George, thanks for the calm reply. Such replies make this board fairly unique, and that's one of its enduring characteristics.

In that we agree, and I just took a bit of exception when you said you appreciated the BA's action in banning JS. The BA said he hated doing it, and he's not alone there.

Me too. I'm just a piano player, a watercolorist, and an avid reader of books about science - the more recent, the better.

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Everyone is entitled to his own opinion, but not his own facts.

Note that the link above will download the PDF paper, about 96 Kbytes.

Thanks for the reference, I downloaded & read the paper. I am actually quite amazed at the idea that this paper was written (evidently) by physics department faculty. The flaws are very elementary, and should have been obvious even to a first year physics student.

To explain why I say this, let me point out two important formulae concerning blackbody radiation. They are the Stefan-Boltzmann Law and Plank's Radiation Formula (follow the links to see the equations and examine the physics).

The Stefan-Boltzmann Law allows one to compute the total power radiated by a blackbody at a given temperature. One can also solve the equation backwards; given a total power, one can derive the temperature that a blackbody would need to have, in order to radiate that much power. This is commonly called the effective blackbody temperature, acknowledging the fact that the source of energy could be far from a blackbody.

The Planck Radiation Formula is more complicated, because it describes the spectral energy distribution of the radiation from a blackbody at a given temperature. In other words, it describes the energy as a function of wavelength or frequency. If you integrate Planck's formula over all wavelengths (or frequencies), you get the power that shows up in the Stefan-Boltzmann law.

Now, according to the paper both Gillaume (in 1896) and Eddington (in 1926), predicted the cosmic background. That is clearly not true, because both used the Stefan-Boltzmann law to compute the effective blackbody temperature, the temperature that a blackbody would have were it to radiate the total energy in the background starlight. But as Eddington points out (in the paragraph after the one that is qouted in the paper), the starlight is not in thermodynamic equilibrium. Neither Guillaume nor Eddington mentions Planck's formula. I don't think that Guillaume mentions the spectral energy distribution, but Eddington does, in making the point that his temperature is an effective blackbody temperature (Eddington's words), and that the background is not in thermodynamic equilibrium (which Eddington certainly knew meant that it could not have a blackbody spectrum).

So far as I can tell, the discussion of Regener & Nernst concerns cosmic ray energies, and is not relevant to cosmic microwave background.

Born's temperature is, as far as I can tell, a kinetic temperature of the scattering medium that produces the redshift in Finlay-Freundlich's tired light redshift model. I don't see the connection to a background radiation field here either.

The fact appears to me that there has never been any prediction of the cosmic background temperature to match the big bang prediction, from any static model. And none were presented in the paper by Assis & Neves. They did not reference any predictions concerning the spectrum of the background radiation, and that's the real point of alluding to the success of the big bang in predicting the cosmic background temperature. Here the point is that the CMB spectrum is the most precise fit to Planck's formula ever seen, including laboratory black body experiments. That was the key prediction of big bang cosmology.

Competing cosmologies can produce thermal background, but only as a special case, or as an improbable event. But only big bang cosmology requires that the spectrum of the background radiation conform to Planck's formula.

So why isn't this in "against the mainstream"?

That is cute but that is not what the first estimate about the background radiation have expected originally.

http://www.geocities.com/kingvegeta80/BBT.html
Quote
"Original estimates on the CMB's temperature ranged from 20°K (est. by George Gamow) to 30°K (est. by Jim Peebles). The Stefan/Boltzmann law states that the amount of energy in a blackbody radiation field is proportional to its temperature to the fourth power (see the appendix). So here we have estimated energy output amounts as follows, which is measured in watts per square metre:
Gamow est.: 20°K4= 9 x 10-3 Watts/m2
Peebles est.: 30°K4= 4.6 x 10-2 Watts/m2
Actual temp.: 2.7°K4 = 3.01 x 10-6 Watts/m2


So we now have the original estimates of having anywhere from about 3000 to over 15,000 times energy than what is actually observed. Even Robert Dicke claimed that his group had estimated a temperature of 10°K, but that still yields just over 188 times what is actually observed. The observed temperature indicates a much more diffuse universe as was previously thought, ruling out the oscillating universe model. Ironically, non-expanding universe models predicted the 3 °K background radiation long before Penzias and Wilson discovered it (there is a link to a paper on this on Vincent Sauvé's page).
Edited to add this link
http://www.dfi.uem.br/~macedane/history_of_2.7k.html

The temperature is only an immediate problem for a closed (esp. oscillating) BB universe, but still also poses major problems for other high-Omega value scenarios, including the flat (Ω=1) universe scenario that is the most widely accepted. The real problem is the smoothness of the CMB. It is something that greatly contradicts original estimates. Irregularities in the CMB are supposed to reflect clumps in the early universe that would later condense into structures like galaxies. Original observations showed that it was completely smooth, but this later turned out not to be the case. When the COBE (Cosmic Background Explorer) satellite was deployed in November of 1989, it carried instruments to analyze the CMB. It has since detected anisotropies of one part in 100,000. The CMB was once again headline news, with some headlines calling it "the most important discovery of all time" and other even more gratuitous praises. However, even these irregularities were too small. The original estimates of anisotropy (made throughout the 1970s) required fluctuations of about one part in 1000--a hundred times more irregular than what is actually observed--to form even small structures like galaxies (that's not including clusters and superclusters, see below). These all indicate a universe way too diffuse to comply with the BBT."

I don't know too much about Neves but Andre Assis for sure is a pretty decent physicist. He's written tons of articles and several books.
http://www.ifi.unicamp.br/~assis/
Of course, his views are towards the static model side, so may not appeal to a wide audience.

Yes, I'm familiar with the objection that static models don't predict the smooth blackbody spectrum. It has been discussed in several recent threads. I don't wish to downplay this too much, but for me the more important thing is that static models do predict the temperature of space reasonably well. As Orion points out, the predictions of energy density by the BB were way off in comparison.

The biggest problem for static models is not in predicting the CMBR spectrum, but rather that there is still not a redshift mechanism that everyone can sign on to. My view is that once we have the redshift mechanism, some of the other problems, like the CMBR spectrum and time dilation in SNe, will come out at the same time. For static modellers, though, these sorts of problems can serve as useful clues to the nature of the solution.

The authors point out that both Guillaume and Eddington were using stars from the Milky Way only, the existence of external galaxies being unproved yet at that time. These observations can be seen to be of mainly historical interest.

Will have to check on this further. In the meantime here is a paper on Nernst's work which could be of interest.
http://redshift.vif.com/JournalFiles...F/V02N3INT.PDF

No, there is a connection, but it's all to do with Finlay-Freundlich's model. In this case it is actually the photons of the CMBR which are causing the cosmological redshift. In higher temperature regimes, the redshifts are higher. I don't know if Finlay-Freundlich's model was ever ruled out. Something else to check up on!

I think the temperature predictions were accurate enough. As you say, though, the spectrum is another thing. But I don't think they set out to prove that the spectrum business was settled.

There is another argument to show that static models can account for the CMBR temperature. If we take the average rate of input of stellar radiation into space, over a sufficiently large volume of space, we find that it equals the rate at which energy is lost from the CMBR due to redshift in the CMBR photons. This shows at minimum that there is an energy balance in a static model. The BB can't explain this. Here's a ref where this is discussed:
http://redshift.vif.com/JournalFiles...F/v05n3edw.pdf

But as I say, once we get the redshift mechanism we'll have the CMBR spectrum explained too.
George started the thread in a pro-BB format. We can continue this in the ATM forum if you'd prefer.

I appreciate your comments. Wish I could play piano. I took up electric guitar several years ago and I am enjoying it.

What do you think of the "bullet list" (currently revised edition - see original post)?

I am considering a second complimentary paraphrased list, Robin Williams' style, to help explain them but I mainly want a quick outlined version that I can memorize for reference. Should I do so?

Anyone think entropy should be a bullet????

Is there any evidence to support that a process could create negative entropy for the universe? No fair dumping any wastes outside our known universe (at least until evidence supports an alternative). I always liked the rephrased second law...."heat won't go from a cooler to a hotter, you can try if you like but you far better notter"!

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Lighten up! This is a stellar board!

I'm currently reading "The last three minutes" by Paul Davies, and he seems to think that entropy is fatal problem for static models. So maybe this could be a bullet.

No, Ari, it's just another Big Bang blank. In a static model, we must suppose that redshifted radiation is ultimately recycled into another form of energy. While diferent possibilities can be imagined here, the most likely one in my view is that redshifted EM radiation is converted to a different form of EM radiation which induces gravitation. Bodies have more entropy when they are widely dispersed in space, so when gravity draws them nearer to one another their entropy decreases. Thus the increase in entropy due to redshift is exactly balanced by a decrease in entropy due to more gravitation. This is actually a great benefit of the static model over the BB, as we can do away with notions like "heat death of the universe", etc.

Yes, I think of this same way as you. But this was supposed to be from the Big Bang point of view, so maybe we allow this to be at least a squirt of a water pistol?

Discussing cosmological models is not like discussing the latest movies. It's not about what appeals to one person and not another. It's about what fits the observations and what doesn't. Personal taste and preference is not an issue in science.

And the distances to the galaxies that Hubble derived using Cepheid variable stars were all underestimated by four to eight times. (Fortunately, they were all underestimated in the same proportion, so the fundamental Hubble relation remains valid.) But so what? I see nothing odd about early estimates requiring significant refinement, especially in astronomy. Meanwhile, you're just sweeping the requirement for a smooth blackbody spectrum under the rug? Cosmological models should agree with ALL the observations, not just specific ones you choose to consider.
Now, there is an extreme case of wishful thinking.
Was there something wrong with the redshift mechanism that is accepted by 99.44% of the astronomical community? Don't you realize that you are starting with a particular conclusion that for some reason "appeals" to you (a static universe), and then you are attempting to construct observations and interpretations of observations that will support your preconceived conclusion? In comparison, look at Hubble's example again. For nearly a decade he gathered data on the distances to the galaxies. Then he noticed the remarkable relationship between the measured distance and the measured spectral shift. His method is just the opposite of yours.
In other words, "If we want this preconceived conclusion, we must change what we observe." Not only is this Bad Science, it's Backward Science.

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Everyone is entitled to his own opinion, but not his own facts.

Tim Thompson claim this
So it seem than the earlier estimate were Not Based on the Planck`s spectrum formula.Can we suppose than this correlation was determined AFTER the datas were collected and analysed.Contrary to the claims made by TT?

Why does it seem so? I expect you're wrong. There were quite a few other parameters involved in the calculation, any one of which could introduce error.
I don't know how Gamow's early estimate was calculated, but the logic goes, "If there was a hot big bang, then the residual radiation would exhibit the characteristics of a perfect blackbody curve because at the time such energy was emitted, the universe would have been in nearly perfect thermal equilibrium." Certainly this was known before any data was collected. The fact that we can now measure background radiation exhibiting the characteristics of a perfect blackbody curve does not prove there was a hot big bang, but it provides very convincing and compelling evidence.

And I would suggest that anyone contradicting claims made by TT does so at the peril of their credibility.

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Everyone is entitled to his own opinion, but not his own facts.

The discrepency from the earlier estimations is the proof than the Plank`s spectrum was not the basis for the calculations.
Quote
"Original estimates on the CMB's temperature ranged from 20°K (est. by George Gamow) to 30°K (est. by Jim Peebles). The Stefan/Boltzmann law states that the amount of energy in a blackbody radiation field is proportional to its temperature to the fourth power (see the appendix). So here we have estimated energy output amounts as follows, which is measured in watts per square metre:
Gamow est.: 20°K4= 9 x 10-3 Watts/m2
Peebles est.: 30°K4= 4.6 x 10-2 Watts/m2
Actual temp.: 2.7°K4 = 3.01 x 10-6 Watts/m2

So we now have the original estimates of having anywhere from about 3000 to over 15,000 times energy than what is actually observed. Even Robert Dicke claimed that his group had estimated a temperature of 10°K, but that still yields just over 188 times what is actually observed.

In most everyday science what you say is true. When a biochemist proves a specific pathway, for instance, there is little place for personal taste. But many of the big questions in science are ones where getting definitive proof is a lot harder. It will be hard to prove that the origins of life happened in a particular way. We can only aim for a 'most likely' scenario. I think this is true in cosmology as well. How can we really hope to prove that the cosmos originated in a specific way? Most astronomers think the BB is true, but I think the majority would also admit it is just a model. There is room for alternative views, just as in the origins of life debate. I like Assis' view.

I'm not sweeping it under the rug. I'm just saying the precise explanation for the blackbody spectrum in the CMBR may not be at hand yet. Recall that it took a while for the mainstream to come up with an explanation for the smoothness of the CMBR, namely inflation. I trust that when the static side gets its explanation, it will not be so ad hoc in nature.
It is better to go from observation towards conclusions, and not the other way. But looking at your specific example, Hubble himself was not sold on the redshifts as being velocity shifts. It was others who took this observation and went to what I would say is the wrong conclusion.
No, we observe the same things, we just interpret them differently.

Translation: "This finding contradicts my view, therefore I'm just going to hope that the finding is shown to be wrong in the future. Of course, there's no foundation for such hope, but like I said, I just don't want to accept the finding."
Inflation is not an explanation for the smoothness of the CMBR. If you review Weinberg's 1977 The First Three Minutes, you'll find no mention of inflation. But there's a full chapter devoted to the CMBR.

And hopefully it will be better informed than your previous comment.

I didn't say he was. That's irrelevant to my point anyway.

Based solely on.... your personal preference that there be some other conclusion?

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Everyone is entitled to his own opinion, but not his own facts.

The CMBR temperature is dependent on the age of the universe and its baryonic density, neither of which were known to great accuracy at the time. Arguing over a temperature that's within an order of magnitude is a sideshow. The real issue is that no steady state theory has come up with a convincing explanation why the CMBR is such a perfect black-body. That's something the Big Bang Theory and only the Big Bang Theory predicted.

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Everything I need to know I learned through Googling.

theoricians working outside the Big Bang model were able to do a better job in their prediction with the datas available.I will let you comment their conclusions from the page I quote.
http://www.dfi.uem.br/~macedane/history_of_2.7k.html
No the real issue is the claim made by Tim Thompson
I stand on my position than the Planck's formula was not the basis used by the Big Bangers for the earlier estimation of the CMBR but than the correlation was made AFTER the datas were collected and analysed.

[quote="Orion38"]theoricians working outside the Big Bang model were able to do a better job in their prediction with the datas available.I will let you comment their conclusions from the page I quote.
http://www.dfi.uem.br/~macedane/history_of_2.7k.html
Once again, the temperature is not the key issue. The curve is. Neither Guillaume nor Eddington predicted a black-body curve. That being given, none of the ensuing claims are relevant.

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Everything I need to know I learned through Googling.

Can you give the reference... Who is the Big Bang theorician who have predicted a black-body curve for the CMBR before it`s effective discovery?
What is the date of publication?

Edited
Why the temperature for the predicted black-body curve was so different than the observations have reported?

And (I repeat)theoricians working outside the Big Bang model were able to do a better job in their temperature prediction with the datas available at the time.

The paper I have to hand is

"The Physics of the Expanding Universe," George Gamow, Vistas in Astronomy 2, 1726-32 [1956]

which predicts a 6 degree background. However, I have to admit that I haven't worked the calculations through in detail to confirm that this is supposed to be a black body.

Because some of the causal parameters, like the age of the universe and the amount of baryonic matter, were not known at the time. In particular, a younger universe (which seemed to be the belief at the time) yields a higher value for the CMBR.

Imagine that we are both at a train station. I predict that an Amtrak train is going to show up at 5 pm. You make a separate prediction that a commuter train will show up at 5.05 pm. Now, no commuter train shows up, but the Amtrak train arrives at 5.04 pm. Who has made the more accurate prediction? I would say that I did. Even if I'm off on the time, my prediction is closer to the character of what appeared.

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Everything I need to know I learned through Googling.

I think you should look for a new translator! There's nothing incorrect about having a model and waiting for new data to either support parts of it, rule out other parts, or point to new directions for the model. The BB has done that in spades. There are lots of areas where the BB is in conflict with the data, even as we speak.
That's true. The "smoothness problem" for the BB came later, when the CMBR was found to be too even to have allowed for initial galaxy formation. I was just using that as an analogy. I read Weinberg's book a long time ago, and it still sits on my desk as a constant reminder of how far astronomy has gone off the rails. I will have another look at it, to see how it relates to what Orion is saying.

Hardly. You're saying it's best to go from observations to deductions, and that's true. But think about Hubble's observation. It was not that the galaxies are receding, as I think you might say, but only that there was a distance-redshift relation. Many people think Hubble saw the expansion, but they're wrong. They interpreted Hubble's observation in the way they saw fit.

No, right from the start there were alternative explanations. Zwicky's was the first. Zwicky thought the redshift was due to a gravitational interaction of light with the matter along its route. And there are still many alternative explanations coming out each year.

But the BB is no more established than static models. We've seen in this very thread that there is no single piece of evidence which conclusively points to BB. At the same time, the BB proponents have ignored some key things, like the disappearance of physics, time, and the universe as we know it when we look bact to t = 0.

So still No confirmation than the black-body curve was predicted by Big Bang theoricians before its effective discovery.

Yes, but the theoricians using other parameters than the Big Bang arrive with better result in particular parameter based on the models of a Universe in dynamical equilibrium predicted its value before Gamow and with better accuracy.
You have a missing parameter in your analogy. because you have not predicted the Heat of the train engine at is arrival whatever if the train is right on the time scheduled or not.

The time in my example is the analog of the temperature. The point I was trying to make is that it doesn't matter if you get the time (or the temperature) right if the meaning of the time or the temperature differs between the prediction and the reality.

I agree, however, that there needs to be evidence that the pro-BB camp predicted the black-body curve ahead of time. Unfortunately, my physics and math are a little too rusty to be able to verify this without an effort.

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Everything I need to know I learned through Googling.

Thank you for clarifying this, ToSeek. Unfortunately, Orion doesn't seem to like your clarification for some reason, even though it's pretty much right on the money.

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Everyone is entitled to his own opinion, but not his own facts.

The prediction is inherent in the big bang theory. If there was a big bang, there must have been a time when the universe was in thermal equilibrium. Period. No big bang theorist needed to publish this obvious fact.
Your linked page doesn't work. Every page I've looked at about the history of the CMBR says Gamow's estimate was 5 K. This is not "so different" than the observations. It is extremely close. As ToSeek has said numerous times, the estimate is strongly dependent on the age of the universe. Until recently, the universe's age was very inexactly known. Many estimates simply put it at 10 to 20 billion years. That's not very exact, now, is it? So imagine what Gamow was working with in 1948.
I think ToSeek's analogy is quite good. Basically, they were lucky. Their data was not exact enough to get an exact answer either. They came close to the right answer, but for the wrong reason. If you want to review their detailed logic, bring it on. In their case, the temperature of the background radiation is determined from a completely different set of parameters (since they assume the universe is eternal). But again, there's no reason that their background radiation should conform to a blackbody curve. Indeed, there's not even any known mechanism to allow it to conform to a blackbody. Their radiation is not generated by a blackbody. Temperature prediction or no, they cannot explain why the radiation is observed to conform to a perfect blackbody curve. In the big bang theory, the theory itself demands the background radiation conform to a blackbody curve. When this observation was confirmed to high accuracy, most scientists throughout the world agreed that the big bang was the theory that was on the right track while the static universe theory was clearly NOT on the right track. Why are you and ExpErdMan so adamant about swimming against the tide of the entire world scientific community?

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Everyone is entitled to his own opinion, but not his own facts.

I understand the clarification made by ToSeek, the point in litige is if really the Big Bang theoricians have predicted a black- body curve before its discovery.
Read ToSeek previous post

I'm talking about Nobel-prize-winning Steven Weinberg, not Wilbur Weinberg from Portsmouth High School! Steve gives a remarkably rigorous treatment for a popular book. You like rigor, don't you?

None of which have stood up to scrutiny. But you're welcome to keep rolling that boulder uphill if that's what makes you happy.
What rock have you been hiding under for the last 50 years? The big bang theory is WAY more established than ANY alternative cosmology. As Chris Hillman says, "The observational evidence for the standard hot Big Bang theory of cosmology is overwhelming, again, so much so that this theory doesn't have any scientifically credible competitors anymore."

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Everyone is entitled to his own opinion, but not his own facts.

I repeat: The blackbody prediction is inherent in the big bang theory. If there was a big bang, there must have been a time when the universe was in thermal equilibrium. Period. No big bang theorist needed to publish this obvious fact.

I think ToSeek was essentially fooled by your direct question. I just read ten university webpages referring to the big bang's prediction that the background radiation should conform to a blackbody curve. Not one page mentioned any particular scientist who claimed this prediction. It then occurred to me that a "prediction" need not come from an individual scientist or be published at some particular time. As I said, the blackbody prediction is part of the theory itself. It is inherent in the theory. Your question is just wrong, misleading, and irrelevant. It's not who predicted the blackbody requirement. The theory itself predicts it because the theory cannot have it any other way.

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Everyone is entitled to his own opinion, but not his own facts.

Hmmm ,my intention was not to misleading but to find a citation from Gamov looking like this:-our calculations leads us to predict than the CMBR will be associated to a perfect black-body curve.-It seem rather than they said: "we expect to find a (temperature) remnant from the earlier universe ie -when the Universe was more hot and small- we expect a temperature to be..."

The reason you will (likely) not find such a quote is that George didn't want other scientists replying, "DUH! Of course any residual radiation from a big bang would conform to a perfect blackbody curve. That's obvious!"

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Everyone is entitled to his own opinion, but not his own facts.

Edited (rephrasing for clarity).
That is exactly the notion than they have predicted a PERFECT blackbody curve than I doubt.
Of course based on the temperature expected from 6K to 50K they have speculated than the CMBR will show a black- body curve.
Do you means than any blackbody curve is always expected to be perfect?