Nonconservative Unimodular Gravity: Gravitational Waves

Colliding gravitational plane waves in dilaton gravity.

Collision of plane waves in dilaton gravity theories and low energy limit of string theory is considered. The formulation of the problem and some exact solutions are presented PACS: 04.20.Jb , 04.40.Nr , 04.30.Nk , 11.27.+d

Helicity-Rotation-Gravity Coupling for Gravitational Waves

The consequences of spin-rotation-gravity coupling are worked out for linear gravitational waves. The coupling of helicity of the wave with the rotation of a gravitational-wave antenna is investigated and the resulting modifications in the Doppler effect and aberration are pointed out for incident high-frequency gravitational radiation. Extending these results to the case of a gravitomagnetic f...

Troubles for Unimodular Gravity

We compute the contribution of various gravitational instantons to the path integral in the standard formulation of unimodular gravity, an alternative theory of gravity where the determinant of the metric is not dynamical. Following similar computations in General Relativity, we derive the entropy/area ratio for cosmological and black hole horizons, finding in general disagreement with General ...

Projected Constraints on Lorentz-Violating Gravity with Gravitational Waves

Gravitational waves are excellent tools to probe the foundations of General Relativity in the strongly dynamical and non-linear regime. One such foundation is Lorentz symmetry, which can be broken in the gravitational sector by the existence of a preferred time direction, and thus, a preferred frame at each spacetime point. This leads to a modification in the orbital decay rate of binary system...

Stochastic background of gravitational waves ”tuned” by f(R) gravity