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marcus
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#139
Feb14-12, 09:34 AM
Astronomy
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Quote Quote by atyy View Post
It's standard. All the different quantum gravity approaches have gravitons at low energy. The differences are in whether at high energy they still exist in a similar form or whether something completely different like strings are needed.
I agree. A perturbative approach is useful (even essential) for calculation at low energy. Loop, for instance "has gravitons" when one is explicitly studying low density, nearly flat, geometries. Low energy=low curvature, so that kind of approximation works.

I don't take issue with that. It's not a good way to picture reality when you are thinking about big bang cosmology. I take issue with someone calling the flat picture the real "territory" and the GR picture a mere "map".