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Sean Clayden
2008-Mar-06, 08:57 PM
OK, as a novice, treat me with some respect, but where did all the matter within the universe come from. All the elements that we know of are spread throughout the universe, and there is a lot of it in various forms, some we have not discovered yet, but where did it all come from ?

WalrusLike
2008-Mar-06, 10:01 PM
I am not an expert, only only an interested observer... But as I understand it...

Einstein tells us that E=MC2. Which is to say that mass can convert to energy... and energy can condense to mass. Current thinking is that nearly 14 billion years ago there was a massive outpouring of energy from a single 'point'.... the big bang. Those early conditions... physics seems to be reasonably confident right up to tiny fractions of a second after that 'big bang'... but before that, or how or why it happened are in still in the realm of the unknown.

I am not checking my number facts so I may be out by a tad... but they are roughly correct... a few hundred thousand years later the universe had cooled enough for light photons to be able to survive long enough to burst forth... the 'stuff' of the universe became suddenly transparent and the dark ages of the universe was over. Now that initial light has travelled out in all directions (changing colour as it went to the point where now we 'see' it as radio waves....) the snow on your tv screen when it is not on a channel is partly those waves finally reaching us. They come from all directions and are known as the Cosmic Microwave Background.... the left over 'noise' from the big bang. Much can be worked out from looking at maps of the distribution of that light.

Now initially it was all pure energy at unimaginable 'temperature'. Gradually it cooled until it could condense into mass. Just like water can gradually cool and become a lump of ice... a phase change (of sorts). Some of that mass (at that point nearly(??) all Hydrogen atoms) coalesced under the influence of gravity to form the first generation of stars. They were big and short lived (only millions(??) of years) and they exploded at the end of their life spectacularly... and in the nuclear fusion furnace at their heart, in that moment of explosion, they fused and formed heavier atoms... Then the whole star formation thing happens again, but this time round with more stable, more varied composition, stars that lived for a lot longer... and then again it happens.... (I think from memory that our Sun is one of those 'third time round' stars.) Nowadays we have a mix of the second and later generations.... plus a few odd things like neutron stars and black holes... basically stars that have a slightly different life cycle.

So the gold, iron, oxygen, chlorine, uranium... every atom that we see, eat, breath or touch.... and even the all the atoms of our own bodies... was initially formed out of pure energy and then fused in the heart of a star. We are truly made of starstuff. (I think Carl Sagan said that...)

Trocisp
2008-Mar-06, 10:05 PM
to expand on WalrusLike's post; A star has a generation, much like a family. 1st generation stars were Hydrogen and Helium, with trace (trace trace) amounts of heavier elements up to boron (?? I think it is boron ??).

All heavier elements were fused together inside of a star (iron, calcium, gold, etc).

The further into the generational list a star is, the more and more heavy elements it accumulates (on average). Of course there will be some generation -1 stars with more heavy elements than generation 0 stars, but that's rare (the exception, rather than the rule).

Also, I believe the generational chart starts with 4 (or 3?) and counts down to 1 (or 0?), rather than starting at 1 and counting up... I could be incorrect though, because I have no idea why I think this, where normally I have some idea if i read it or saw it.

Our star (if my thinking is correct, which it could very well be erroneous) is a generation 1 (or 0?).

Sean Clayden
2008-Mar-06, 10:06 PM
But formed from what.....Singularity ? What did singularity consist of......

Trocisp
2008-Mar-06, 10:10 PM
The generally accepted theory of this singularity is a unification of the fundamental forces of nature.

Gravity, Strong nuclear force, weak nuclear force and electromagnetism.

This had all of the energy in the universe, (all the matter was at that time in energy form following E=mc2).

Asking for any causation before a few tenths of a second after the big bang is impossible, at this point, as very few theories work this far back into the universe, and those that do are riddled with holes/inaccuracies that need to be ironed out before they're accepted.

WalrusLike
2008-Mar-06, 10:23 PM
But formed from what.....Singularity ? What did singularity consist of......

Ah.... I see I misunderstood what you were asking... sorry bout that.

The question you ask can not, unfortunately, be answered now (or perhaps ever) by science. If it can't be tested and disproven then, by definition, it is not 'science'.... since that 'falseifieability' (is that even a word?? :) ) is part of the commonly accepted definition of science.

So you are asking a philosophical, or perhaps religious, question...

I have very little knowledge in those areas (and precious little all round, if truth is told :) ) so I wont presume to answer.

I can say that science tells us that 'time' is tied inextricably to 'space' and that at the initial 'point' (call it the big bang... or singularity if you like...) there was no space or time.... so there was no 'before the big bang'.

There is a lot of current speculation that the event happened as a result of fluctuations in the quantum vacuum..... but it gets so far from stuff that I, as a layman, can understand that it seems pointless to me to consider it until the dust settles.

Sean Clayden
2008-Mar-07, 08:35 AM
Thank you.....

Sitnalta
2008-Mar-08, 04:42 AM
The question you ask can not, unfortunately, be answered now (or perhaps ever) by science. If it can't be tested and disproven then, by definition, it is not 'science'.... since that 'falseifieability' (is that even a word?? :) ) is part of the commonly accepted definition of science.

So you are asking a philosophical, or perhaps religious, question...

If science doesn't have an answer, then philosophical or religious discussion won't have one either. Well, that's not entirely accurate.. they'll have an answer, it just won't be the correct answer.

I think it's knowable. It'll just take some more investigation, some dynamite theories, and a hell of a lot of smart people.