It seems to me that one of the primary reasons that hydrogen is presumed to be the most abundant element, and the primary reason that suns are presumed to be iron poor is because we ASSUME that all matter formed in the Big Bang. I'd like to question that most basic of assumptions for a moment.

If we assume based on telemetetry of galaxies that all matter was once concentrated NEAR a centralized location, how could we know that the events of 0,0,0,0 were not the result of the interaction of preexisting matter. In other words rather than going with the assumption that all matter was created in this event, the event may have looked more like a galaxy collision where some matter interacts violently and some does not.

There does seem to be a bias in astronomy today that leans toward the idea that all matter was created in the events of 0,0,0,0 but what quantitative and qualitative analysis favors a bang over a slam?

Consider the following:

http://news.bbc.co.uk/1/hi/sci/tech/2992313.stm
http://www.rednova.com/news/space/23...rse/index.html
http://www.spaceref.com/news/viewpr.html?pid=17525
http://chandra.harvard.edu/photo/2004/antennae/

Based on this information, how can we be sure that our universe was ever iron poor?

I only checked the first link.

When the articles says large amounts, it doesn't actually say anything about how large and is just quoting from the press release, which uses the words large amounts to mean much more than anticipated for so old QSO's, not high amounts as an absolute measurement.

I went directly to the original source, Freudlings Paper in the Astrophysical Journal, where it's clear in the conclusion that the iron amount they so surprisingly found was about as much as is on the sun. ie. below 1%.

This example alone should tell you how dangerous it is to try to draw conclusions based on what you read in the news.
It will have been rewritten at least twice, once for the press release, at least once more by a nonscientist for publication.

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You have it the wrong way around.

We think hydrogen is the most abundant because that is what we see. Then we try to explain where it comes from, and the big bang is a good explanation.

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if we consider that stars are not the only source of higher element nucleosynthesis. I would like to see some research on a coevolutionary model that explores quasar nucleosynthesis of higher elements.

No the primary reason we assume the Sun is full of Hyrdrogen and Helium is that its spectrum shows a lot of both of them. We also assume Hydrogen is the most abundant element in the Universe because even excluding the stars there are still massive clouds of the stuff both in our Galaxy and inbetween galaxies.

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oh, but didn't you guys know? all they're doing is "counting photons"--they might be missing some of the "different kinds." they might have even lost count--then where would we be?

look, Michael, until you can explain to anyone what "different kinds" of photons exist, perhaps you'd better not tell us how we know what we know, huh?

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Also you're setting up the BB Theory as a strawman. It's a common logical fallacy to misrepresent your opponent's argument so you can bash it down easily.

Short point, the BB is more than an assumption. It's a complex and involved theory worked out with math.

Look up "THEORY" in a scientific sense and you'll see that it is so far from an assumption it's silly to call the BB anything less than a solid scientific theory.

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I was watching the program 'Parallel Universes' and they had wonderful graphics showing the ripples of the branes and how that was responsible for the clumping.

OT I was wondering if the topological defect known as domain walls and textures--2D and 3D versions of Cosmic superstrings--might be pieces of 'naked (exposed) brane'. I also wonder if there may be a different imprint beyond the more usual warping of space-time by gravity--a different imprint obviating the need for missing mass--that might actually show its influence away from mass--by deep space probes deviating (over more than a solar system width tho').

Also--could exposed branes allow for some of the energy mass of a nearby budding universe to be shunted across--coming out of the exposed brane--and allowing the steady state folks some hope for at least some continued influx of matter--albeit in a smaller scale?

It just bums me out how everything is just going to be a void--with our galaxy being left alone.

If time pre-existed the Big Bang (as suggested by that Horizon program), could we learn the physics of branes by observing domain walls if we are so lucky as to see one?

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. 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. 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?

Keep in mind that we are still using the "count the photons" method of counting atoms. That is a dubious way to come up with percentages. 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. If the method is inaccurate in gleaning percentages it may still be damaging to the notion that iron was created after the BB.

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. 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? What evidence suggest s that iron did not predate the events of 0,0,0,0?

I'm not making up any strawmen here. I am simply questioning the ASSUMPTION that all matter formed from the events of 0,0,0,0. I specifically have come to doubt the notion that iron did not predate this event. I see no evidence this is true.

Wait a moment. I will grant you that there is 'math' to suggest that all the galaxies originated from an AREA of space that we can ROUGHLY identify. I do not know of any math that insists that it had to have been a "bang" (all matter created in the event) rather than a slam (matter predated the event). Do you?

Actually, that is one THEORY I have studied for quite some time and it is another theory I have come to questions, just as I question the THEORY that the sun is mostly made of hydrogen.

The belief that the universe is predominantly made of hydrogen springs from two basic ideas. The first idea is that all matter we have today was created in the events of the BB. The second pillar that this hydrogen idea is based on is the notion that by counting photons we can accurately predict solar composition. I see no evidence that either of these assumptions is true.

It is very hard for me to believe we are "alone" at all. In fact I suspect as we build better satellites, we'll find that what we call our physical universe (matter left after events at 0,0,0,0) is but one of many such events. The first law of thermodynamics insists that the energy to create this universe has existed eternally. The only question that remains is did matter predate the events of 0,0,0,0?

Agree, spectra from many stars show are full of hydrogen and helium. Seem logical conclusion.

There is only one KIND of photon, and many WAVELENGTHS and frequencies involved.

The bottom line here is that the current method to determine solar composition is based on the idea that you can count the number of photons from each element and use that number to determine how many atoms are present. That is not a scientifically sound method IMO since there is no method to account for ARRANGMENTS of the atoms and/or heat distribution.

The other pillar of the gas model is the BELIEF that all matter was created in the BB. Those two ASSUMPTIONS are the basis of the gas model theory. I think both ASSUMPTIONS are false.

The big bang is a POSSIBLE explanation. It's not the ONLY possible explanation. That's what I'm trying to suggest here. Even though we can plot trajectories of galaxies backwards in time, we cannot be sure that matter itself was created in this event. We ASSUME this. We BELIEVE this is the case. We do not KNOW this is the case.

What we SEE are photons. These photons are collected and measured. Someone had the idea that the amount of photons collected could help us determine overall composition. While I trust that it helps us to know while elements are present for certain, that method does not tell us what is NOT visible, or not emitting photons.

Even if stars are the only way to synthesize higher elements, how do we know that this process didn't occure TRILLIONS of years before the events of 0,0,0,0?

When you say "It shows a lot of both of them", what you really mean is that we see a lot of it. That really doesn't tell us what is there, only what is SHINING during the time of our measurements of the photons we collect. Spitzer is opening up the universe to all new spectrums of energy and it finds iron and silicon as far back in time as it can see, just like Hubble.

Again, there are two basic premises that unpin the gas model. The first premise is that the BB produced all matter, and the second one being that counting photon emissions will give us an accurate representation of solar composition. I see no way to justify either assumption based on current technology.

Ah but how is Spitzer finding these things? By looking at their photon emmissions. So if you want to prove your theory "counting photon emmissions" is OK but when anyone uses it to try to prove another one it isn't justified. Having ones cake and eating it.

Wrong, Hoyle did a large amount of work on on the steady state model and on thermonuclear fusion in stars. You don't need a big bang to have stars made of gas.

Personally I prefer looking at the composition of the Sun using methods of spectroscopy to examine what elements are present rather than examining meteors.

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Its better tae meddle wi the deil............

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.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.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'?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'?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'?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?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.I don't understand this - are you referring to cosmology? or stellar evolution and structure?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! 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, ...