Narrowing Hubble's Constant - 8 year study concludes

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Discussion Overview

The discussion revolves around the Hubble Constant and its historical refinement, particularly focusing on an 8-year study led by Wendy Freedman. Participants explore the implications of this research within the broader context of cosmology, including debates about the validity of the Big Bang theory and the nature of scientific inquiry in this field.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants highlight the significance of Wendy Freedman's study in advancing precision cosmology and its role in the 1998 revelations about accelerated expansion.
  • Others question the scientific validity of the Big Bang theory, suggesting that the observed redshift could be explained by alternative mechanisms that do not require an expanding universe.
  • A participant raises concerns about the peer-review process potentially stifling dissenting views, particularly regarding the assumption of universal expansion.
  • There is a discussion about the nature of scientific proof and falsification, with some arguing that proof is not applicable in the same way as in mathematics.
  • One participant asserts that while cosmology has made significant progress, there remains uncertainty about events prior to the cosmic microwave background (CMB) radiation.

Areas of Agreement / Disagreement

Participants express a mix of agreement and disagreement, particularly regarding the interpretation of evidence for the Big Bang theory and the implications of redshift. There is no consensus on the validity of the current cosmological models or the nature of scientific inquiry in this context.

Contextual Notes

Limitations include unresolved assumptions about the mechanisms behind redshift, the dependence on prevailing theories, and the challenges of publishing alternative models in the face of established consensus.

Chaos' lil bro Order
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This is a nice little article on the history of the Hubble Constant and its refinement over time. There is also a summary of the 8 year Cepheid Variable study headed by Wendy Freedman of the Carnegie Observatory in it, in which they try to narrow down the limits of the Hubble Constant via 100s of Cepheid Variable observations. A nice little read.

http://physicsworld.com/cws/article/print/1036
 
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Nice article, dated July 1, 1999. Just about exactly 9 years ago.
Wendy Freedman's project (Hubble Key Project) ushered in an age of precision cosmology.
It was a major part of the revolution in cosmology that occurred in 1998, with not only Freedman's group narrowing down the Hubble parameter but also the reports of accelerated expansion. Cosmology became an exact observational science, not guessing game.

We are in the wake of those 1998 events.
 
marcus said:
[...] but also the reports of accelerated expansion. Cosmology became an exact observational science, not guessing game.
But is this "science" scientific in Popperian sense?

If the "BB theory" predicted decelerating expansion of the universe (due to "Einstein's biggest blunder") and it has turned out that the expansion is accelerating and Einstein was right plugging the cosmological constant into his equations, how do we know that the universe is expanding at all and it is not just another false assumption of the "BB theory"? We don't see the expansion just the redshift and know that it is assumed by the astronomers to be caused by the expansion.

But how do we know it is a right assumption? Only because the astronomers can't figure out nothing better as the reason for the redshift? But the "BB theory" already dismissed cosmological constant (that turned out to be needed) and with it the whole idea of "Einstein's (stationary) universe", which may turn out not to be a blunder neither. Someone may suddenly discover that in general realtivity there must be the observed amount of redshift in stationary space. Then what? It couldn't be even published because it would be "against the present consesus of astronomers" (who may happen not to believe in general relativity since they do quite well with the Newtonian gravitation and in the Newtonian gravitation it is the only way).
 
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JimJast said:
It couldn't be even published because it would be "against the present consesus of astronomers" (who may happen not to believe in general relativity since they do quite well with the Newtonian gravitation and in the Newtonian gravitation it is the only way).

Your reasoning being sound, your logic not flawed, your mathematical proofs being rigorous; you truly have nothing to fear. The problem arises when one is convinced of the above, yet can not see the flaws that others may point out.

The peer-review process is one of the more noble systems in human society.
 
robertm said:
Your reasoning being sound, your logic not flawed, your mathematical proofs being rigorous; you truly have nothing to fear. The problem arises when one is convinced of the above, yet can not see the flaws that others may point out.

The peer-review process is one of the more noble systems in human society.

But in the case of the BB, if all the peers believe the universe is expanding and only they can't prove it (because it's not possible to prove that the reason for the redshift is as the BB assumes, and a lot of evidence is still no proof) but you can falsify the expansion (which is rather easy, as it maby be done by just pointing to a necessary mechanism for the redshift and show that it produces the same redshift yet without the expansion)? Then you end up with no knowledge why you can't be published because peers (referees) don't see any flaws in your stuff but you still can't be published since your peers believe there must be an error "somewhere".
 
JimJast said:
But in the case of the BB, if all the peers believe the universe is expanding
Fortunately, this is not the case.

Goodness, some of the peers don't, it seems, even "believe" that GR is the last word concerning gravity!
and only they can't prove it
Fortunately, the peers are doing science, not mathematics (so "proof" is irrelevant).
(because it's not possible to prove that the reason for the redshift is as the BB assumes, and a lot of evidence is still no proof)
Thereby neatly proving (!) that proof is not possible in science (or at least astrophysics).
but you can falsify the expansion (which is rather easy, as it maby be done by just pointing to a necessary mechanism for the redshift and show that it produces the same redshift yet without the expansion)?
Well, write up this "necessary mechanism" and submit it to PF's IR section.

Oh, and be sure to be prepared for this alternative mechanism to be examined closely, to see that it 'works' everywhere and everywhen (and that there are no fatal inconsistencies more broadly).

Until there is such a mechanism on the table ...
Then you end up with no knowledge why you can't be published because peers (referees) don't see any flaws in your stuff but you still can't be published since your peers believe there must be an error "somewhere".
Fortunately, modern cosmology is not a religion.

But let's stick with your paradigm and see if we can falsify the idea expressed in the post of yours I am quoting.

A powerful falsification would be a paper, published in one of these peer-reviewed journals, presenting a cosmology in which the universe is not expanding, right?

Now if that's all that's required, your idea is so easily falsified that it's funny ...

Who wants to go first, with a reference to such a paper?
 
I do not think anyone is claiming the BB is an exact science. I think its fair to say that cosmologists haven't the the foggiest about what occurred before the CMB's creation, 380,000 after the BB. But I think cosmology is a very serious science now that Hubble and COBE and the WMAP surveys brought us so much data that they can now form plausible theories based on real evidence. Can string theory make such a claim?
 

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