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→Thoughts on Field theory?: classical -> GR -> QM
:Looks like a solid start to me. I'm no physicist, but I'm always one for motivating examples at the beginning of an article. Maybe write down the gravitational field and resulting motion for some simple system? I think Newtonian gravitation is usually called a "classical field theory" or something along those lines, without requiring any sort of carrier particle. I'll jump in with my thoughts when I have a chance, but I'm drowned in work this week.
:Looks like a solid start to me. I'm no physicist, but I'm always one for motivating examples at the beginning of an article. Maybe write down the gravitational field and resulting motion for some simple system? I think Newtonian gravitation is usually called a "classical field theory" or something along those lines, without requiring any sort of carrier particle. I'll jump in with my thoughts when I have a chance, but I'm drowned in work this week.
:PS: I'm not sure about the claim that GR requires/predicts gravitons -- it's my understanding that gravitons come out of QFT, a framework in contrast with the GR understanding of gravity as resulting from curved spacetime. But my knowledge here is really just from pop physics books I read a few years back -- hopefully someone with a better understanding can clarify. --[[User:MarkGall|MarkGall]] 22:32, 1 November 2009 (EST)
:PS: I'm not sure about the claim that GR requires/predicts gravitons -- it's my understanding that gravitons come out of QFT, a framework in contrast with the GR understanding of gravity as resulting from curved spacetime. But my knowledge here is really just from pop physics books I read a few years back -- hopefully someone with a better understanding can clarify. --[[User:MarkGall|MarkGall]] 22:32, 1 November 2009 (EST)
::We should discuss the "classical" field theories first—Newtonian gravity and Faraday/Maxwell electrodynamics. They give a clear flavor of what a "field" might be. (Though Newton had never heard of fields; his gravity became a "gravitational field" centuries later.) Then we should mention that General Relativity is also a field theory of sorts, but it involves tensor fields that are far beyond the scope of CP. (Alas, GR is just too hairy for non-experts, and we can't do anything about it.) Only then should we go into quantum field theories. By the way, gravitons relate to quantum field theories, and were not in the original GR. I believe they arise from Yang-Mills gauge theories, which were invented in 1954, long after GR (1915). [[User:PatrickD|PatrickD]] 22:47, 1 November 2009 (EST)