you to reject that hypothesis? The number of postulates in a model — the size or “complexity” of that model — is not the same as the quantity of objects which that model describes!

(This becomes forcefully evident in statistical physics, where we have a few short mathematical statements giving us predictive power for collections of ten-to-the-twenty-third or more atoms.)

Or: suppose you’re a young and curious member of a seafaring tribe, the Amnesians, who had generations ago colonized the widely scattered islands of a great ocean. The islands are too far apart from one another to allow communication or trade, and nobody has any record or memory of where the people of your village came from. You begin to suspect that there is more world, or at least more ocean, than is immediately visible: while standing on the shore and watching the fishing fleet vanish over the horizon, the hulls of the catamarans disappear first, followed by their sails. The shadow on the Moon during an eclipse is circular. Perhaps the Earth, the Moon and the Sun are all spheres. Then, while studying the volcano on your island, you see that the flows of lava spurting out its lava tubes into the sea make new rock. The natural processes of the volcano build up land! If there is only one volcano, there must only be a tiny bit of land, but in all that ocean, what special rule mandates that there be only one volcano. . . .
#28 Blake Stacey
November 12, 2008

The point about the statistical-physics aside was that when trying to solve a problem in the kinetic theory of gases, or some other area where statistical mechanics is employed, parsimony urges us to favour the hypothesis with the fewest assertions fed into it, not the hypothesis which calls for the smallest number of physical entities.

Incidentally, during the past few years, string theory has been used to predict that the ratio of shear viscosity to entropy density in a strongly-coupled matter phase such as a quark-gluon liquid is extraordinarily low, in the neighbourhood of 1/4π, two orders of magnitude less viscous than water. Different systems in this category — quark-gluon liquids, ultracold atoms tuned via Feshbach resonance, etc. — should be expected to deviate from this ideal in different ways, just as different real gases diverge from the ideal gas law according to their own peculiarities. Much mathematics remains to be worked out (why do models with supersymmetry seemingly predict what happens in real-world systems without it? etc.) but getting a completely absurd and totally unexpected result in the real world right has to mean something.
#29 MartinB
November 12, 2008

Blake, although I personally do not like string theory, I agree that your statements have some merit.

The statistical physics argument is nice, but in fact it can be turned around: So since we cannot predict which of the 10^10^whatever possible paths in phase space a gas will follow, would it be sensible to say: O.k., but since I believe statistical physics to be the fundamental theory, I predict a multiverse of 10^10^whatever gas universes, each with a different path? Or wouldn’t we rather try to find the fundamental laws behind it all?

My main point, however, is that I strongly dislike people claiming that string theory predicts the multiverse and saying that this is a virtue of string theory – I tried to explain why it is the otehr way round. String theory may still be correct, though.

I was not aware of that new result on shear viscosity, is this really a quantitative prediction or is it just an idea so far? If it is a prediction, how accurate is it?
#30 AnswersInGenitals
November 12, 2008

After almost sixty years as a fervent evolutionist, the Fine Tuning argument has finally compelled me to believe there must be a purposeful, goal directed intelligent designer at the root of life’s complexity. Nothing can ever convince me that a mostly random, purposeless process like evolution could ever produce humans with exactly the correct number of fingers to fit into a pair of gloves!
#31 Blake Stacey
November 12, 2008

The multiverse produced by eternal inflation — which, again, would have been deduced from a model of eternal inflation had nuclear interactions never motivated people to study string theory — does not necessarily include all 10^500 (or however many) possible string theory vacua. I’m hardly an expert in the subject, but to the best of my knowledge, it’s possible that eternal inflation might only generate regions of spacetime which look like de Sitter universes, for example, while the set of all vacua would include anti-de Sitter universes with opposite spacetime curvature.

Careless equivocation between the set of string theory vacua and the multiverse predicted by eternal inflation is sure to be counterproductive.

The statistical physics argument is nice, but in fact it can be turned around: So since we cannot predict which of the 10^10^whatever possible paths in phase space a gas will follow, would it be sensible to say: O.k., but since I believe statistical physics to be the fundamental theory, I predict a multiverse of 10^10^whatever gas universes, each with a different path?

People who lend credence to the many-world interpretation of quantum mechanics wouldn’t have a problem with that. As the saying goes, it’s cheap on postulates, but expensive on universes.

But anyway, I don’t think we’d say that, because in statistical mechanics, we find equivalence classes of points or trajectories in phase space: the specific trajectory which a system follows doesn’t matter. Instead, we care about how many equivalent outcomes there are — typically, how many microstates are consistent with some macroscopic condition.

Again, the multiverse was not proposed simply because a theory people liked admitted many possible solutions, but because a close study of the process by which our Universe developed seemed to imply that the same process would give rise to other regions of spacetime which also resemble Universes.

I was not aware of that new result on shear viscosity, is this really a quantitative prediction or is it just an idea so far? If it is a prediction, how accurate is it?

It’s an exact prediction of a model based on gauge/gravity duality, which gives a numerical result; comparisons to different physical phenomena work out pretty well, particularly given that each real phenomenon is sure to differ from the idealization in some respect. For a fairly recent presentation with oodles of details, see Rajagopal (2008).
#32 Blake Stacey
November 12, 2008

Oh, and don’t forget string/brane gas cosmology: plausible though as yet not fully explored mechanisms exist for bringing the effective dimensionality of a string theory down to a nice and happy 3 spatial axes.
#33 jj
November 12, 2008

“In the beginning the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move.”
-Douglas Adams
#34 cwfong
November 12, 2008

Perhaps it’s time to point out that life fine-tuned itself to fit with this particular universe instead of resulting from a tuning that in effect predicted its particular creation.
Otherwise we are like children accusing our parents of having planned our particular natures and thus responsible for our relative defectiveness.
#35 Louis Savain
November 12, 2008

How can there be more than one universe since the universe is made of nothing? An ex-nihilo universe is the only ontology of substance that does not lead to an infinite regress. Why? Because if the universe is made of things, what are those things made of? And those things are made of other things, what are those other things made of, ad infinitum?

Conclusion, the universe is made of nothing and there is only one universe because there is only one nothing. As simple as that. Sorry.
#36 cwfong
November 12, 2008

But what about the wisest man in the world, who, when asked why he had a stalk of celery jammed in his ear, replied, “Everything gotta be someplace!”
#37 Rickr0ll
November 12, 2008

Louis, strings are the final stage of building blocks of matter and spaecetime. What are you smoking? Besides, information itself is subsatnive and does not lead to infinite regress. God himself has infifnite regress because he has an infinite amount of himself (which is also infifnite) being that god is thus, a multiverse theory still makes sense, becasue one would be too boring.
Oh and ontological arguments are bullshit
#38 Blake Stacey
November 13, 2008

And those things are made of other things, what are those other things made of, ad infinitum?

Nougat. Creamy nougat.

(I’ve already written a damn book in this comment thread, and I’ll be stepping away from the blogohedron until next week, so I won’t be around to continue any discussions here. It’s been great fun, though! Ciao.)
#39 island
November 13, 2008

Wow, what a copout on science, first principles, causality, and just about everything else that can be relevantly listed.

Not to mention much convenient ignorance of the facts:

http://dorigo.wordpress.com/2008/06/23/guest-post-rick-ryals-the-anthropic-principle/
#40 Collin Brendemuehl
November 13, 2008

David Marjanovi?,
The difference between the hypothesis and theory is significant.
The hypothesis asks “What” or “Is” or other suitable question.
The theory is the structure employed to (attempt to) answer the question.

I will also contend that there is at least as much substantive material for the existence of God as there is for multiple universes. “If there can be multiverses there must be multiverses” sounds like the conslusion drawn from Anselm’s argumeht, that “if there can be a God then there must be a God.”
It’s is amazing how little progress mankind has made in th epast 800 years.

Enjoy
#41 island
November 13, 2008

Better yet, Collin… If I were a creationist, (which I am not), then I’d put Lenny Susskind and Richard Dawkins on the witness stand and laugh in their face for thinking that an unobservable multiverse is more plausible than exactly what it looks like:

Leonard Susskind very clearly expressed rationale for this in his interview with New Scientist concerning his new book, The Cosmic Landscape: String theory and the illusion of intelligent design.

Amanda Gefter of New Scientist asked:
If we do not accept the landscape idea are we stuck with intelligent design?

Leonard Susskind:
I doubt that physicists will see it that way. If, for some unforeseen reason, the landscape turns out to be inconsistent – maybe for mathematical reasons, or because it disagrees with observation – I am pretty sure that physicists will go on searching for natural explanations of the world. But I have to say that if that happens, as things stand now we will be in a very awkward position. Without any explanation of nature’s fine-tunings we will be hard pressed to answer the ID critics.

Apparently Lenny doesn’t know the difference between naturally guided evolution and intelligent design either, but at least he is gutsie’ enough to admit that there really is a valid scientific interpretation of the evidence that indicates that we are not here by accident. Few will even honestly ask the obvious question about what good reason might exist for why the implied specialness might be true if you can’t lose the rationale for “fine-tuning” in an infinite sea of possible universes?

Lenny said elsewhere that: ‘The “appearance” of design is undeniable…’ and Richard Dawkins has said the same thing many times, so IF IT WAS a choice between a multiverse and god, then there is more evidence for god than there ever will be for some unprovable and theoretically speculative multiverse.

Once I’d legally established that IDists have a point, then people like Blake Stacy would be forced to quit playing their little game of willful ignorance and denial, and instead find the real reason that that the universe is observed to be strongly constrained by an biocentric cosmological principle.

Course, and complete theory of quantum gravity would justify the multiverse, but a COMPLETE theory isn’t the same as the bogus hype and lame rationale that you get from neodarwinians and the cutting-edge of theoretical physics.
#42 Collin Brendemuehl
November 13, 2008

A good starting point is mainstream thought.
One does not have to be a 6-day/6ky “creationist” to accept some for of creation. Yockey wants a creator for & before the Big Bang.
Right now the only difference I see is the *when* of creation. Even some evolutionists have given in to a degree.
#43 cwfong
November 13, 2008

Collin noted this:
“If there can be multiverses there must be multiverses” sounds like the conslusion drawn from Anselm’s argumeht, that “if there can be a God then there must be a God.”

How about, if there can’t be a God, then there must not be one?

Or if there are multiverses, we can only guess at their construction – so can we only guess at their constructor?

Ad infinitum?
#44 Tulse
November 13, 2008

Even some evolutionists have given in to a degree.

What does biology have to do with cosmology?
#45 cwfong
November 13, 2008

What does biology have to do with cosmology?
Well, without cosmic rays (cosmic particles) there would likely be no biology.

Oops, I may just have given creationiss another tool to misuse!
#46 Collin Brendemuehl
November 13, 2008

island,
One of the greatest of all quasi-scientific oxymorons: “naturally guided”

cwfong,
Study the arguments and note the similar conclusions.
Do more than just read blogs.

Tulse,
Apparently some scientists believe in inter-disciplinary relationships. Don’t know where they got that silly notion.
#47 Chris
November 13, 2008

I found this post and the article it relates to pretty interesting.

However, throughout my reading of both I was dogged by what seemed to be to be an elephant in the room that neither this blog post nor the original article addressed. I can best sum up my concern as: we seem to think we know much more than we do.

To me this was best illustrated in the footnote at the end of the article. The note lists the impressively small changes to the fundamental laws of physics that would render this cosmos unfit for life. To me, these were obvious to the point of being uninteresting. Surely, it’s not interesting to suggest that creatures evolved in this cosmos, under our observed laws of physics, wouldn’t survive under different physical laws.

Yet we notice this and wonder to ourselves how lucky we are to live in this universe.

What if the laws were different? Fundamentally different, in every way. Life has only existed in this universe for a fraction of the time the universe has existed. It may only exist for a fraction more. While a 13-odd billion year old universe with fundamentally different laws would not produce the life that we know, or even life that we could imagine, it’s not to say that for a different-sized fraction in a different stage of existence, in a way we would be fundamentally incapable of understanding, life wouldn’t exist and flourish for a fraction as large or larger of that universes existence.

I’ve long believed the anthropic principle rested on a bedrock of yet-to-be discovered explanations for the fundamental parameters we have. When it comes to the fundamental laws of physics, we all seem creationists. We take them as given, set for ever, or at least as far back as we can see.

Surely, this is like biology before Darwin. Let’s not miss the lesson of Darwin: just because we’ve yet to discover the how, doesn’t mean it isn’t there. It certainly doesn’t require a new “creation fable” admittedly untestable and unobservable, except by eliminating very alternative.

To me, Occam’s razor points to the laws of physics as they are not because they have always been that way, but because some process that is fundamentally rational and physical, though perhaps not as we currently understand it, left them this way.

To hypothesize additional universes to solve a problem which may plausibly be solved by a closer look into the early moments of our universe seems the fanciful realm of theology, not the rational one of science.

But the dreaming sure is fun.
#48 cwfong
November 13, 2008

Collin: Do more than just base the certainty of faith on the uncertainty of those who lack it.
It may not be an either/or proposition.

Or did I hear you say something about “similar conclusions” being more than a probability assessment?

And actually the reading of blogs leads to the discovery of both old and new research that of course can also lead to the birth of new bloggery, but hell, nobody’s perfect – perhaps not even that great blue blogger in the sky.
#49 Rickr0ll
November 13, 2008

i have to agree that the only life we know of is us, so the universe being “primed for life” seems excruciatingly ad hoc. We don’t even know if the paramenters can be changed in the first place, like jim harrison said. in addition, we only have 4 fundamental forces, and only deal with 2 substances in science: spacetime and energy/matter. any discussion about alternate realities ought to preclude that there are operating forces and entities which are utterly beyond our ken. Sticking to the type of universe we have now and saying, “well if it were something like this…” seems dubious. and indeed, our universe could have been even better primed for life if anyone had given it serious thought. we are essentially alone in the universe, which is highly suspect if you assume the anthropic principle.
Tulse, you were right, and i’m sorry for copying you.
#50 Collin Brendemuehl
November 13, 2008

The certainty of faith is relational and propositional. The certainty of knowledge has different warrant.

The “similar conclusions” seem to stem from similar argumentation structures. Logic in argumentation has changed little in the past few thousand years.
#51 Rickr0ll
November 14, 2008

“logic in argumentation has changesl ittle in the past few thoudand years” What about the dialectical method, what about empiricism and the larger framework of positivism. Ontological methods have some and gone already, and disciplines, as such, weren’t really introduced until socrates. what about mathmatical rigor in general, one of the core foundations of argumentation today? quit sounding so profound and come back to the world of the living collin.
#52 cwfong
November 14, 2008

Collin says: “The certainty of faith is relational and propositional. The certainty of knowledge has different warrant.”

Where does that leave the certain knowledge of and about your creator God? A matter of relatively reliable probability?
#53 Rickr0ll
November 14, 2008

in a ,multiverse, gods may very well exist. in addition to sentient beings that became godlike. However, i am probly making an unnecessary distiction between the mega-aliens and dieties. Read The Intelligent Universe by James Gardner.
#54 cwfong
November 14, 2008

Undoubtedly earth creatures aren’t the only purposive calculative entities in the universe, not to mention in a proposed multiverse. But the book just cited does little to convince us that any are omniscient or especially omnipotent. Without which qualifications our local Gods need not apply
#55 RickrOll
November 16, 2008

the short answer is that i agree cwfong, but if you are interested to see my logic (if indeed that is what it is), read on…

omnipotence has this very annoying habit of interfering with itself. You know excacly what you are goiing to do before you do it. and you can never change your mind, even if you are wrong. After all, True omnipotence i feel is analgous to the “unfiltered perception” concept in Mostly Harmless. It deals with altering the very nature of reality, or rather, allows one to summon the exact thing you want by making whatever it is you want 100% probable, by merely observing said reality. The only way to properly do this is to be omniscient. But what if you were to change your mind? Whoops, you can’t; so omnipotence in a way, enslaves whomever is unfortuante to be bestowed with it. you really have no power at all except to let reality unfold, and you would be as natural a part of it as anything else.
Personally i feel omnipotence to be a relative thing, for a god may have utter control over your destiny, but he may not be able to interfere or even notice other universes. If we can’t travel between those universes, then the distincion between local and actual falls away. And that, luckily enough, brings my argument back to the beggining. It is self defeating. The only real role of any sufficiently powerful being would be the creation of completely free universes apart from its control. And it need not do so anyway, because universes would arise naturally. If the distinction of god/not god dissapears as well, then it is best to say they don’t exist, as Occam states. Believing in a being with infinite power is a great difference from a unimaginably vast but finite multiverse. The rare universes that fall into those rare temporal geometries and repaet themselves would extend the spacetime of the mutiverse to infinity (assuming such special universes don’t decay…)
#56 cwfong
November 16, 2008

Rickr0ll |,
I agree that an omnipotent and necessarily omniscient being would have to be almost a purposeless automaton, begging the question of how that being’s existence could have been for the purpose it was destined to carry out. But omniscience by definition can’t be relative. And can a less than omnipotent/omniscient intelligence be more than a pretender where the status of God is both an aspiration and a requirement?
The best I can offer as to the role of intelligence in the cosmos is the supposition that the more sophisticated the consequences appear, the less they were the result of directed purpose.
#57 Juanito Crandello
November 16, 2008

But then who was it who finally said (a few centuries ago): “There cannot be two infinities.”

Or more, I would add.

Someone cited above observes that we are coming to the end of what can be observed.

From where we are located and with the degree of our present understanding, I would add.

Until humans can come to understand the mechanics of where matter ends and (theoretical) anti-matter begins, perhaps we can hold off on all of this theorizing, this mental masturbation, this other form of escapism. Where is the light of stars that has not yet reached us? Will not reach us for another billion years? From where will it come? They say that the nighttime sky would be white if the universe were boundless. Yet there is all of the light which yet remains, is bound towards us. If the universe is boundless, there would be so much light that could never reach this planet. Never, no matter how many more billion years of time and distance yet to travel. It never began and it will never end.

Multiverse? Yes, of course: how large or small would one of these things be? Did Carl Sagan have an ass? Assuming that he did, then every time that he took a crap, that pile of crap might have been just another universe.
#58 cwfong
November 16, 2008

You were doing OK until you ended with that pile of crap – which by definition is a pile of crap. Or are you extolling the possible benefits of talking out of your ass?
#59 JonF
November 16, 2008

There is not an infinite or even near-infinite number of universes. The number is fairly large, but quite limited. The reason for this is that nearly all possible universes are canceled out by interference with other possible universes (basic wave mechanics) leaving only a relative handful that can actually come into being.
#60 cwfong
November 16, 2008

I suppose that anything less than infinite would be a relative handful comparatively. And a hypothesis that basic wave mechanics guarantees a continuous expansion of the multiversal population would arguably make as much sense as the one just posited.
#61 Garyoke
November 16, 2008

And yet…and yet…

it’s all so finely tuned….I’ve always considered myself quite panthesitic…..quite agnostic….reading this article give me pause……
#62 cwfong
November 16, 2008

But was not the 5th symphony the result of accidental noodling?
#63 RickrOll
November 17, 2008

i guess now we are at an impass cwfong, because even omnipotence might fail at places where there is no logical formulation of concept (what does the interior of a black hole look like, for example- which may yet also lead to the conclusion that gods are exclusive to the spacetime that comprises their respective universe), and i was referring to the 0/infinity scenario, it is either one or the other. I must confess, that if you can’t observe multiverses, then the notion of “relative” is very shaky. i guess it would mean relative to those hypothetical observers, wouldn’t it? After all, god’s omniscience is from our perspective zero. Which is impressive really, because even we cannot fathom Nothingness lol.”And can a less than omnipotent/omniscient intelligence be more than a pretender where the status of God is both an aspiration and a requirement?” i love that, i may have to quote you on that, it’s quite good; yet, human beings themselves are pretending to be human, it’s how we learn to socialize, how we become acculterated (thanks to those lovely mirror neurons!). It is arguable that anything that would be defined as “human” (a terribly vauge term that may of may not be exteneded to such entities as Cro-magnon man and/or Neanderthalls, much less other sentient life froms) goes through this process as well. Pretending is a necessary part of the definition, much like consciousness implies being aware of your own awareness. Humans are terribly fond of the label of “Pariah” and “Untouchable”, and only amongst ourselves can this distinction be made. To fathom humanity is to be human, and to fathom infinity/0 is to not fathom it at all. JonF, all finite numbers are the same distance from infinity lol. Does the population U (i’m sure you guys can guess) really increase? Neat!
Oh, does anyone have a helpful remark about the Flatness of the Universe, because it’s very tricky to understand
#64 John Lehman
November 17, 2008

A very interesting observation and thought by Linde at the end of Tim Folger’s Discover article:

As for Linde, he is especially interested in the mystery of consciousness and has speculated that consciousness may be a fundamental component of the universe, much like space and time. He wonders whether the physical universe, its laws, and conscious observers might form an integrated whole. A complete description of reality, he says, could require all three of those components, which he posits emerged simultaneously. �Without someone observing the universe,� he says, �the universe is actually dead.�

This “mystery of consciousness” seems to be more in the line of the Aryan religious traditions (Hinduism, Buddhism and Zoroastrianism) then the Abrahamic, Semitic traditions ( Judaism, Christianity and Islam) though they each are guilty of making decadent intellectual constructs (idols) of “God”, “maybe God” or “non-God” and then arguing and killing each other for their respective constructs (idols).

Meanwhile this “mystery of consciousness”, of being, of the universe or what ever name is acceptable to the current intelligentsia, continues to inspire, motivate and fill with wonder and awe all truly creative souls. Leading those souls, as they have done throughout all of history, to great discoveries in all the sciences and arts and a marching forward of human civilization. Yes with out “it”, this “mystery of consciousness”, as Linde says, “the universe is actually dead.”
#65 Scott Hatfield, OM
November 17, 2008

Jason: I am still interested in hearing an explanation of how postulating additional dimensions or universes without experimental support is not a multiplication of entities. Surely Occam’s little piece of advice is not confined to entities such as ‘Big Sky Daddy.’ For example, Wikipedia remarks: An entity is something that has a distinct, separate existence, though it need not be a material existence. In particular, abstractions and legal fictions are usually regarded as entities. In general, there is also no presumption that an entity is animate. Care to comment?

Blake:

I always enjoy your thoughts. If I understand you correctly, you are arguing via your ‘volcano in the ocean’ example that inductive reasoning can be used to justify the possibility of other (unknown) volcanoes in the(known) ocean. Hey, I’m a Darwin fan and thus a big fan of coupling inductive reasoning with deduction. My question, though, is this: in your example, is the multiverse a volcano, or is it an ocean? Could your example be used to justify a completely other ocean unconnected to the known ocean? If so, what would you base that justification on?

JonF:

There is not an infinite or even near-infinite number of universes. The number is fairly large, but quite limited. The reason for this is that nearly all possible universes are canceled out by interference with other possible universes (basic wave mechanics) leaving only a relative handful that can actually come into being.

If true, then the claims of the ‘fine tuning’ crowd merely regress to the relatively small set of realizable universes, and the question as to why some of those universes permit life is still an interesting question.

Cwfong:

But was not the 5th symphony the result of accidental noodling?

As someone who holds a degree in music composition, let me assure you that the answer is ‘no’. All musicians ‘noodle’ from time to time. It is what you do with your fragments of musical material that form the basis of the compositional process. There is very little that is ‘accidental’ about the imposition of long-scale formal design found in Beethoven. There seems to be something problematic about any analogy between human creative activity and the inference of design in nature.
#66 cwfong
November 17, 2008

Scott:
The analogy would be that both life and music can have started by accident, yet have been fine tuned by an intelligence that had not intended that accident. The analogy concerns the accident, but not necessarily the source of the intelligence. Although Beethoven did fashion those initial notes into one of the greatest of man’s creations, and others like him have contributed to human evolution over the millennia.
#67 386sx
November 17, 2008

But was not the 5th symphony the result of accidental noodling?

Sure sounds like it. He should have spent a little more time on it! Just kidding. (Not!)

I like F�r Elise a lot though. (Except for the really lame part in the middle.)
#68 Scott Hatfield, OM
November 17, 2008

Cwfong:

Thanks for the clarification, but I’m still in the dark as to what you mean by a shaping ‘intelligence.’ Is the ‘intelligence’ that shaped the original accident an outcome of the whole process (in other words, something like sexual selection) or is it something like the ‘entities’ to which Occam’s Razor is supposedly addressed? That is, does the ‘intelligence’ have a real, independent existence from the evolutionary process? If so, it sounds to me as if you are describing something like Big Sky Daddy. Puzzled…SH
#69 cwfong
November 17, 2008

Scott:
Intelligence, if you define it as the ability to acquire and apply knowledge and skills, has been part of the evolutionary process almost from the beginning, but if it shaped the original accident of life’s creation on earth in any way, it would almost surely not have been because of some celestial entity’s specific intent or direction.
But with regard to humans specifically, an example of how intelligence of early humans, or at least their immediate ancestors, has shaped our evolution would be the acquisition of the skills required for the use of tools. Which I’m sure I don’t have to explain to you, but mention it only as an example of what I had been referring to earlier. Evolutionary psychology has a lot to say about this aspect of evolution- much of it being BS in the view of neurobiologists like Steven Rose, but arguably not all of it.
#70 RickrOll
November 18, 2008

James Gardner comes up with a nearly identical idea in his work Biocosm. Having read the second book on this subject, The Intelligent Universe, i see that he wasn’t the first voice on the Integral Consciousness aspect. It is an interesting idea, but what function does Heisenburg uncertainty play? in a panpsychist reality, the quantum uncertainty becomes somewhat of an embarressment of riches. right? not that i don’t appreciate panpsychism, i am an adherant myself, but it is really more of an opinion. I don’t even see a formulated hypothosis of it really. But the biggest thing is that intelligent Agents are the ones that cause the proliferation of habitable universes.
#71 cwfong
November 18, 2008

RickrOll
Humans are intelligent entities who have acted in purposeful ways to change the course of the nature that surrounds them, except that the results are never exactly as intended. And I suspect that the bulk of the consequences of any purposive acts anywhere in the cosmos have been largely unintended and unanticipated. So one could say we have a somewhat paradoxical situation at best, where purpose may contribute, as you posit, to proliferation of a habitable universe, but if so, through a largely accidental process.

Works like Biocom seem largely the product of hope rather than cold appraisal.
#72 jo5ef
November 19, 2008

Jason its not often that i disagree with you, but on this one i’m on the side of all those above who take issue with both god and multiverses. They both seem to be concepts that have no real evidence to support them, postulated to explain the gaps in our understanding of observable phenomena.
You don’t need multiverses to contradict fine tuning arguments, as pointed out above.
I’m no astrophsyscist but I think a skeptical position on strings, branes and multiverses is the default until some testable hypotheses are produced.
#73 Toby
November 19, 2008

In any other paralell universe the same or simmular laws apply. exg. gravity, light, time. the same type of life should also apply. if that is true the same dna makeup, and atom structure should apply. in order to find these other parallel universes we need to find the math that makes up everthing in this universe. one formula that is the answer to all. i don’t think running molicules into eachother and chasing them is the answer.
#74 RickrOll
November 24, 2008

toby. that just doesn’t make sense.
Indeed, cwfong, you aren’t wrong in this. Like i said, i want to believe that it is the truth, but, as per the idea, it is hard if not impossible to falsisfy. however, i do have a link in regards to CTC’s, that is, Closed Timelike Loops, which would, if they exist as universes under the ideaology of eternal inflation, would be all that is necessary to continue the existance of the multiverse indefinatelly. http://en.wikipedia.org/wiki/Closed_timelike_curve

http://www.citebase.org/fulltext?format=application%2Fpdf&identifier=oai%3AarXiv.org%3Aastro-ph%2F9712344.

I know. terrible. oh well, a links a link.
#75 cwfong
November 24, 2008

RickrOll:
Simply put, time as a dimension is a measure of relative rates of change. When you start seeing it as a tangible entity in the cosmos, that’s where the trouble starts. The putative multiverse will continue indefinitely until all movement stops, at which point there would be an end to the time that had been taking its measure.
But existence cannot disappear into nothingness any more than your CTCcs can help account for its beginning. Something did not come from nothing. There has always been something.
If time had a beginning, it was when that something started to move or change, but then there’s the old problem of where the potential for such change came from without a prime mover, if you will.
Which there either always was as well, or again something will have sprung from nothing. Which simply did not happen.
#76 RickrOll
November 24, 2008

Time IS a tangible entity, which is why it is warped and distroted in exactly the same manner as space in General Relativity. Indeed, Time itself changes, which leads to the question of “in what way is it changing?” Not in time, unless there are multiple dimentions of time as well. A quantum singularity by its definition does not move or change, and time ends inside black holes and at the beginning of the universe.

Only by putting objects inside a larger framework, which for black holes is a comparitively easy matter, does this work itself out. For the entire universe, the multiverse exists. I fail to understand what you intend to do by stating that you can work backwards from a reality that is cyclic in time and end up in one that is linear.

Besides, i was working forward in the construction of the multiverse, not backwards as far as the evolution of the shape of time has is concerned. YES, time Has a shape. Now if the past was engineered by the future, in what way would we be able to tell? In practise it is nearly impossible to tell such things, but logic assumes that such structures have always existed.

“Something can’t come from nothing.”

Indeed, CTC’ may degenerate, that is perfectly natural, but if there are enough of them, under eternal inflation, there will always be some set of universes that are currently in existance. Even if it only in 1 in 1000 universes where a CTC can be created, either as a fluke of that universe’s geometry or by clever engineering, a CTC would last long enough in time to generate several child universes, many of which will do the same until another CTC is formed. After all, when will our universe end? Will it? current cosmology says no, in which case, another cosmic inflation event seems inevitable.

Besides, what about universes that opperate “Backwards” in time? After all, there is only one indication of time’s arrow, and that is Entropy. In many universes, this arrow is likely to be facing the other direction. The symmetry of time according to physical laws begs scientists to be at least marginally concerned about the future of the universe as much in addition the past. Entropy is different in other universes, after all, barring the possiblilities that our familiar Thermodynamic Laws even apply at all in most cases.

I think cwfong, that you may have been taking a rather anthropomorphised view of this subject matter. But still, i am very interested in your input.
#77 cwfong
November 24, 2008

RickrOll: I would have thought it was you, with your hope of looking for some sign of directed purpose in nature, and a hint of some intelligence in its creation, that were taking the anthropormophised view.

Time as a tangible entity is an illusion, just as emergent properties such as consciousness and “mind” have been inaccurately seen and dealt with as tangibles. Dimensions are descriptive concepts – no more tangible than the mathematical formulas seen by some as a material force in nature.

And while there will always be something out there, there’s no solid reason to believe it will be an unending collection of multiverses. And what I was doing in my previous post was to try to cut to the chase and point out that some of the basic assumptions that your propositions depend on are not, in my view, tenable.

I also understand that too many have too much invested in seeing time as malleable in and of itself, rather than a reflection of that malleability in nature, that my view will have to remain in the minority. Maybe even a minority of one.
#78 cwfong
November 25, 2008

RickrOll – I forgot to remind you that one of the links you cited was to an essay attempting to shed light on how the universe or universes could or might have been created from what was presumably nothingness.

But to arrive at something from nothing is doubtless as difficult to fathom or explain as to do the opposite and arrive at nothing from something.
#79 RickrOll
November 25, 2008

There is a whole chapter on the Shape of time in The Universe In a Nutshell- the Successor to A Breif History of Time. Time may not be Moving, but it is evolving throughout it’s history. Space and time are equal, unless you say that space too, does not bend or curve. Is this what you are saying? That was abandoned fifty years ago when Einstien published his papers, and observations have never proven the contrary. Unless you have a source to site.

I, again, have to agree, not tenable. But logically sound

I look for no directed purpose, except for existance in and of itself. You seem to be refuting that claim. Sure, there was and will always be something, and you have every right to regard the multiverse as dubius (please do!), but with nothing to substitute, the hypothoses, as grandiose as it is, still runs unnopposed.

I will go over my sources, and get back to you.
Oh, and your last statement, it worls well. But what about the Actual Existance of Nothing? No, not a semantic word game, a query: can Nothingness exist without contradicting itself? Nature replies no, and the best example of this is vacuum fluctuations, which, fittingly, look to be the springboard for future Inflation events.

I think that if Nothingness were realized, such an outright logical contradiction is liable to be replaced immediatelly with a reasoned existance, like ours, for example. You don’t have to believe in this at all, this is my own queer slant of things… However, i am compelled by the fact that existance seems to be fundamentally inevitable, one way or another, throughout all eternity.

So a multiverse, in that sense, exists without opposition, though perhaps it would be more like a Proto-universe instead. No matter what the case may be, Nothing is never an answer. 0 is always an approximation, and infinity is unrealistic. now imagine what that means for my 0/infinity comments above if you really want to screw your noodle lol.
#80 cwfong
November 25, 2008

Oh, and as to which direction your imaginary arrows of time might point in any theoretically diverse universe, it says little about the creation of any universe in a cosmos that always was and always will be no matter which way the arrow points.

Two beams of light may pass each other in opposite directions, but neither will be able to reverse that exact process. Their respective “times” will have gone in the same direction, regardless of the beam trajectories. I expect the same will apply to any multi change directional multiverses.
#81 cwfong
November 25, 2008

My last comment crossed yours in the same moment of time. You misunderstood if you feel I regard the multiverse as dubious. It’s some of the cited conceptions that I find suspect. And space’s bends and curves are dimensional, just as is time – they are descriptive, not entities in and of themselves. A curve is not an entity separate from the material or force that it describes. Neither is time.
And I didn’t say or imply that a nothingness might exist. The point was that it doesn’t and never could have.
#82 cwfong
November 25, 2008

It occurs to me that the use of time as a metaphor may have contributed to a belief in its evolution – where again it is the use of that metaphor that has evolved. And a metaphor is not a tangible entity.
#83 RickrOll
November 25, 2008

what about gravitational lensing, cwfong?

“Two beams of light may pass each other in opposite directions, but neither will be able to reverse that exact process. Their respective “times” will have gone in the same direction, regardless of the beam trajectories. I expect the same will apply to any multi change directional multiverses.” ????? Thier respective times? Photons are timeless. The metaphor of time has evolved, huh? no the metaphor is that the universe has a “lifespan”, thus “evolves” is part of the metaphor. The metaphor isn’t any different.

By the way, if those photons were travelling backwrads in time respective to one another, they would appear to be chasing each other, not passing. as soon at the photons are emitted, they would have been a set distance from one another, as they would appear to be going the same dierction. like a tennis serve. One is forward the same time a serve from the opposite end of the court is going backward.
#84 cwfong
November 25, 2008

RickrOll
I’m trying to make a point about your “arrow of time” conceptions and you turn it into a physics problem. And then you posit what photons would do if traveling backwards in time, not understanding why in reality nothing travels backwards in time.

In fact you seem to have been making my point – that photons passing each other could not in fact have been going in opposite directions time-wise.

As to metaphors of and/or for time, check this out:
http://changingminds.org/techniques/language/metaphor/metaphor_time.htm

In any case we’re never going to agree or even be on common ground as long as you see time as a property of nature and I see it as an abstraction in the “mind” of a calculative apparatus.
#85 RickrOll
November 25, 2008

cwfong, there sure wasn’t any scientific approach to the concept of time in that link. It uses everyday human conceptions of time, combined with figurative speech, to make it’s points. I’m afraid i cannot see the relavance. The ehole concept of extra dimentions is very closely tied up with the fact that they have a very specific shape, calibi-yau spaces (sp?), as they are constantly referred.

Measurements of time are very different from time itself. Time is a dimention just like space.

The Arrow of time IS a physics problem. No, photons occupying the same universe couldn’t be going backwards in time, and i would very much appreciate it if you would take the time to look into this in Briane Greene’s The Elegant Universe, and/or The Fabric of Spacetime. I’m sorry cwfong, i have to side with the physiscists on this one.
#86 cwfong
November 25, 2008

You can side with the physicists, as can I, but it would help if you really understood the concepts involved.

And photons in any universe in the overall cosmos (for want of a better word) would not be going backwards in time there either, whether it’s time as you think physicists see it or time as philosophers see it.

I know a lot more about physics than you might think, and you may know a lot less about it than you feel the reading of these cited tomes has taught you.

This is even more obvious from your reaction to the link I gave you, which relates to science much more closely than you can accept. Your misunderstanding about how science uses time as metaphor is something that would become clear, should you do more research on that very topic.
#87 cwfong
November 25, 2008

I like this site, for example, and this item in particular:

http://www.informaworld.com/smpp/content~content=a789149289~db=all~order=page
#88 cwfong
November 26, 2008

You also might be interested in this discussion, which in some ways parallels what I am thinking could be true, and in other ways what you are hoping is true. (Although there’s much I take some issue with, such as his take on consciousness.)

http://www.salon.com/env/atoms_eden/2008/11/19/stuart_kauffman/
#89 RickrOll
November 27, 2008

photon’s don’t move in time. that’s the real problem with the analogy. They only expend energy in the spacial aspect of spacetime, which was the cornerstone of Special Relativity. And since they have a very distinct amount of energy, that distance can be tracked in time, 186,000 miles a second. photons do not “see” past, present or future.

It is similar to pages in a flipbook cartoon, really. In fact, there is a whole peice on this in The Fabric of Spacetime, where due to relativistic motion, our present coincides with the past and future of different parts of the universe. The tricky bit is when gravity changes things… from what he spoke of, it only changes the shape of the slices, but doesn’t truly alter the basis of the analogy. Of course i understand time’s motion as an analogy, i have no problem with this.

You are talking about the emergance peice correct? I’m afraid i will have to take a better look at your links later. It’s 1 am here. sorry.

You still evaded the question in regards to the very specific notion of the shape of spacetime, which, from the perspective of string theory, particularly that of inflation, that different dimentions have expanded while others have remained small. Time is one such dimention. Every time Green makes a point of giving space and time equal merit, as they are, from relativistic perposes, exactly the same. Is space a metaphor as well? let’s get back to that, for i feel that i’m losing you here…
#90 cwfong
November 27, 2008

The dimensions change but the “expansion” is in the items they were meant to measure. But at least you are recognizing time as a dimension and not a tangible entity or even an inherent quality of such an entity. Let me try this on you: Any construct that is defined in part by the nature of its movement will have time as a dimension.
So when you refer to dimensions expanding while others remain small, the significance is usually that a variance is occurring contrary to expectations formed earlier. Time slowing down is a metaphor for a change in the expectations of how that entity or formation was expected to move.
Try not to quibble with the following which is meant only as an illustration: The movement that is described by the measurable time it takes to get from here to there, such as we have determined the speed of light, and which has also appeared to be a constant, comes to be an expectation to the degree that it ends up being designated essential to the laws of nature. Another such expectation has come to be called the law of gravity. And we find that gravity in certain conditions can change the direction of light temporarily, altering the time it was expected to take between the aforementioned here and there. (Whether any photons “moved in time” or not is irrelevant to this demonstration.)
Was the speed altered? Not necessarily. But the appearance in this scenario is that time was slowed down, because the route taken by the light was slightly off.
The metaphor that has been applied is that time slowed down. But time didn’t slow down, whatever the reason that the light took longer to arrive. Time is not in reality a quality of the light, or even a qualia, but it has become part of our language to refer to it as such. Just perhaps as we refer to beauty as a quality of an object when in actuality its a manipulated abstraction in the mind’s eye of the beholder.
Is space a metaphor? It’s a metaphorical concept certainly.
“String” theory is a metaphorical construct that proves out because of its accuracy in predicting future events. So is the shape of space time, which we have attempted to describe again in the form of a metaphorical abstraction.
And you stated: “The Fabric of Spacetime, where due to relativistic motion, our present coincides with the past and future of different parts of the universe.” That’s almost a meaningless statement unless you try to give it some metaphorical inference. The present by definition only coincides with another present, even if, as the old joke goes, you can’t get there from here.
#91 cwfong
November 27, 2008

Here is an interesting version of a time slowing scenario consistent with what I wrote above when it’s evident from the composition that I should have been sleeping.
http://www.perimeterinstitute.ca/en/Outreach/Explore_Our_Universe/Why_Does_Gravity_Slow_Time?/
Note that the writer assumes we understand that time is used as a descriptive metaphor because it’s defined in part by comparison of the disparate feelings of the two people in the illustration. Note also that while time appears to be slower in one place relative to the other, the two people are sharing the same “present” when they communicate. Which shows, in effect, that the time anywhere is always now.
#92 quasarpulse
November 30, 2008

I had much the same take on the beginning of this article, but to me it actually seemed to get worse from there. While the quotes from scientists were interesting, the analysis in the article, I thought, was absolutely awful.

http://evenmoregrumbinescience.blogspot.com/2008/11/bad-science-and-bad-logic.html
#93 zenithcollector
December 28, 2008

we’ll i am no scientist, physicist etc. I am a writer, a fantasy writer. I have studied different religions and i studied some facts about multiverse theory. There is some evidence i know. Studying some religions and being open to some ideas about the creation, almost make me an atheist. If Multiverse explains some theories then maybe it is possible, cause it’s no impossible.
if some one ask if there is a God, the answer is a question “how and why”… you can start at that
#94 Dann
January 13, 2009

I’m quite ignorant on the subject, but the idea of multiverse is not very appealing to me. A somewhat interesting oddity that annoys me is similar to that thing pointed by someone, I think it was either JBS Haldane or Bertrand Russell, that everything would repeat itself infinitely, and almost all the sorts of crazy stuff would exist. Even Tolkien’s “lord of the rings” or something very close to it would be real history in some universe, as long as the story does not imply something that is impossible in all the infinite universes. Unicorns, faeries, gnomes, goblins, ghosts… all these creatures would exist… and why not some god that could come as closely as possible to ominpotent (meaning, superpowerful to the extent being almost hindered only by logical impossibilities)…

The best answer to the fine-tuning argument is that the universe simply isn’t tuned for humans, beetles or life in general. 99,99% of the universe is not suitable for life, much less human. Mark Twain compared the idea of a universe made for humans to the notion that the Eiffel tower’s purpose is to support the thin paint layer that cover the knob at the top.

But if science really suggests that multiverses do exist, so be it. Does not matter how weird it is.
#95 D_E_R_M_A_N
March 14, 2009

Thank youu
#96 Fitness
March 16, 2009

if some one ask if there is a God, the answer is a question “how and why”… Always an alternative is required.
#97 theme
May 9, 2009

good article and nice answers.ı like this area : )
#98 lidaseo
May 9, 2009

thank for knowing.
#99 film izle
May 20, 2009

if some one ask if there is a God, the answer is a question “how and why”… Always an alternative is required.
#100 sözler
May 21, 2009

Sam, the question is how do you know that any one commenter is a certain nationality? With the double “aa” in his name tumaat could just as well be Dutch. Declaring all the persons in the third largest country by population with one single attribute is not very bright either.
#101 sevişmeler
May 21, 2009

They also sound like people who are in no condition to be credible credit risks.

In principle I would agree with this statement. The problem is that for most of the last ten years the banks did not agree. They were eager to get people signed up for the debt treadmill precisely because the interest rates and fees were so profitable for the banks. They never considered what would happen when a large fraction of their borrowers became unable to roll over their debt (the ability of so many borrowers to temporarily cover the credit card bills from the HELOC ATM helped postpone this day of reckoning).
#102 sohbet
June 6, 2009

The best answer to the fine-tuning argument is that the universe simply isn’t tuned for humans, beetles or life in general. 99,99% of the universe is not suitable for life, much less human. Mark Twain compared the idea of a universe made for humans to the notion that the Eiffel tower’s purpose is to support the thin paint layer that cover the knob at the top.
#103 sezgin
June 8, 2009

Twilightturk yeni yüzüyle karsınızda..

http://www.twilightturk.com
#104 sohbet
July 5, 2009

It occurs to me that the use of time as a metaphor may have contributed to a belief in its evolution Sohbet- where again it is the use of that metaphor that has evolved. And a metaphor is not a tangible entity.
#105 chat
July 5, 2009

In any other paralell universe the same or simmular laws apply. exg. gravity, light, time. the same type of life should also apply. if that is true the same dna makeup, and atom structure should apply. in order to find these other parallel universes we need to find the math that makes up everthing in this universe. one formula that is the answer to all. i don’t think running molicules into eachother and chasing them is the answer.
#106 seslichat
July 7, 2009

we’ll i am no scientist, physicist etc. I am a writer, a fantasy writer. I have studied different religions and i studied some facts about multiverse theory
#107 bilgisayar
July 20, 2009

imza bilgisayar
#108 dış cephe kaplama
July 20, 2009

Great post.Thanks a lot.
#109 twilight
August 1, 2009

twilight
#110 söve
August 5, 2009

Good topic.
#111 New Moon
August 24, 2009

New Moon
#112 wloger
October 12, 2009

thank wloger you.
#113 jono1177
November 5, 2009

why not say that god made the multiverse and the universe because people don’t like god any more.
#114 sohbet odaları
February 25, 2010

thanks
#115 nanayda
July 15, 2010

why not say that god made the multiverse and the universe because people don’t like god any more.thanks

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