Originally Posted by SkinWalker
I'm not referring to the "proof" that you can get in mathematics: 12 into 24 = 2, which you can prove by multplying 12 by 2 which equals 24.
I rather understand your meanings, I just don't like the term 'proven' in relation to science. I'm certainly no Popperian, but I do prefer 'not falsified' and 'strongly coroborated' as terms.
Proven just strikes me as too concrete a term.
Originally Posted by IG-64
In order to date something billions of years old, you have to assume the universe is billions of years old in the first place.
No, in order to date something to that age you simply need to know the rate of decay in certain radioactive elements. Uranium-235, for example, decays into Lead-207. Uranium-235 has a half-life of 704 million years, so any rock that contains an even distribution of those two elements is likely to be approximately 704 million years old. There are several different elements used in this form of dating, and as Skinwalker has said, there are other observational methods (Seafloor spreading, etc.).
Edit - Just saw this article
on CNN. It seemed pertinant.