merrill@rex.DEC (12/04/84)
We do get information ABOUT a black hole but never FROM a black hole. (One can get information about a person of the opposite sex without "knowing" them. -- appologies to anyone who misconstrues the analogy -- and to spelling freaks!) Uh, JC, has anyone Proven that gravitational waves/field travel at the speed of light? RMM
gwyn@brl-tgr.ARPA (Doug Gwyn <gwyn>) (12/06/84)
> Uh, JC, has anyone Proven that gravitational waves/field travel at the > speed of light? The gravitational field does not "travel" at all. Disturbances in the field are another matter. The linearized gravity "waves" can be decomposed into three modes (T-T, T-L, and L-L). Two of these (I forget which) can be shown to move at the speed of light (assuming the General Theory of Relativity, of course). The story on the third is a bit confusing, partly due to the strong relation between the metric tensor and the contracted curvature tensor (in the extended theory).