JEROME - Life and Linear Time

[Wangler]

They've discovered the CBR, at exactly the temperature it was predicted to have.

Yes, exactly at the temperature it was predicted to have. Penzias and Wilson made their observation in 1965. Before that, I understand estimates for the "temperature of the universe" ranged from 50K (Gamow, 1948) to 5K (Herman, Alpher, 1948).

There were many, many predictions, with some persons (Gamow, for example) changing predictions a number of times, due to new observational evidence, or tweaks to their model.

So, I suppose that a observation of a 3K CBR is exactly at the predictions of 5K to 50K.

I suppose.

I choose to follow the evidence.

What about the evidence that speaks to a fundamental problem with the current cosmology paradigm?

Such as the evidentiary problems associated with Big Bang nucleosynthesis, especially regarding lithium?

 

[aggle-rithm]

Such as the evidentiary problems associated with Big Bang nucleosynthesis, especially regarding lithium?

I wasn't aware that the creation of lithium at the Big Bang was much of an issue. Doesn't it get created in stars?

 

[Wangler]

I wasn't aware that the creation of lithium at the Big Bang was much of an issue. Doesn't it get created in stars?

I apologize: my reference should have been to the primordial lithium abundance.

Sorry I did not make that clear.

 

[RecoveringYuppy]

OK, so what's your problem with primordial lithium?

 

[DeiRenDopa]

I apologize: my reference should have been to the primordial lithium abundance.

Sorry I did not make that clear.

Being pedantic ...

It's also the primordial ⁷Li abundance; the other stable isotope of Li (⁶Li) is expected to have a primordial abundance of zero.

It it important to note that, unlike D, ³He and ⁴He, the primordial abundance of ⁷Li is very difficult to estimate, not least because ⁷Li is so fragile.

 

[DeiRenDopa]

OK, so what's your problem with primordial lithium?

It's not his problem, it's one of the (very) few discrepant BBN datapoints ... the estimated abundance of primordial ⁷Li is several sigma from that expected, based on the estimated primordial abundance of D and He (estimated using ΛLCDM models with parameters that fit all the other data).

However, the estimated abundance of primordial ⁷Li is a conclusion which relies upon a quite long logic chain (albeit one built with components from standard astrophysics) with many parameters; if there important processes that create or destroy ⁷Li, in the objects in which it is observed (or their precursors), which have been mis-modelled (or not even modelled at all), then the estimates will be wrong.

 

[RecoveringYuppy]

Thanks DeiRenDopa, but are you sure that's going to be Wangler's objection?

 

[DeiRenDopa]

Thanks DeiRenDopa, but are you sure that's going to be Wangler's objection?

.
Based on his earlier post, pretty sure.

My guess is he's boning up on the material from an earlier 'alternative' conference (something about a crisis in cosmology), by reading some material compiled by those who dislike (or stronger) modern cosmology (for whatever combination of reasons). The 'BBT failed to predict the CMB temperature!', together with the content that followed, is pretty standard in such lists, and the discrepant primordial 7Li abundance comes close behind. The good news is that he is choosing well from such lists ... he leaves out much of the woo-ier material (like 'intrinsic redshifts'); the bad news is that I doubt he knows much about the 'BBT failures' he posts, beyond what's in 'BBT is wrong! WRONG!! WRONG!!!' compilations he's glossing.

But I could well be quite wrong ...

 

[Wangler]

Thanks DeiRenDopa, but are you sure that's going to be Wangler's objection?

DRD explained the point, and my position, well.

As DRD says, it is one of the very few discrepant BBN points.

 

[RecoveringYuppy]

So you were being sarcastic with "fundamental problem with the current cosmology paradigm"?

 

[Wangler]

.
Based on his earlier post, pretty sure.

My guess is he's boning up on the material from an earlier 'alternative' conference (something about a crisis in cosmology), by reading some material compiled by those who dislike (or stronger) modern cosmology (for whatever combination of reasons). The 'BBT failed to predict the CMB temperature!', together with the content that followed, is pretty standard in such lists, and the discrepant primordial 7Li abundance comes close behind. The good news is that he is choosing well from such lists ... he leaves out much of the woo-ier material (like 'intrinsic redshifts'); the bad news is that I doubt he knows much about the 'BBT failures' he posts, beyond what's in 'BBT is wrong! WRONG!! WRONG!!!' compilations he's glossing.

But I could well be quite wrong ...

DRD,

You not only pay attention to these myriad posts, but you also draw good conclusions from the post material.

Well done, sir!

The only very slight miss was that I found that "alternative cosmology conference" just in the last day, most of my other "mulling about" for contrarian points has been done since I have joined JREF earlier this year.

Now, I must freely confess that your bit of 'bad news' hits the nail on the head: I know very little about the 'BBT failures' that I post; I am trying to learn, though.

At this time, I usually must always concede to those on this forum who actually know the stuff, but perhaps that will change as I broaden my understanding.

The only reason I speak up, when not knowing some of this stuff 100%, is because I think that some presentations of standard theories are presented in a somewhat dogmatic manner.

Especially for a sceptics forum.

So, I chime in with my 1/2 cents worth at that point.

 

[Wangler]

So you were being sarcastic with "fundamental problem with the current cosmology paradigm"?

Well, being partly sarcastic is probably a fair assessment.

I think that there are problems with the current cosmology paradigm. I do lack the education and experience to claim unequivocally that they are 'fundamental'.

 

[Wangler]

.The 'BBT failed to predict the CMB temperature!', together with the content that followed, is pretty standard in such lists, and the discrepant primordial 7Li abundance comes close behind.

Just an example of the process leading me to the Li issue:

When I was reading another post, and the subject of the CMB spectrum came up, I was fascinated to learn all the things that the CMB spectrum could tell us....very cool.

That lead me looking for more information on CMB, and current cosmology observational tests.

It was in looking in one of these papers (I can't remember which), that they talked about the primorial abundances of H, He, Li as predicted by the BBT.

It was there I saw the Li problem; they also talked about the He problem, which apparently has improved somewhat recently.

I think that it is important to keep in mind that theories like the BBT, which does not match all observational evidence, is not as concrete as, say, General Relativity, which does match all observational evidence.

That is not to say that BBT is the wrong theory, it is just not the only theory.

Another example:

One thing I am trying to learn more about is the predictions on the matter density of the universe, and what leads us to the energy, DM, DE, and matter fractions that we hold to in the concordance LCDM theory.

Sure, I can listen to people tell me that it is the best theory we have, but I want to try to understand why.

I am sure to come across other reasonable (to this layman) objections to LCDM throughout this learning process, which I will not hesitate to bring to discussions here, if I think it would be useful.

Also:

There are many "alternative cosmology" websites out there. It can be hard to separate the wheat from the chaff. May just make claims, but there little or no trail for discovering the scientific rational behind the claims.

Some are better than others, obviously.

 

[Tubbythin]

Being pedantic ...

It's also the primordial ⁷Li abundance; the other stable isotope of Li (⁶Li) is expected to have a primordial abundance of zero.

That's not being pedantic. In nuclear physics the neutron number is as important as the proton number. Being vague about the neutron number creates as much of a problem as being vague about Z.

EDIT: How did the thumbs down symbol appear at the top? It wasn't deliberate.

 

[The Man]

EDIT: How did the thumbs down symbol appear at the top? It wasn't deliberate.

A mere slip of the finger as your cursor passed over that smilie activator. I had that happen before myself, the title smilie activators are located under the post reply dialog box and you can deactivate it in advanced editing.

ETA: Or maybe it was just a subconscious action?

 

[articulett]

Nominated.

It was fantastic.

Jerome is impenetrable so he cannot appreciate it. But the rest of us can.

 

[arthwollipot]

I apologize: my reference should have been to the primordial lithium abundance.

Sorry I did not make that clear.

Just out of interest, how can one tell the difference between primordial lithium and lithium that is manufactured through stellar nucleosynthesis?

 

[DeiRenDopa]

Just out of interest, how can one tell the difference between primordial lithium and lithium that is manufactured through stellar nucleosynthesis?

I'm not Wrangler, but I hope you won't mind me jumping in with a (very) brief answer ...

A: with considerable difficulty!

Not only is 7Li generated by BBN (Big Bang Nucleosynthesis), but it is also generated in stellar nucleosynthesis. However, it is also destroyed in stellar cores, so its observed abundance, due to this process, must come from somewhere else. There are several sources, such as flares, novae, and AGB stars; supernovae are also expected to produce some.

But wait! It gets more complicated!!

When a high energy particle collides with the nucleus of an atom such as C or O - which are not rare in the interstellar medium (ISM) - the products include 7Li. This process is called spallation, and as the ISM (and the IGM - inter-galactic medium) has plenty of high energy particles passing through it (they're called cosmic rays, or, rarely today, galactic cosmic rays), 7Li will be produced.

So, three+ sources, and two+ sinks (spallation also destroys 7Li).

However, the other stable Li isotope (6Li) is different: no BBN source, very small source in stars (flares), and prolific cosmic ray spallation source. Sinks are the same, except that for 6Li, destruction in stars is even more efficient than for 7Li.

The principal method of estimating primordial Li abundance is interpretation of the spectra of 'low metallicity stars' (stars with low abundances of 'metals'- astronomers call all elements other than H and He 'metals') - the 7Li in them is assumed to be primordial, once a correction for the contribution of ancient cosmic ray spallation is added (estimated from the abundance of 6Li in such stars) ... metal-poor stars are very old, they formed from gas which had been only slightly enriched with metals, from earlier generations of stars).

Needless to say, there is a great deal of astrophysics involved in this conclusion, not to mention the uncertainties of estimates of both 6Li and 7Li in the spectra of faint stars!

The logic chains, and the astrophysics, have been checked, tested, independently verified, etc, etc, etc six ways to Sunday, and the conclusions (concerning primordial 7Li abundance) seem to be quite consistent. However, given some of the uncertainties, it is premature to say the conclusions are robust (IMHO). For example, the ratio of 6Li to 7Li produced by cosmic ray spallation depends on several factors, and extrapolating from what today's cosmic ray energy spectrum is to that of the time when the old stars we observe were accumulating 6Li may be an extrapolation too far (IMHO).

 

[arthwollipot]

Thanks. That's really helpful...

I'll have to read it again when I'm less drunk.

 

[JEROME DA GNOME]

I'm a sycophant to the evidence. Yes, I admit it, I'll follow the evidence wherever it leads me, even if I find that place unsettling.

Thanks for an explaination of the theology of Big Bang.

But the evidence doesn't show any of these things. What it shows is that the Universe is 13.7 billion years old, started in an event called the Big Bang, has been expanding ever since, and may keep on expanding forever. It shows that stars are powered by nuclear fusion reactions caused by high pressures and temperatures in their cores. It shows that each generation of stars adds more and more heavy elements to the Universe, changing the chemical make-up of the next generation of stars.

Evidence that stars are powered by fusion? Did not think so.

So, one last time, I'm going to lay out the way in which the evidence for the Big Bang piled up.

I redacted the paragrph which was nothing but a history of the theology.

It is reasoned that if the Universe began as a tiny fireball then there should be a tell-tale radiation signature, a near perfect blackbody radiation curve at just a few degrees above absolute zero, called the Cosmic Background Radiation (CBR). Penzias and Wilson, while setting up their microwave antenna find a constant signal from all areas of the sky which they first mistake as being due to pigeon droppings in the feed horn of their antenna. After cleaning it out, and discovering that the signal is still there, they try numerous other ideas, until, in desperation they call a friend, hoping he might know what it is. He does, he was planning to set up a microwave antenna to look for it. They've discovered the CBR, at exactly the temperature it was predicted to have. By accident.

Please, what exactly was the prediction made by the BBT concering CBR?

Just stating that it was a correct prediction is nothing more than faith. You have yet to present eveidence, just story telling as to how the "evidence" was acquired.

Boomerang, a balloon borne microwave antenna, maps the CBR and shows it to have a near perfect blackbody curve. This is followed by COBE, a satellite that shows there are minute anisotropies in the CBR. Theory predicts this, since a perfectly smooth Big Bang would not have allowed the galaxies to form as they have. WMAP, the Wilkinson Microwave Anisotropy Probe shows the anisotropies in far more detail, obtaining a power spectrum which agrees to a very high degree with the predictions of theory.

What causes these anisotropies according to BBT? How are they consistent with BBT? Opps, they are not!

Nucleosynthesis, a field of physics made possible by relativity, shows that stars are powered by core nuclear fusion reactions, and even allows scientists to work out how much energy any given star is producing, and which nuclear reactions are happening in its core (actually, it's a little more complicated than that, but it all agrees with the theory). Particle physics predicts that the Sun's core nuclear fusion reactions should produce massive numbers of near massless particles called neutrinos which should be cascading through the Earth from the Sun. Neutrinos are discovered in exactly the amounts that theory predicts.

Would it not be detrimental for scientists in this field if the stars are not powered by fusion? Predictions sans evidence are nothing more than the beginings of science. Unless, are you aware of science experimentaly producing fusion?

Relativity makes other predictions - black holes, neutron stars, pulsars, time dilation, all of which have been evidenced, confirming the power of relativity, which is is the basis predicting the Big bang, which has also been evidenced in many different ways.

Have they been evidenced or has the evidence been made to fit?

The only initial premise in all of this is that the laws of physics are constant everywhere and everywhen, with the sole exception of the inside of a singularity (this is because the maths we have can't cope with such an extreme situation, not because it breaks the laws of physics). You might try to argue that the laws of physics aren't constant, but then you can't be sure of anything, and you might as well give up on astronomy completely.

The laws of physics and math are violated by the BBT. Here you are making the excuse that we just do not have the math and physics to explain it.

Can you think of any other scientific theory in which the laws of physics and math are discarded in this manner?

The evidence leads, inexorably, to the conclusion that the Universe started as a tiny fireball. What set that fireball off is completely unknown, and may be unknowable. But it's where the evidence leads. And that's where I follow.

No, BBT started with the premise that there was "In the Begining" a tiny fireball.

I choose to follow the evidence.

You did a lot of story telling and provided nothing in the way of Mountains of evidence.

I might as well read the bible and claim that it is evidence of what happened at "The Begining".