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Author Topic:   No Big Bang--Just gentle whisper
GDR
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Posts: 6202
From: Sidney, BC, Canada
Joined: 05-22-2005
Member Rating: 1.9


Message 31 of 100 (360183)
10-31-2006 4:20 PM


For the record Percy threads like this are helpful for those like myself who come here to learn. Thanks for the opportunity.

Everybody is entitled to my opinion.

  
Son Goku
Inactive Member


Message 32 of 100 (362142)
11-06-2006 12:01 PM
Reply to: Message 23 by nwr
10-30-2006 12:32 PM


Re: Back to the drawing board
nwr writes:
That said, I am still myself a bit of a skeptic regarding BB. That's mainly because I don't think there is yet enough evidence.
Which version of the Big Bang do you remain skeptical of?
I understand some versions are still a bit too unsupported for some/most people.
For instance would you think that the statement "The universe has been expanding for the last 12 billion years" is well enough supported.

This message is a reply to:
 Message 23 by nwr, posted 10-30-2006 12:32 PM nwr has replied

Replies to this message:
 Message 33 by nwr, posted 11-06-2006 12:54 PM Son Goku has replied

  
nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 33 of 100 (362152)
11-06-2006 12:54 PM
Reply to: Message 32 by Son Goku
11-06-2006 12:01 PM


Re: Back to the drawing board
There is oodles of evidence supporting a cosmological red shift.
The evidence that the cosmos is expanding, however, is far from satisfying.

This message is a reply to:
 Message 32 by Son Goku, posted 11-06-2006 12:01 PM Son Goku has replied

Replies to this message:
 Message 34 by Percy, posted 11-06-2006 1:06 PM nwr has replied
 Message 35 by Son Goku, posted 11-06-2006 1:32 PM nwr has seen this message but not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 34 of 100 (362159)
11-06-2006 1:06 PM
Reply to: Message 33 by nwr
11-06-2006 12:54 PM


Re: Back to the drawing board
nwr writes:
The evidence that the cosmos is expanding, however, is far from satisfying.
I think it would provide a wonderful counterpoint to Bob's approach if you'd elaborate on this so as to provide an example of the proper way to skeptically approach accepted scientific views.
--Percy

This message is a reply to:
 Message 33 by nwr, posted 11-06-2006 12:54 PM nwr has replied

Replies to this message:
 Message 36 by nwr, posted 11-06-2006 11:01 PM Percy has replied

  
Son Goku
Inactive Member


Message 35 of 100 (362167)
11-06-2006 1:32 PM
Reply to: Message 33 by nwr
11-06-2006 12:54 PM


Re: Back to the drawing board
nwr writes:
The evidence that the cosmos is expanding, however, is far from satisfying.
I see, it is the expansion itself, rather than conclusions drawn from expansion, that you think isn't well enough supported. Like Percy, I think it would be good to hear an exposition on flaws in current scientific theories.
Maybe not so much based around the evidence, but more so why this particular theory wouldn't reach your/ones acceptance quota.

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nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 36 of 100 (362296)
11-06-2006 11:01 PM
Reply to: Message 34 by Percy
11-06-2006 1:06 PM


BB skepticism
Okay, will do.
Let me first note that I have other things to do with my life than read the latest astronomy journals. So it is always possible that there is evidence out there that could convince me, but I haven't seen it.
A second note. I am not going around decrying the BB theory. I am not claiming that I can refute it. If I wanted to attack the theory, I really would have to read all of those astronomy journals.
With that said, here is my current position on the big bang:
The initial evidence for BB cosmology is the redshift. The amount of redshift depends on distance, as shown by Hubble.
Before discovery of the Hubble redshift, astronomers had been using shift in wavelength to measure whether a star is moving toward us or away from us. So it was natural to assume that the redshift indicates that the star or galaxy is receding (moving away from us). The original ideas of a Big Bang came from the conclusion that distant stars all appear to be receding, with the velocity of recession increasing with distance.
The relation between redshift and velocity of recession comes from the wave theory of light. As Percy often reminds us, all science is tentative, and the conclusion that distant objects are receding from us ought to be treated as tentative.
What we can surely conclude from the evidence, is that there is a cosmological redshift that correlates with distance. We can even give a formula relating the redshift to distance. But I hesitate before saying the redshift is due to recessional velocity. It could be that there is something we don't fully understand about electromagnetic waves, that explains the redshift. I'll note that the possibility has been considered and is usually referred to, somewhat disparagingly, as a tired light theory.
I'm not claiming that tired light theories are correct. My concern is that I don't believe they have been adequately disproved.
What about predictions from BB theory?
The prediction most often cited is that of CMBR (cosmic microwave background radiation). Okay, fine. However, in my opinion, you can predict some sort of CMBR based on the redshift alone. There is a classic Olber's paradox, why isn't the sky infinitely bright at night. The redshift explains Olber's paradox. But it implies that the energy that would otherwise make the sky infinitely bright, would instead be redshifted. The amount of redshift is such that the total energy would be finite, and we would reasonably expect most of it to be radio waves, such as in the microwave part of the spectrum.
Granted, the spectral distribution predicted for CMBR is different from that for a redshifted Olber paradox. However, most of the radiation in the redshifted Olber paradox would be obstructed by intervening objects. This would affect the spectral distribution. That makes it difficult to distinguish between the two explanations of the microwave background.
Here is my problem with BB. A simpler Hubble Redshift theory is more economical, and predicts much of what BB predicts. The more complex BB does make predictions that you could not make with the simpler theory. But most of those predictions are way beyond our ability to empirically test.
Thus, for the present, I retain my skepticism. I want to see clear empirical evidence that is independent of the redshift before I will go beyond that.

This message is a reply to:
 Message 34 by Percy, posted 11-06-2006 1:06 PM Percy has replied

Replies to this message:
 Message 37 by Son Goku, posted 11-07-2006 5:59 AM nwr has seen this message but not replied
 Message 38 by cavediver, posted 11-07-2006 6:23 AM nwr has replied
 Message 40 by Percy, posted 11-07-2006 7:12 AM nwr has replied
 Message 42 by baloneydetector#zero, posted 11-07-2006 12:05 PM nwr has seen this message but not replied

  
Son Goku
Inactive Member


Message 37 of 100 (362350)
11-07-2006 5:59 AM
Reply to: Message 36 by nwr
11-06-2006 11:01 PM


Very Good
Let me first note that I have other things to do with my life than read the latest astronomy journals. So it is always possible that there is evidence out there that could convince me, but I haven't seen it.
Don't worry, I think demanding you put that much effort into a forum post would be a bit unfair.
Anyway....
It could be that there is something we don't fully understand about electromagnetic waves, that explains the redshift. I'll note that the possibility has been considered and is usually referred to, somewhat disparagingly, as a tired light theory.
I don't take any particular issue with anything you wrote, but I'll just give a little exposition on this quote.
Electromagnetism is probably the best understood of the four forces, as the Quantum Mechanical theory describing it (Quantum Electrodynamics) is confirmed more than any other theory in science.
This doesn't really change your criticism, instead I would say that anything unknown with regard to redshift would be more likely to come from some interaction electromagnetic waves have with "X" (whatever X is) on their way to Earth, rather than something misunderstood about the waves themselves.
However this is a minor point.
Edited by Son Goku, : Slight spelling correction.

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Replies to this message:
 Message 39 by cavediver, posted 11-07-2006 6:24 AM Son Goku has replied

  
cavediver
Member (Idle past 3644 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 38 of 100 (362354)
11-07-2006 6:23 AM
Reply to: Message 36 by nwr
11-06-2006 11:01 PM


Re: BB skepticism
Hopefully I'll have time to do this justice later, but for now...
Here is my problem with BB. A simpler Hubble Redshift theory is more economical, and predicts much of what BB predicts.
Where does GR fit into your picture? It is conspicuous by its abscence in your post yet is pivotal to any (sensibly scientific) discussion of the BB.

This message is a reply to:
 Message 36 by nwr, posted 11-06-2006 11:01 PM nwr has replied

Replies to this message:
 Message 43 by nwr, posted 11-07-2006 12:17 PM cavediver has not replied

  
cavediver
Member (Idle past 3644 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 39 of 100 (362355)
11-07-2006 6:24 AM
Reply to: Message 37 by Son Goku
11-07-2006 5:59 AM


Re: Very Good
Hey, SG! Been a while... working on anything suitably on-topic for this thread?
And yes, I agree totally. E/M is unbelievably well understood across the universe as evidenced by for example the prediction of the value of the gyromagnetic ratio, by the predicted and observed astrophysical processes observed at opposite ends of the universe, etc.
Edited by cavediver, : No reason given.

This message is a reply to:
 Message 37 by Son Goku, posted 11-07-2006 5:59 AM Son Goku has replied

Replies to this message:
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Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 40 of 100 (362367)
11-07-2006 7:12 AM
Reply to: Message 36 by nwr
11-06-2006 11:01 PM


Re: BB skepticism
Hi Nwr,
Thanks much!!! That was great!!!
I'm going critique your questioning of BB theory for the benefit of creationists so that they have a rough idea of where I set the bar for challenging scientifically accepted theories.
nwr writes:
As Percy often reminds us, all science is tentative, and the conclusion that distant objects are receding from us ought to be treated as tentative.
But tentative doesn't mean questionable, and that's your implication. All science is tentative, and some of it is questionable, but all that is tentative is not questionable. In other words, you can't call a scientific theory into question simply because it is tentative. All scientific theories are tentative. You can certainly challenge any scientific theory since none represent timeless truths, but you can only deem them questionable by pointing to incompatible data or contradictory predictions and so forth.
The original ideas of a Big Bang came from the conclusion that distant stars all appear to be receding, with the velocity of recession increasing with distance.
This is just a terminology quibble since I think you actually intended to say galaxies, but anyway, while I think it is true that some stars in other galaxies are so bright as to be perceivable by us, for the most part it is entire galaxies for which we calculate red shift, not stars.
What we can surely conclude from the evidence, is that there is a cosmological redshift that correlates with distance. We can even give a formula relating the redshift to distance. But I hesitate before saying the redshift is due to recessional velocity.
We actually say much more than that the red shift is due to recessional velocity - we say that the recessional velocity is due to the expansion of space. Relativity tells us this is so.
It could be that there is something we don't fully understand about electromagnetic waves, that explains the redshift. I'll note that the possibility has been considered and is usually referred to, somewhat disparagingly, as a tired light theory.
There is no evidential support for tired light. Sylas participated in an excellent discussion with Lyndon Ashmore on the subject a while back: Tired Light
There is a classic Olber's paradox, why isn't the sky infinitely bright at night. The redshift explains Olber's paradox. But it implies that the energy that would otherwise make the sky infinitely bright, would instead be redshifted. The amount of redshift is such that the total energy would be finite, and we would reasonably expect most of it to be radio waves, such as in the microwave part of the spectrum.
I confess to being as capable as anyone of screwing up the explanation of why Olber's paradox isn't an issue, but I'll give it a try anyway. Olber's paradox applies to an infinite universe. While the universe may indeed be infinite, because of the expansion of space there is only a limited portion of it that we can actually perceive, since the rest of the universe is receding from us at speeds greater than that of light.
Granted, the spectral distribution predicted for CMBR is different from that for a redshifted Olber paradox. However, most of the radiation in the redshifted Olber paradox would be obstructed by intervening objects. This would affect the spectral distribution. That makes it difficult to distinguish between the two explanations of the microwave background.
Somewhere in the Tired Light thread it is described in detail by Sylas and Eta (a cosmologist) why the spectrum from tired light theory does not come close to resembling CMBR.
Here is my problem with BB. A simpler Hubble Redshift theory is more economical, and predicts much of what BB predicts. The more complex BB does make predictions that you could not make with the simpler theory. But most of those predictions are way beyond our ability to empirically test.
Let's see, you have the simple Hubble red shift theory that fails in some circumstances. Then you have the "more complex BB theory" that accurately addresses the same phenomena that the simpler theory fails, but because it makes predictions that we can't yet verify, indeed may in some cases never be able to verify, that's the theory you question.
Thus, for the present, I retain my skepticism. I want to see clear empirical evidence that is independent of the redshift before I will go beyond that.
I don't think you need to read any scientific journals to find evidence independent of the red shift, and you already mentioned one in the CMBR. The correspondences between variations in the CMBR and theories of how galaxies form is another independent confirmation. The proportion of elements in the universe as would have been produced in the BB is another confirmation.
I'd say your questioning of BB theory reads like one of the better creationist efforts, but as science it is lacking. You've questioned the theory without raising a single anomalous experimental result or failed prediction, and without offering any replacement.
I know I must seem ungracious and I apologize for that, because after all I did request that you do this and you came through wonderfully and in short order. But I have to cast the same critical eye at posts from friends as well as foes or have my objectivity questioned.
--Percy

This message is a reply to:
 Message 36 by nwr, posted 11-06-2006 11:01 PM nwr has replied

Replies to this message:
 Message 41 by nwr, posted 11-07-2006 11:59 AM Percy has replied

  
nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 41 of 100 (362412)
11-07-2006 11:59 AM
Reply to: Message 40 by Percy
11-07-2006 7:12 AM


Re: BB skepticism
But tentative doesn't mean questionable, and that's your implication.
If it is tentative, then it can be questioned. Indeed, it must be questioned. In that sense, it is questionable. To say that it could not be questioned would be to say that we have made it into a religion.
I suspect you were using "questionable" to mean "dubious". That's a different issued. Note that I am not spreading doubt about BB. I only posted my previous message because of your request. I only mentioned my skepticism in Message 23 to illustrate that there are more reasonable ways of being skeptical than those used by the originator of this thread.
I was reading an astronomy book a few years back. When it got to the discussion of dark matter, the author stated that one possible explanation is that our theories of gravity could be wrong. So the author thought that our theories of gravity were questionable (could be questioned), although he clearly did not consider them dubious.
I'd say your questioning of BB theory reads like one of the better creationist efforts, but as science it is lacking.
I did not present it as science. I presented it (at your request), to explain my personal doubt. Having personal doubt is not a "creationist effort". The creationists would not like my personal doubt of their religious doctrines.
Keep in mind that I am not asserting "BB is wrong." Rather, I am asserting that, for me, acceptance of BB would be premature.
I should add some perspective. I reject traditional scientific epistemology, and the base philosophical epistemology from which it derives. This rejection grows out of my investigation of human cognition. In particular, I disagree with the account of science you gave in Message 144. The "research programs" of Imre Lakatos are an improvement, though they too fall short as an account of science.

Regime change in Washington - midterm elections, Nov 7

This message is a reply to:
 Message 40 by Percy, posted 11-07-2006 7:12 AM Percy has replied

Replies to this message:
 Message 44 by Percy, posted 11-07-2006 2:20 PM nwr has replied

  
baloneydetector#zero
Inactive Member


Message 42 of 100 (362414)
11-07-2006 12:05 PM
Reply to: Message 36 by nwr
11-06-2006 11:01 PM


A very coherent response
One of the best responses that I've seen in a while. Very good

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nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 43 of 100 (362418)
11-07-2006 12:17 PM
Reply to: Message 38 by cavediver
11-07-2006 6:23 AM


Re: BB skepticism
Where does GR fit into your picture?
That's tentative too.
Newtonian mechanics doesn't quite work out for the cosmos as a whole. So I need to consider GR as currently the best alternative. Moreover, I need to build on top of GR, to reasonably understand the cosmos. Thus I tentatively accept GR.
I have no need to build on top of BB, so there is no necessity for me to tentatively accept it right now. Please recognize that this is a personal position. I expect that your work does build on top of BB, so I would expect you to have a different view.
--
Here's an analogy from mathematics, where AC (axiom of choice) and CH (continuum hypothesis) are held by some to be controversial. Yet both have about the same basis, in that both have been proved independent of the other axioms of set theory.
I have no problems with AC. Much of the mathematics I have done depends on AC, and we would be much the poorer if we were to abolish AC from mathematics. But I have found no great use for CH. Thus I can easily remain uncommitted with respect to CH, while committing myself to AC.

Regime change in Washington - midterm elections, Nov 7

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Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 44 of 100 (362447)
11-07-2006 2:20 PM
Reply to: Message 41 by nwr
11-07-2006 11:59 AM


Re: BB skepticism
nwr writes:
I only posted my previous message because of your request.
Yes, much appreciated! If you're up for it we could go at it on this topic, and maybe it'll turn out to be a positive example of good debate.
I suspect you were using "questionable" to mean "dubious".
Yes, exactly. All theories are tentative, so calling BB theory tentative does nothing to distinguish it, in terms of being dubious, from other theories. You have to identify what is deficient about BB theory that leads you to conclude that it is more deserving of challenge than other theories which are all also tentative.
I was reading an astronomy book a few years back. When it got to the discussion of dark matter, the author stated that one possible explanation is that our theories of gravity could be wrong. So the author thought that our theories of gravity were questionable (could be questioned), although he clearly did not consider them dubious.
All theories could be wrong and can be questioned - the theory of gravity is not special in this regard.
I already explained why the objections you listed before are inadequate, you didn't really say anything specific in reply, so bottom line: if you find BB theory dubious, why?
--Percy

This message is a reply to:
 Message 41 by nwr, posted 11-07-2006 11:59 AM nwr has replied

Replies to this message:
 Message 45 by nwr, posted 11-07-2006 3:26 PM Percy has replied

  
nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 45 of 100 (362456)
11-07-2006 3:26 PM
Reply to: Message 44 by Percy
11-07-2006 2:20 PM


Re: BB skepticism
I already explained why the objections you listed before are inadequate, ...
My objections are inadequate to persuade you. But I am not attempting to persuade you. It does not require any objections for me to decide for myself that I am not yet ready to commit to BB cosmology.
.. so bottom line: if you find BB theory dubious, why?
I have avoided saying that it is dubious.
Our scientific knowledge is mostly an extrapolation of what we can test in labs on earth. In the case of cosmology, it is a gross extrapolation. One always has to be careful about extrapolation. If our extrapolation indicates a singularity, it may be that there is an actual singularity. But it could also be that our extrapolation doesn't work - maybe the principles we are assuming don't extrapolate that far.
Even if there is a singularity, why does it have to be a "big bang"? Isn't it possible that we could be inside a large black hole, and what we see as a singularity is really the event horizon of the black hole, as seen from the inside? I mention this possibility to point out the difficulty of reaching conclusions when our extrapolation leads to a singularity.
Our ability to extrapolate depends on their being a high degree of regularity. That the extrapolation predicts a singularity is strong evidence that the assumed regularity is not there.
To be clear, I am not denying BB. I accept it as a possibility. But I do not currently find it sufficiently persuasive.

This message is a reply to:
 Message 44 by Percy, posted 11-07-2006 2:20 PM Percy has replied

Replies to this message:
 Message 46 by Son Goku, posted 11-07-2006 5:04 PM nwr has seen this message but not replied
 Message 49 by Percy, posted 11-07-2006 9:22 PM nwr has replied

  
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