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Old 12-May-2008, 04:13 PM
Tensor Tensor is offline
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Quote:
Originally Posted by tommac View Post
Well that was my question, how does one determine what metric to use?
By using the manifold you get when you solve the Einstein Field Equations. The metric tensor comes from the tangent spaces of the manifold. Mathematically, it drops out as a matrix, once you decide what coordinate system you want to use (remember, GR is coordinate free, it allows you to use any arbitrary set of coordinates). It was explained in the link in my original answer.
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