MG15 - Talk detail

Back to previous page

 Participant

Institution

Session

Accepted

Yes

Order

Time

Talk

Title

Abstract

Propagating shock-waves can be discussed in terms of junction conditions between space-time regions separated by a hypersurface. Recent observations of gravitational waves and their electromagnetic counterparts established that the former also propagate with the speed of light. Hence energetic gravitational waves could be perceived as shock-waves on null hypersurfaces. The most generic scalar-tensor theories with at most second order dynamics, the Horndeski-theories were severely constrained. We derive generic junction conditions for the subclass of allowed Horndeski-theories with linear kinetic term dependence, exploring a formalism based on a transverse vector, rather than normal, which can be applied to any type of hypersurfaces, including null. In the particular case of a non-null hypersurface we obtain a generalised Lanczos equation, with the jump of the extrinsic curvature induced by both the distributional energy-momentum tensor of the wavefront of the shock-wave, and by the jump in the transverse derivative of the scalar. For null hypersurfaces we derive constraints on the surface density, current and pressure of a distributional light-like shock-wave.

Pdf file

Back to previous page