Why cosmic inflation's last great prediction may fail (Synopsis)

“The paradigm of physics — with its interplay of data, theory and prediction — is the most powerful in science.” -Geoffrey West

Cosmic inflation, our earliest theory of the Universe and the phenomenon that sets up the Big Bang, didn't just explain a number of puzzles, but made a slew of new predictions for the Universe. In the subsequent 35 years, five of the six have been confirmed, with only primordial gravitational waves left to go.

Image credit: NASA / WMAP science team. Image credit: NASA / WMAP science team.

Inflation predicts that they could be large or small, but based on the simplest classes of models and the measured value of the density fluctuations, the gravitational waves must be within the range of telescopes during the next decade. If we find them, either one of the two simplest models could be correct, but if we don't, then the two simplest classes of models are all wrong, and gravitational waves from inflation may be invisible to us for the foreseeable future.

Image credit: Kamionkowski and Kovetz, to appear in ARAA, 2016, from http://lanl.arxiv.org/abs/1510.06042. Results presented at AAS227. Image credit: Kamionkowski and Kovetz, to appear in ARAA, 2016, from http://lanl.arxiv.org/abs/1510.06042. Results presented at AAS227.

Come learn the science of why and how the last great prediction of cosmic inflation may fail!

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ethan says this was a founding prediction of Big Bang theory

"•there would be a great cosmic web of structure, with small, medium and large-scale structures clumped together in certain patterns,"

Ethan this is completely untrue. The cosmic web and large scale structure was a complete surprise and shock when technological advances began knocking out data in the late 1980's.

this much is actually conventional accepted history. Other untruths, you at least have the consensus on side for now.

But, the consensus still favours String Theory. You've made a decision not to do that, so you are willing to question consensus which is great. This is presumably a recent thing with String Theory as I've noted your support for it in the past. Or at least a dramatically more positive prognosis.

So what about Inflationary Theory? You characterize that it makes predictions. What is a prediction, what does that mean to you?

Traditionally it means that which comes undeniably from the heart of a theory, in which no modifications are possible in which the prediction does not happen, without mutilating the theory beyond redemption.

The ways that gets nailed down is via distinction between up-front tweaking of a theory to encapsulate some development into the theory. Normally that's at the level of an explanation.
And...a prediction of something that hasn't been observed and probably hasn't been anticipated. The reason that one is the prediction is simply because it's the highest grade of evidence that no cheating and/or rationalizing has taken place. No psychology in there, in principle. Which obviously matters a great deal.

Intrinsic from that - a consequence if you like of that - is that theories that can be modified - and if they can it is usually effectively infinite the number of models - cannot ever predict.

In the case of Inflationary Theory, there is no incidence of a fundamental consequence coming out of Inflationary Theory that was not already in the public domain. Not one.

I'm sure you must be entertaining this reality privately, because it is closely linked in with problems in String Theory. You can't think seriously about the problems in one, with getting an 'oh shit' moment about the other. They are not linked as theories by the way, they are linked in terms of sharing the same basket of problems.

A further problem is that inflationary theory is a multiverse theory. I know it gets spoken of as 'tending' to give rise to a multiverse, but Guth has all but admitted that it is not possible to get an inflationary model that doesn't require a multiverse. His most recent words on this is "It's very hard. It's not impossible I don't think"....the implication being he hasn't got one and isn't expecting to get one.

One of his co-founders of inflationary theory has been much more blunt and upfront about it. He has said that there is simply nothing in the idea that allows the process to stop.

I think you came out against the multiverse last week. I think that was the right scientific stance to take. But it does not end with String Theory.

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

"Ethan this is completely untrue. The cosmic web and large scale structure was a complete surprise and shock when technological advances began knocking out data in the late 1980’s."

Chris, this is completely untrue. The cosmic web and large scale structure was EXPECTED and CONFIRMED when technological advances began knocking out data in the late 1980's.

I know. I was there.

"this much is actually conventional accepted history"

Since Ethan is part of the conventional body, and you claim he's wrong, this is self-evidently a load of self-serving codswallop.

"I’m sure you must be entertaining this reality privately"

The dunning-kruger retard will always project whatever is necessary into the minds of others and present it as stated fact rather than a complete ass-pull. The DK sufferer will not let a little thing like lack of data to stop them "knowing" that they are right.

"So what about Inflationary Theory? You characterize that it makes predictions. What is a prediction, what does that mean to you? "

READ THE FUCKING DICTIONARY RETARD.

You want to waste the time of people who have enough dealing with people who at least locate themselves on a regular basis in reality. You're an occasional visitor to the shores of real life, though.

If you don't know what a bloody prediction is, how on earth can you know that the CMB et al weren't predicted????

"A further problem is that inflationary theory is a multiverse theory. "

a) No, inflationary theory is not a multiverse theory.
b) Even if it were, it would not be a problem.

You want to make it out to be so that your "keen insight" will be an amazement to all, and that your pontifications are held as profound rather than profoundly empty.

"but Guth has all but admitted "

a) why is that one person right?
b) so even you admit that he *hasn't* admitted any such thing. You have to reinterpret it "appropriately".

"One of his co-founders of inflationary theory has been much more blunt and upfront about it. He has said that there is simply nothing in the idea that allows the process to stop. "

Nothing in there that says it is a multiverse theory, and this is the claim you assert is upfront about it.... Your very best and clear claim has the least support for your contention in it.

You have the right to your own opinions (however much you try to suppress those of others) but not your own facts.

And you DEFINITELY don't have the right to insert words into other people's heads just so that you can fluff up your own "amazing knowledge". It's the right to your OWN opinions, not the right to assert what other people's opinions are.

What is a prediction, what does that mean to you?

Traditionally it means that which comes undeniably from the heart of a theory, in which no modifications are possible in which the prediction does not happen, without mutilating the theory beyond redemption...

...Intrinsic from that – a consequence if you like of that – is that theories that can be modified – and if they can it is usually effectively infinite the number of models – cannot ever predict.

Your conclusion merely follows from your idiosyncratic definition of prediction Your entire idea is overly restrictive and doesn't (IMO) reflect how actual science is done or how actual scientists behave. AFAIK the vast majority of scientists have no problem with calling an ancillary, mutable, theory-based assertion about the future a "prediction."

This is because theories are often imperfect or approximate models, and a 'failed' prediction often leads to an investigation of whether a revised, more accurate version of the same model would have agreed with the observation. This is particularly true of theories that rely on a lot of computational power; it would be foolish to demand that every theoretician spend $millions on the best possible supercomputing-powered version of their theory before publishing a "prediction," or claiming that if they don't, their theories can't make predictions. No, the much more rational approach is to first do a relatively cheap theoretical calculation and prediction, then use empiricism to test whether reality is in the ballpark of your prediction, and then iterate the theory as needed. You buy a little bit of theory development, test whether its reasonably close, then if it is you buy a little bit more.

Another, even more mundane, reason your standard is idiosyncratic and overly restrictive is that humans often make mistakes. Theoreticians too! A failed prediction can lead to a review of the math, the assumptions, etc. and the discovery and correction of a mistake. Does this mean the theory is not predictive, because it could be modified after review? No. What it means is that a theory's predictions may change as our understanding of the theory gets better.

In short, actual scientific theory development is (often) much more incremental and iterative - and far less binary - than you make it out to be. The indisputable, binary, once and for all type test is nice when you can get it, but it isn't the norm and its certainly not required before an hypothesis or theory can be considered 'predictive.'

I actually agree with everything you just said. You'd think that's to contradict what I just said (not you personally necessarily). But it ain't so, because the end to end journey of discovery is long. That be all end all prediction has to happen but these days it gets talked about as if it has to happen at or near the beginning. What happens there is whatever it takes.
There's nothing illegitimate about String Theory or Inflationary Theory per se. What is illegitimate is the conduct and/or misconceptions within those communities

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

Sorry...I accidently pressed 'send' when I wasn't finished. But I just got called to dinner so I'll try to give you the fuller answer your response deserved in the near future (hopefully later today) bye

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

That be all end all prediction has to happen

No, it doesn't, for several reasons. I will mention the two I think are most important. Firstly, theory selection is relative. We use the best available. If all available theories fail some big prediction, that doesn't mean we put them all aside. It means we use the one that does the best. There will never be any such objective test (as you seem to think there is) which will cause scientists to reject a theory unless there is a better replacement. This is a very practical and pragmatic decision: we will do experiments. We must make experimental design choices. Which means we have to base design choices on some idea of what parameters are most likely to yield an informative result. Those ideas are theory. Being utterly theory-free is simply not an option. So we use the best available, even when the best available doesn't make predictions where it should and gets other important predictions wrong.

Secondly, failing a big prediction doesn't mean utter rejection. It means we don't use that theory in that domain. The classic examples are NM vs. QM and NM vs. GR. NM failed some pretty big tests, but we still use it in the domains where it's accurate. We only use QM and GR in the domains where it isn't. Was there an end all be all test for NM? No. It turned out to be inaccurate under a number of very different conditions (small particles; high acceleration or gravity fields) which caused science to reject it as 'fundamentally' true. But after these many small failures, we continued using it. Because failing an end all be all test doesn't necessarily end all use in science.

You're still painting science with this big bold brush using only two colors. The reality is far more nuanced. Many shades of gray existing between a nice black confirmed theory and a rejected white one. There are also several dimensions to most theories, whereby a theory may be unappealingly white in one dimension but nicely black in another.

But, the consensus still favours String Theory.

"Consensus." I do not think that word means what you think it means.

A further problem is that inflationary theory is a multiverse theory. I know it gets spoken of as ‘tending’ to give rise to a multiverse, but Guth has all but admitted that it is not possible to get an inflationary model that doesn’t require a multiverse.

You're also failing to distinguish between trivial "multiverses" that all have the same physics and the flight from science that is the string landscpe version.

Eric - you're buying into a synthetic worldview that only this and the last generation of frontier scientists have entertained. And that is during a period where there has been NO fundamental progress whatsoever. Of course, you can redefine 'fundamental progress' to mean something else, something softer. Which is what you are doing. But the problem is, this is about objective discovery. And the learning of the scientific revolution is that objective discovery is extremely hard. Ergo - the scientific revolution only ever happened once, in one place. It's hard.
And the nonsense that you are talking and buying into is never, ever, going to produce progress.

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

Narad - No I'm thinking specifically of the String Landscape. The misdirection that has been coming of the string community is outrageous. Apparently it's because they all have spiritual experiences that they have convinced themselves that the cause is so just that playing politics and misrepresenting the status of the theory to funders is acceptable.
What they may not have thought through carefully is that using misrepresentation to obtain public funds is a criminal offense.
But you and I. Let's talk about the dualities OK? Tell me, how is it possible that using over-complete functions to fix a duality, results in knowledge of a fundamental basis, without all the adjustments that get made also being of a fundamental character? And if they are - despite being inherently psychological - why are not included in the final piece?

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

Narad says [But, the consensus still favours String Theory.

“Consensus.” I do not think that word means what you think it means.]

Well, since I have no clue what you mean, I can't really answer that.

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

People - I'm willing to argue with you. But you will have to get Ethan to post a comment with his permission. Because this is not in the groove of his commercial theme, and I don't want to do damage to what he's trying to do. Otherwise - I'm going to have to leave it here, so to keep with my pledge not to engage extended arguments and flood the place. Best.

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

Sorry I didn't see Wow there. Hi Wow, I'm probably going to ignore you going forward until you clean your act up, but since I'm responding to you here I will answer anything relevant.

"I know. I was there."

You weren't there in a noteworthy capacity Wow. I'd be able to tell had you been. What you're saying is silly and wrong, as 10 or 20 minutes of sensible googling confirm to anyone interested. What they'll find is a serious crisis at the time, with leading scientists talking about giving up due to one shock after another coming through.

But anyway, Wow, so: tell me, what part of foundational BIG BANG [at the time] hypothesis implies - to you - all this multilevel structure and weblike empirical character?

I mean, I thought the cosmic web was unobserved at that time, and impossible to predict via Big Bang reasoning, for being inexplicable absent DARK MATTER hypothesizing, which at the time merely an observed anomaly in spirals?

I'm obviously very misinformed Mr "I know - I was there"

"Since Ethan is part of the conventional body, and you claim he’s wrong, this is self-evidently a load of self-serving codswallop."

I've never seen Ethan claim to be an expert in history of science. I think he's honest. So, it would take a lot more than what looks like a mistake for me to begin to think he actually lying. He's made it clear that he may make mistakes and welcomes any pointed out, which he will duly double check and make corrections. I think that is what he will do.

"The dunning-kruger retard will always project whatever is necessary into the minds of others and present it as stated.."

Are you aware of the fact you are mirroring what I said to you yesterday, in that I asked you not to tell me what to think? You do that a lot, and it is *conventionally* regarded as dishonest.
In answer to your point. Have you asked him? I think he must be at least conflicted, due to what he has said about String Theory. So I have, at least, a reasoning. Do you?

"READ THE FUCKING DICTIONARY RETARD."

Oh silly me. Silly the current crisis in science acknowledged by the leading scientists of our day, as to the character of science. Silly them for not checking the dictionary.

"a) No, inflationary theory is not a multiverse theory."

Really, oh well that's alright then. So...which derivation is in fact, not?

" b) Even if it were, it would not be a problem."

This is fine Wow. You believe in the multiverse as legitimate in the scientific context. You're not alone.

The reason a large and growing contingent do not, or are extremely uncomfortable with the notion, is that it is, in principle, sterile. Nothing can be built upon it. Nothing can bypass it (because it's infinite in extent). And so for that reason if we adopt it now, we can be sure that it will still be there in our best knowledge, exactly where it is now, in 500 years.

So all we are saying, those who think it would "be a problem even if it was", whom with which from what he said last week, Ethan counts himself among, is this: The multiverse may be true, but also true is that multiverse - even if true - is scientifically sterile. But that's not a reason to deny truth - which it may be ; we get that. But all we are saying is that the multiverse is always, and will always be available. So why not hold it back, as long as humanely possible, so as to give everything humanely discoverable that is NOT scientifically sterile, a chance to show itself? Let's hold back the day that science died.

"a) why is that one person right?"

Well, besides being the founder he is also actively the pre-eminent figure in that sector. Doesn't mean he's right, but it does make him the most reasonable subject for quotation most fairly to represent the status of things to the most possible people, arguably. That doesn't include you Wow. I respect that. And disregard it, duly.

b) so even you admit that he *hasn’t* admitted any such thing. You have to reinterpret it “appropriately”.

I think you'll find if you formalize with integrity which I'm not confident of in your case, currently, due to the mirroring psychological trickstering. But if you do, and you are, I think you'll find it follows.

[“One of his co-founders of inflationary theory has been much more blunt and upfront about it. He has said that there is simply nothing in the idea that allows the process to stop. ”

"Nothing in there that says it is a multiverse theory, and this is the claim you assert is upfront about it…. Your very best and clear claim has the least support for your contention in it."]

Well what can I say Wow. I mean, sure...maybe it doesn't mean what I said it meant. Maybe it means some other thing. I admit that the paraquote leaves much potential open.

However, all one can do is faithfully quote, both the approximate wording AND the context in which the person being quoted fixed what, he at least, thought he meant by his words, which was, effectively, that it was a multiverse theory.

But Wow doesn't think so, and he'll obviously have to take that on board.

By Chris Mannering (not verified) on 08 Jan 2016 #permalink

Goodness. No matter that eric was kind and considerate and used no intermperate language, you STILL won't accept "nope" for an answer, Chris.

Given you won't no matter what form the rebuttal, why the fuck should anyone try to use language other than that which they feel appropriate to the person or situation it is used?

You're here bullshitting. No more, no less.

"Eric – you’re buying into a synthetic worldview "

Shit, that's a load of woomancer right there.

Either "worldview" is the paradigm people use to determine how to approach reality, in which case EVERY SINGLE FRIGGING WORLDVIEW IS SYNTHETIC, or you're using "synthetic" as some woomancer hippy gaia proponent dog whistle for "bad".

When in actual fact, you don't know what the hell you're talking about, but you won't stop telling everyone (even old Nads there) that they're all wrong because you don't have a synthetic worldview.

Whatever the fuck that is supposed to mean for accuracy...

"“a) No, inflationary theory is not a multiverse theory.”

Really, oh well that’s alright then"

OK, finally admitting your error. Well done.

"So…which derivation is in fact, not? "

Oh, apparently you aren't. Still 100% ignorant retard as before.

Shame.

If chris here lives up to his hype one way to get the fuckwit to shut up is to swear at him.

If you don't all he will do is reply with some variation on "You're utterly wrong!".

You wouldn't expect a woomancer to change their mind, would you?

And if they are – despite being inherently psychological – why are not included in the final piece?

I have no patience with Bad Fazzm, sorry.

Wow,

At this point It really doesn't matter what you think. In any professional association if you 'expressed' yourself as you do here in this forum, you would be shown the door by an armed escort.

You may in fact actually be right about something on occasion, but since you can't keep your mouth under control you have absolutely no ability to persuade anyone of anything except that you are an obnoxious jerk with no self editing ability whatsoever.

Please get professional help for your coprolalia and quit trashing Ethan's blog.

"Wow,

At this point It really doesn’t matter what you think"

Then why tell me?

Ah, denigration. How rude.

"In any professional association"

This is a blog. Please check the viewer and note that it is a webbrowser, indicating this is not a work venue, but an internet one, and also note the URL contains "scienceBLOGS". So what you think would happen in any professional association really doesn't matter.

And in a professional association, someone who kept blabbering on about women should STFU, they would not only be banned but also charged by the government.

Yet somehow, teabagger's myscogynistic rants don't warrant any mention when they turn up. If you're fine with those posts, then your opinion really REALLY doesn't matter on what you claim to be "proper" in a forum.

"You may in fact actually be right about something on occasion"

But you don't count them, do you, because you wish to be a hero. You also minimise the count so as to be as little "contaminated" with accepting what I do without being obvious in your bias after this willful blindness of those who wish to berate me being pointed out by myself earlier.

"you have absolutely no ability to persuade anyone of anything "

For godbotherers and woomancers, they ARE NOT ABLE TO BE PERSUADED. See William Craig v Bill Hye: there is no evidence or argument that is possible to make that will make him change his mind.

Why do you put rat poison down in a place where rats are a problem? You make the environment toxic to them to get them to leave, because there's no avenue to persuade them to moderate or in any way change their actions.

You would prefer rat infestation to having to think about poor homeless orphan rats. Because you think that empathy is warranted and somehow proves you a nice person.

"you are an obnoxious jerk with no self editing ability whatsoever. "

If I cared about your opinion, or any other blowhard on the internet, this might have some traction, but I don't so it doesn't. You don't care about obnoxious jerks. Only those who do what you think should not be done, negating any right you have to arbitrate what is allowed on the internet.

"Please get professional help for your coprolalia and quit trashing Ethan’s blog."

Godbotherers and woomancers first.

Oh, no, you think that these "opinions" should be allowed, because

a) you are bathed in godworship, and this insanity is normalised to you and you are blind to its inimical effects on society. Good people are good DESPITE religion, not BECAUSE of it. And moderate religion is the gateway drug to ISIS-like murderous fundamentalism.

b) you WANT to believe in freedom of speech, but when faced with words you do not agree with being said, you cannot accept the platitudes and homilies of free speech. Therefore it MUST be because of a moral flaw of another, not that you aren't really for the free speech like you claim it. After all you KNOW you are a good person!

c) You "know" you are a good person, therefore anyone who does something you yourself do not think you could do (despite you having done so, but this is "justified" as a response to me, despite the fact that most of the posts I make are responses to others attacking me, so justification is actually rationalisation), it must be because they are a BAD PERSON. This is nothing other than self preserving self-deception.

If all people did in a professional institution was to complain about other people, they would be thrown out for being disruptive.

For that "reason" nobody cares what you have to say. Only those wishing to join the witchhunt will join you, and they were never going to think differently anyway.