Linearized gravity / Linearized Einstein Field Equations / GEM

[JustinLevy]

Are the phrases "Linearized gravity", "Linearized Einstein Field Equations", "GEM (gravitoelectrodynamics)", all referring to mathematically equivalent approximations of Einstein's full non-linear field equations?

If not, could someone tell me what order (in some rough sense) these would be listed in order of "approximating away" more terms from the full equations?

And is there any experimental data yet that let's us verify "strong field" GR as opposed to just weak field tests (ie. distinguish between the linear approximations and the full non-linear field equations)?

 

[Chris Hillman]

Suggest some arxiv eprints

I deprecate using the term "linearized gravity", since gtr is not the only theory of gravitation, not even the only classical relativistic field theory of gravitation, not even the only currently viable classical relativistic field theory of gravitation. However, the "linearized EFE" plays the same role in "linearized gtr" that the EFE plays in gtr proper.

There are several things one might mean by "gravitomagnetism"; see for example this review paper, which discusses two theories, one using the Bel decomposition of the Riemann tensor which always valid (in particular, works for strong-field gtr), and the other the GEM formalism which is indeed basically a reformulation of weak-field gtr (vacuum fields).

As for observational tests of strong-field gtr, see for example http://arxiv.org/abs/gr-qc/0402007