EDIT: Looks like Robert already answered this. If I had known I wouldn't have posted. Thanks Robert. Good links!
Anyway this is what I wrote earlier, attempting to respond.
yousless said:
Can anyone tell where I can find the mathematical proof of the Big Bang theory and by whom, I'm interest in the calculation only.
If you have a scientific paper available with you please send it to me(yousifhot@hotmail.com) I really need it.
Thanks a lot,
In the mathematical sciences like cosmology the way a theory is confirmed is by comparing a model with empirical data.
I am not sure what you mean by Big Bang theory. that is a name that caught on in the popular media and I think it often is used to refer to the standard cosmology model, which is some math equations (Friedmann equations)
What you do with the Friedmann equations model is you plug in some values of the parameters and see how it fits the data. The test is how well you can make a single choice of like 3 main numbers and then have it predict all the data in sight. All kinds of data----galaxy counts and redshifts, supernovas, the temperature map of the microwave background---all sorts of relatively old and relatively new stuff!
The fit is amazing. so the 3 or so main numbers (the parameters) can be determined with remarkable precision and reliability.
This is a big change since 1998. Before 1998 there were various competing guesses as to how to model the universe and what parameters to use. Now the data is a lot better. Better instruments helped.
anyway the way the model is confirmed is by fitting to a huge body of observations.
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once you have the Friedmann model you can just look at it and it is obvious that, since it is always expanding for all our past history, if you follow it back in time you get to a condition of very high density and temperature
I wouldn't call that a theory. It is more a little piece. It is just an automatic feature of the model that fits all the data over all time in the best way we know, so far. It's how the model that fits begins telling the whole story.
someday when we get a better model (if we do) maybe it will have a slightly different beginning. To me, for what it's worth, the beginning is not the most important feature. What impresses me is how well it covers the whole story.
Actually I think the details right around the beginning may change as the model is quantized, so people won't describe right at the start with the same words, probably won't say bang, may say bounce or something else. But that is just a little detail. We will still have a beautiful fit to the whole of the history that we can see.
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I'm still sort of wondering what you mean by "the Big Bang theory" and what it is you would like a proof of. would you like to describe a bit more
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