Linear and Second-order Geometry Perturbations on Spacetimes with Torsion. (arXiv:1901.06400v2 [gr-qc] UPDATED)

In order to study gravitational waves in any realistic astrophysical scenario, one must consider geometry perturbations up to second order. Here, we present a general technique for studying linear and quadratic perturbations on a spacetime with torsion. Besides the standard metric mode, a "torsionon" perturbation mode appears. This torsional mode will be able to propagate only in a certain kind of theories. 查看全文>>