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Originally Posted by Michael Mozina
The point here is that the gas model is predicated on a "bang" that encompasses all the energy of the universe and releases all the matter in the universe. If the event was simply an interaction between two "fields of energy", that included suns and other forms of matter, then iron and heavy elements may have always been here.
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Er, no. The BBT is quite specific about the relationship between elements, stars, and time; an important part is that, in the early period (the specifics matter; I'm omitting them for now), the temperature was so high that elements could not exist. As the universe expanded, and cooled, baryons were created (they 'crystalised out'); later, as the temperature dropped, the baryons could combine into stable combinations, and (much, much later) stars were formed, in which those stable combos got re-jigged.
Of course, all kinds of things 'may have always been here', but, so far, no one has produced a self-consistent model of how this could happen; one that is also consistent with good observational and experimental results.
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The gas model theories that were around where I was in my teens have long been replaced by models that move the creation of iron further and futher backwards in time because of such findings.
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Well, this I find somewhat surprising! That models of decades ago didn't specifically address the abundance of 'metals' in the first ~100 million years after the end of the radiation era I wouldn't be at all surprised to learn; that metals could NOT be formed, in observable quantities, in the first billion years, in these models of yore, I would find surprising.
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The question then becomes: Is it scientifically sound to ASSUME a "bang" rather than "slam"? What evidence leads us to ASSUME that iron didn't predate the event?
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Hmm, OK; I'll bite.
Who 'ASSUMES' a "bang"? Isn't it more a case of 'a theory, incorporating a "bang", is particularly successful at accounting for good observational data AND is internally consistent AND is consistent with good theories derived from/based on Earth-bound good experimental results'?
Wrt to "slam": where's the theory? Absent anything other than vague word-pictures, what is there even to 'ASSUME'?
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Keep in mind that we are still using the "count the photons" method of counting atoms.
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Given your record of posts, here in BA/UT/BAUT, I am fairly sure you're not joking Michael. So, rather than leap in, boots first, let me simply ask: what methods or techniques, in particular, are you referring to here? From your perusal of popular techniques in astrophysics, what methods are used to estimate the mass of various atomic species (both relatively and absolutely)? How are data from 'counting photons' used to estimate 'abundances'?
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That is a dubious way to come up with percentages.
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Why? I mean, from what set of good observational or experimental results do you conclude that the estimated 'percentages' (including estimates of uncertainties) are 'dubious'?
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The interesting aspect of that percentage however is that it is not much different than measurements of our own sun using the same technique. In other words a heavily recycled sun is hardly much different in content than an early model of universe.
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Huh? Are you referring to the fact that the Sun is principally H and He (and little in the way of 'metals')? In what respect is this estimate inconsistent with (say) the estimated average density of the Sun?
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If the method is inaccurate in gleaning percentages it may still be damaging to the notion that iron was created after the BB.
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Indeed.
But surely the key question isn't 'may', but 'in what way' or 'by how much'?
IOW, doubt is a constant given in all of science, it's part of the air; real science is done when something different comes along, or something quantitative can be worked on.
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I'm not trying to build a case on press releases. There is evidence however that the gas model has problems, starting with the fact we have to keep changing the model's predictions every year.
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I don't understand this - are you referring to cosmology? or stellar evolution and structure?
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When I was a kid, it supposedly took 5 billion years for galaxies to form. Today we find they existed before a billion years had passed. Somehow all those "good" calculations and predictions of the past required a lot of adjustments to keep up with observational fact. That doesn't concern you a bit?
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Welcome to the world of modern science!
Personally, I'd be mighty concerned if, in such a young field as cosmology, things did NOT change over several decades!
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What evidence suggest s that iron did not predate the events of 0,0,0,0?
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Er, the CMBR, all the data from all the particle physics experiments of the past half dozen decades, the non-detection of relict neutrinos in Kamland, the power spectrum of galaxy and quasar density fluctuations, the abundance of D, H, He and Li in the ISM (and IGM), the SZE, ...