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lpetrich
Skeptic Friend
USA
74 Posts |
 Posted - 12/23/2001 : 01:24:48
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Richard Carrier's "Was There a Big Bang? I Honestly Don't Know", URL: http://www.infidels.org/library/modern/richard_carrier/bigbang.html
Any opinions on it? Too much of the article resembles classical crackpottery Like his approving mention of a conspiracy theory in which the Big Bang theory is supported mainly because BB supporters only allow other BB supporters to get telescope time. In such theories, Halton Arp often becomes a latter-day Galileo; RC also approvingly mentions HA. Here I'll analyze his critiques point-by-point:
RC: "(1) Expansion does not entail that it all began at a point."
RC: "We have absolutely no evidence that the universe began at a point--that is entirely a theoretical invention, as yet untested, and unlikely ever to be testable, yet it is the essence of the very "Big Bang" concept itself." and "... all too often big bang proponents confuse evidence for an explosion with evidence for the origin of all space and time."
LP:
A straw position -- and one unrelated to the bulk of the Big-Bang evidence.
He also mentions other causes of redshifts, such as contraction and scattering off of intergalactic dust and magnetic fields; however, contraction is extremely difficult to take seriously as an explanation for cosmological redshifts, and when scattering causes frequency shifts, it obscures the original direction of the light.
He mentions Eric Lerner's discussion of radiation pressure as a Universe-expansion mechanism, but it's rather easy to show that it would produce too small a "kick".
RC: "(2) The microwave background radiation has too many other explanations."
He mentions approvingly the theory that it is the scattered light of very distant stars; however, it looks like something optically thick at nearly constant redshift. He also mentions the discovery of intergalactic dust and magnetic fields; however, these do not significantly obscure a variety of distant objects, which implies that they are optically thin over Hubble sizes.
RC: "(3) The proportion of light elements to heavy is far too muddled to stand as a proof."
Actually, it's reasonably consistent with Big-Bang nucleosynthesis. And there are indirect ways of estimating how much helium could have been formed in the cores of stars, by comparing heavy-element and helium abundances; they fall on a straight line that hits zero heavy elements at about 25% helium by mass.
RC: "(4) Observations of differences in aggregate cosmic phenomena over time are inconclusive."
RC: "That things were different in earlier epochs is not inconsistent with an oscillating steady state theory or multi-bang theory or phase-change theory, or theories involving cosmic cycles, or still other possibilities that are too plausible to be simply dismissed, and that no one is even trying to eliminate. ..."
LP:
However, that does mean that the galaxy era, as it might be called, has been very Big-Bang-like. One problem for many of these theories is that they end up including Big-Bang-like phases, making them difficult to distinguish from a single Big Bang.
RC: "(5) The 2nd law of thermodynamics does not entail a Big Bang."
Straw position.
RC: "(6) A flat universe is entailed by almost every other possible theory. "
Not to mention other resemblances to the single-BB theory that successful alternatives end up having.
And here is some of his evidence against the Big Bang:
RC: "(1) How can there be galaxies that are older than time?"
RC's first examples suggest one of the problems with dealing with popularizations; they like to translate reported results into familiar terms, such as a redshift into a distance. However, the derived distance depends on the dynamics of the Universe's expansion such as the value of the Hubble constant, and a distant galaxy's present distance may be significantly greater than its time-of-observation distance.
A more serious problem is that Big-Bang-based estimates of the Universe's age are sometimes less than the estimated ages of the oldest stars.
RC: "(2) Where is all the mass?"
True, a lot of the mass in the Universe appears to be material that interacts only very weakly with its readily-observable material, but I don't think that that's a fatal difficulty, because some weakly-interacting particles are already known to exist (neutrinos), with additional such particles being an expected consequence of various Grand Unified Theories.
RC: "(3) Where did all the superscale structure come from?"
True, getting that right has been somewhat difficult, but there are some promising leads, such as frozen quantum fluctuations from an exponential-expansion inflationary era, the side effects of cosmic strings, and so forth.
But counter to that is abundant support for the standard Big Bang model to at least the nucleosynthesis era and theoretical reason to believe that it had continued from a quantum-gravity epoch (Hawking's singularity theorems).
Bad Astronomy: http://www.badastronomy.com/phpBB/viewtopic.php?topic=300&forum=1
Internet Infidels: http://ii-f.ws/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=10&t=000545
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ljbrs
SFN Regular
USA
842 Posts |
Posted - 12/23/2001 : 16:26:11 [Permalink]
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Thank you for your careful replies to Richard Carrier. I enjoyed reading them; however Carrier's statements have a nausiatingly familiar ring. I also think that many similar scientific notions have been very well-countered by Dr. Ned Wright at his wonderful (a favorite of mine) Cosmology Tutorial site:
http://www.astro.ucla.edu/~wright/cosmolog.htm
I always enjoy your writing wherever I find it. Each time, it seems to me to have a *ring* of scientific accuracy.
ljbrs 
"The only real way to reconcile science and religion is to set up something that is not science and something that is not religion." (H.L. Mencken)
Edited by - ljbrs on 12/23/2001 16:29:27 |
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lpetrich
Skeptic Friend
USA
74 Posts |
Posted - 12/24/2001 : 21:27:08 [Permalink]
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quote:
Thank you for your careful replies to Richard Carrier. I enjoyed reading them; however Carrier's statements have a nausiatingly familiar ring. ...
I always enjoy your writing wherever I find it. Each time, it seems to me to have a *ring* of scientific accuracy.
ljbrs
Thanx. I'm flattered. It also seems to me that theories like the QSSC involve too much ad hoc physics. The Big Bang, by comparison, is much more "natural", requiring only relatively plausible additional features, such as weakly-interacting massive particles. IMO, the Big Bang's biggest puzzle is what happened at its beginning, in the quantum-gravity epoch. But this is because we lack a successful theory of quantum gravity.
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ljbrs
SFN Regular
USA
842 Posts |
Posted - 12/25/2001 : 12:07:56 [Permalink]
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You are welcome.
ljbrs
"Nothing is more damaging to a new truth than an old error." Goethe |
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ljbrs
SFN Regular
USA
842 Posts |
Posted - 01/02/2002 : 20:19:56 [Permalink]
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quote:
Thanx. I'm flattered. It also seems to me that theories like the QSSC involve too much ad hoc physics. The Big Bang, by comparison, is much more "natural", requiring only relatively plausible additional features, such as weakly-interacting massive particles. IMO, the Big Bang's biggest puzzle is what happened at its beginning, in the quantum-gravity epoch. But this is because we lack a successful theory of quantum gravity.
Now, wouldn't it be simply awful if physicists came to the end of physics and had no other questions to ask. (Fat chance!)
Perhaps Superstring Theory will be able to find some of those answers (at least mathematically, since we shall never be able to observe anything at that scale).
Incidentally, I just purchased a large number of Feynman lecture tapes to be added to so many that I already own (and I think that more are in the offing). The tapes are sold by WWW.SCIENCENEWSBOOKS.ORG, and the final box of six tapes (#14) is: "Feynman on Electricity and Magnetism, Part 1"! Obviously, there will be a Part 2, and so on. Each box of six tapes costs $40.00, and lasts approximately 8 hours, so there is a hefty amount of time that will be spent listening to one of my favorite physicists. Of course, I never had to suffer the slings and arrows of his outrageous disapproval of lectures by other (possibly) less capable scientists (from what I have heard from physicists who witnessed his behavior first hand).
But that is hearsay and probably was deserved by the recipients. But that is only conjecture and is possibly false.
Anyway, you always make good scientific sense.
ljbrs  
"Nothing is more damaging to a new truth than an old error." Goethe
Edited by - ljbrs on 01/02/2002 20:23:05 |
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