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from blog Cosmic Variance:
arxiv Find: A Realistic Cosmological Model…
The title is a bit misleading; what is being referred to is not a realistic cosmological model at all. But it’s interesting to see that not every professional astronomer believes in the Big Bang model; there are still some out there who are sticking with the Steady State theory. Seriously.
But it’s an interesting case study in how science works. Reading Burbidge’s paper, the parallels with anti-evolutionists are striking. In both cases, one is repeatedly told that the establishment’s supporter’s can’t prove that their theory is correct. Which is undeniably true, as science never proves anything; it just accumulates evidence, and in the case of the Big Bang and natural selection, the evidence puts the case beyond reasonable doubt. Which doesn’t imply that there are no interesting questions remaining to be addressed. For both the Big Bang and natural selection, many of the details concerning the way in which the broad framework is specifically implemented in the real world remain to be answered. And in both cases, the skeptics like to pretend that open questions about the details are the same as open questions about the framework. But they’re not.
Nevertheless, one of the virtues of the tenure system is that a Big Bang skeptic can keep their position as a professor of physics, writing heterodox articles and submitting them to the arxiv. And this really is a virtue, not a flaw. Geoffrey Burbidge has done lots of respectable work in observational astronomy. Long ago, he and his wife Margaret collaborated with Fred Hoyle and Willy Fowler on an important paper that helped established the theory of nucleosynthesis in stars. Part of the motivation for the paper was the realization that conditions in the Big Bang were not right for synthesizing elements much heavier than lithium — you could explain the universe’s helium abundance, but not the existence of carbon and iron and so forth. Hoyle, of course, was one of the originators of the Steady State theory, and that was certainly part of his motivation at the time. As it turns out, in the real world, some elements are synthesized in the early universe, and some in stars, and some in supernovae; the real world can be a messy place.
Would a young cosmologist who didn’t believe in the Big Bang be offered a faculty job, or receive tenure, today? Probably not. Faculty jobs are scarce commodities, and a university is going to want to hire people who will do interesting and productive work that is of some use to the wider community. Believers in the Steady State model aren’t going to produce such work, any more than creationists or astrologers or experts in the plum-pudding model of the atom. And eventually support for the model will fade away entirely, opening the door for the next generation of heterodoxies.
A Realistic Cosmological Model Based on Observations and Some Theory Developed Over the Last 90 YearsFor those with any lingering doubts, the Big Bang model — the idea that the universe has evolved from a hot, dense, smooth initial state — is correct, and the Steady State model should have been put to bed a long time ago. Evidence for the Big Bang is overwhelming. It’s a model that keeps making predictions, which keep turning out to be correct, while the Steady State theory made many predictions that turned out to be wrong.
Authors: Geoffrey Burbidge
Abstract: This meeting is entitled “A Century of Cosmology.” But most of the papers being given here are based on work done very recently and there is really no attempt being made to critically review what has taken place in the last 90 or 100 years. Instead, in general the participants accept without question that cosmology equates to “hot big bang cosmology” with all of its bells and whistles. All of the theory and the results obtained from observations are interpreted on the assumption that this extremely popular model is the correct one, and observers feel that they have to interpret its results in terms of what this theory allows. No one is attempting to seriously test the model with a view to accepting it or ruling it out. They are aware, as are the theorists, that there are enough free parameters available to fix up almost any model of the type.
The current scheme given in detail for example by Spergel et al (206, 2007) demonstrates this. How we got to this stage is never discussed, and little or no attention is paid to the observations obtained since the 1960s on activity in the centers of galaxies and what they imply. We shall show that they are an integral part of a realistic cosmological model. In this paper I shall take a different approach, showing first how cosmological ideas have developed over the last 90 years and where mistakes have been made. I shall conclude with a realistic model in which all of the observational material is included, and compare it with the popular model. Not surprisingly I shall show that there remain many unsolved problems, and previously unexpected observations, most of which are ignored or neglected by current observers and theorists, who believe that the hot big bang model must be correct.
But it’s an interesting case study in how science works. Reading Burbidge’s paper, the parallels with anti-evolutionists are striking. In both cases, one is repeatedly told that the establishment’s supporter’s can’t prove that their theory is correct. Which is undeniably true, as science never proves anything; it just accumulates evidence, and in the case of the Big Bang and natural selection, the evidence puts the case beyond reasonable doubt. Which doesn’t imply that there are no interesting questions remaining to be addressed. For both the Big Bang and natural selection, many of the details concerning the way in which the broad framework is specifically implemented in the real world remain to be answered. And in both cases, the skeptics like to pretend that open questions about the details are the same as open questions about the framework. But they’re not.
Nevertheless, one of the virtues of the tenure system is that a Big Bang skeptic can keep their position as a professor of physics, writing heterodox articles and submitting them to the arxiv. And this really is a virtue, not a flaw. Geoffrey Burbidge has done lots of respectable work in observational astronomy. Long ago, he and his wife Margaret collaborated with Fred Hoyle and Willy Fowler on an important paper that helped established the theory of nucleosynthesis in stars. Part of the motivation for the paper was the realization that conditions in the Big Bang were not right for synthesizing elements much heavier than lithium — you could explain the universe’s helium abundance, but not the existence of carbon and iron and so forth. Hoyle, of course, was one of the originators of the Steady State theory, and that was certainly part of his motivation at the time. As it turns out, in the real world, some elements are synthesized in the early universe, and some in stars, and some in supernovae; the real world can be a messy place.
Would a young cosmologist who didn’t believe in the Big Bang be offered a faculty job, or receive tenure, today? Probably not. Faculty jobs are scarce commodities, and a university is going to want to hire people who will do interesting and productive work that is of some use to the wider community. Believers in the Steady State model aren’t going to produce such work, any more than creationists or astrologers or experts in the plum-pudding model of the atom. And eventually support for the model will fade away entirely, opening the door for the next generation of heterodoxies.
Posts
November 17th, 2008 at 12:30 pm This seems like a good time to ask a general question: so far as I can see, there is no credible alternative to the Big Bang; but it also seems that the Big Bang is not what it used to be. Where it once was mostly thought of as an absolute beginning of a singular universe from something like a mathematical singularity, it is now simply “the idea that the universe has evolved from a hot, dense, smooth initial state” without the implication that it was any way unique or inexplicable.
I’m not talking about formal models of the Big Bang, which, from my layman’s perspective, appear to be all over the place, but imaginative pictures that put the various equations in a context. What used to be physics’ answer to Let There Be Light is now spoken about more often as a stage in the on-going and perhaps interminable history of things, important to us for parochial reasons, but just another bubble in the cosmic champagne. The pictures matter, even though they are neither evidence or arguments in themselves, because they make some theories appear natural and plausible, others artificial and far fetched. What do you guys thinks about that.
November 17th, 2008 at 1:04 pm If Fred Hoyle was an advocate of the Steady-State theory, why would he work on nucleosynthesis in stars? Doesn’t the theory of stellar nucleosynthesis support the Big Bang theory by explaining how heavy elements could be created after the Big Bang?
I’m not arguing against anything you wrote; I’m just confused because you make it sound like Hoyle developed the idea of stellar nucleosynthesis *because* of his connection to the Steady-State theory.
November 17th, 2008 at 1:07 pm I was going to to write a longer comment — but now I’ll just second Jim Harrison, as I had the same thoughts while reading the post. The fact that it now seems unlikely that the big bang started from a singularity hasn’t penetrated very far into public consciousness. — “another bubble in the cosmic champagne…” - I liked that.
November 17th, 2008 at 1:09 pm joe– If you don’t believe in the Big Bang, how do you account for the existence of heavy elements? (Early BB proponents thought they could make all the elements in the early universe, but that turns out not to work.)
Jim– The Big Bang theory was always “the idea that the universe has evolved from a hot, dense, smooth initial state.” It’s to be distinguished from the “Big Bang” event itself, the singularity at the beginning of the universe — which was always speculative and mysterious, and remains so. The BB theory is in better shape than ever, as new observations help us understand how the universe evolved.
November 17th, 2008 at 1:12 pm From a pure layman’s perspective, comparing models like Steady State, which you seem to equate with creationism to things like eternal inflation, which seems to have some street cred in the scientific community, it is difficult to see why one is clearly more credible than the other from a strictly observational point of view.
Perhaps you can help clarify why I should semi-believe in eternal inflation but tell my local school board that they should no longer teach the Steady State model except in a history of science class.
I am not trying to be a wiseguy here. I just would like a brief case made based on observational evidence for Eternal Inflation and against the Steady State model. I realize they are not apples to apples. But in some ways to me Eternal Inflation somewhat echoes the Steady State model in a meta-conceptual** way.
e.
** meta-conceptual - word just made up for this post but is now being trademarked for future use
(tm) elliot tarabour 2008 all rights reserved.
November 17th, 2008 at 1:18 pm I think the big bang theory is right on. God spoke, there was a BIG BANG, and there it all was.
November 17th, 2008 at 1:40 pm Why must there have been only ONE big bang in the current universe (as opposed to others 13 billion light years or more distant)? Why not a few small bangs, creating different accelerations from various points?
November 17th, 2008 at 1:56 pm […] Het echtpaar BurbidgeHet begint langzamerhand een uitstervend ras van sterrenkundigen te worden: degenen die niet in de Big Bang geloven, de theorie dat het heelal met de oerknal is ontstaan. Eén van die sterrenkundigen is niemand minder dan Geoffrey Burbidge, die in 1957 (51 jaar geleden dus) samen met z’n vrouw Margaret Burbidge, Fred Hoyle en William Fowler een beroemd artikel schreef over nucleosynthese in sterren. Hoyle en het echtpaar Burbidge kennen we echter ook van de tegenhanger van de Big Bang-theorie: de Steady State theorie. Die stelt dat het heelal er altijd was en altijd zal blijven uitdijen. Niks oerknal, maar continue uitdijing in een eeuwig heelal. Als verklaring voor de door Edwin Hubble waargenomen uitdijing en de daaruit volgende afname van de dichtheid van het heelal geloofde men dat er continue materie in het heelal wordt gecreëerd. De steady state-theorie is niet door het echtpaar Burbidge opgesteld: hij is in maart 1948 onafhankelijk van elkaar door zowel Hermann Bondi en Thomas Gold als Fred Hoyle opgesteld als tegenhanger van de Big Bang-theorie uit onvrede met het feit dat er in die theorie een begin (een “scheppingsmoment”) wordt aangenomen. Maar Geoffrey en Margaret Burbidge zijn wel jarenlang dé verkondigers van deze theorie geweest en da’s deze week weer gebleken. De 83 jarige Geoffrey Burbidge heeft namelijk op arXiv een artikel online gezet waarin hij alle markante punten van de steady state weer eens eventjes op een rijtje zet. Hoe moet je de steady state-theorie anno 2008 inschatten? Valt er iets voor te zeggen? Mijn stelling is van niet. Ik vrees dat Burbidge en de weinige anderen tegen kosmische windmolens vechten. De aanwijzingen voor een oerknal 13,7 miljard jaar geleden zijn namelijk indrukwekkend en ik ga ze hier niet noemen, omdat ze al zo vaak in de astroblogs belicht zijn. Maar het mooie van wetenschap is dat zelfs met die stortvloed aan bewijzen en aanwijzingen je een andere mening kunt zijn toegedaan en dat je daarin wordt gerespecteerd. Niemand die Burbidge verbiedt om dat artikel te publiceren. Ook al is niemand het verder met hem eens. Beetje sneu, nietwaar? Bron: Cosmic Variance. […]
November 17th, 2008 at 2:35 pm It’s a real puzzle to me how it is that someone like Burbidge (clearly a smart man) can still take the steady-state model seriously. Perhaps he is unconsciously strongly attached to it because it is his ‘baby’? If so he lacks the ability to be objective. If I recall, one of Sagan’s sayings in his ‘Baloney Detectino Kit’ is the idea that one should make every effort to *not* get too attached to an idea just because it is your own…
“And eventually support for the model will fade away entirely, opening the door for the next generation of heterodoxies.”
Right, since, well, Burbidge is quite old…
November 17th, 2008 at 2:48 pm Is there a reasonable difference between (1) ‘does not believe in the big bang’ and (2) ‘goes to great lengths to argue against the big bang in the interests of good science’?
What Burbidge believes is not really interesting, it’s whether his arguments hold up that’s the important thing.
Actually the whole question of ‘believing’ in a scientific context is quite subtle, I think.
November 17th, 2008 at 2:51 pm Of course, with arxiv, the dirty laundry of the living fossils is mixed in with real papers for all to see. Even if the paper is unpublishable, this will shamble around the internet as long as it can find a willing host.
I don’t know if that’s necessarily a bad thing, but how to deal with crackpotism is something to think about.
November 17th, 2008 at 3:49 pm I’m over-whelmed. Or over-whelming. Some kind of whelmishness, for certain.
November 17th, 2008 at 4:43 pm There are also parallels between cosmology and the evolution debate over the question “how did it all begin?”
As Sean says, the Big Bang theory does not address the first cause or even that it might not be a unique event. In the same way, the theory of evolution does not address abiogenesis — how life began — or whether or not it was a unique event.
The evidence for both the Big Bang and evolution *is* overwhelming (despite what the naysayers claim) but the evidence for how it all started (in both cases) is, at best, extremely sketchy bordering on the non-existent.
Creationists like to conflate the two issues in an attempt to muddy the water for the whole field in the eyes of the general public. While it’s true that you can’t have the evolution of the Universe in general or life in particular without a beginning of some kind, the fact that we don’t know what that beginning looks like (and may never do so) doesn’t in any way invalidate or water down the mountains of evidence in support of both theories.
November 17th, 2008 at 5:57 pm It’s still the ultimate irony that Lemaitre originally proposed BBT, the primordial atom, as a way to provide scientific validity to creationism. An eternal universe just didn’t fit the narrative structure of monotheism.
November 17th, 2008 at 7:08 pm Elliot– I’m not sure what “semi-believe” means. Eternal inflation is a speculative idea about the early universe, which has some attractive features, but is far from established. It deals with an epoch about which we have very little evidence to decide things one way or another. The Steady State model concerned the current universe, made predictions, and they came out wrong. There is not much relationship between them. Remember, the primary feature of the Steady State theory is not “the universe is eternal,” it’s “the universe is unchanging” — in particular, it has always had the same temperature. That’s been ruled out a million different ways, and the remaining SS proponents have been forced to abandon nearly all of the original model.
Lily– There’s no reason why there couldn’t have been many bangs. Many of us are quite interested in the possibility, and have been investigating it.
John– I don’t think that’s right; Lemaitre always resisted drawing theological conclusions from the Big Bang. He proposed the idea because it was a consequence of general relativity.
November 17th, 2008 at 7:24 pm In the first few pages of this article, there is some useful history if you set aside Burbidge’s occasional polemical eruptions. For example, on page 5 he does answer the question posed above of what led Hoyle and B^2FH to found the theory of stellar nucleosynthesis. Most of this history can be found in books, of course, but that does not make it uninteresting. But in the present paper, around page 7 we come to yet another Burbidgean idea for the origin of the CMB and for active galaxies, and the wheels come off.
Incidentally, as Burbidge points out one piece of evidence for stellar nucleosynthesis was Merrill’s detection of Tc-43. When I was a fresh-faced young postdoc at Santa Barbara Street, on the second or third day the great George Preston burst into my office and by way of introduction (his office was across the hall) announced “Did you know that this is the office in which TECHNETIUM was discovered in STARS??!”