Gravitation-Wave Emission in Shift-Symmetric Horndeski Theories

Enrico Barausse and Kent Yagi

Phys. Rev. Lett. 115, 211105 – Published 20 November 2015

Abstract

Gravity theories beyond general relativity typically predict dipolar gravitational emission by compact-star binaries. This emission is sourced by “sensitivity” parameters depending on the stellar compactness. We introduce a general formalism to calculate these parameters, and show that in shift-symmetric Horndeski theories stellar sensitivities and dipolar radiation vanish, provided that the binary’s dynamics is perturbative (i.e., the post-Newtonian formalism is applicable) and cosmological-expansion effects can be neglected. This allows one to reproduce the binary-pulsar-observed orbital decay.

Received 15 September 2015

DOI:https://doi.org/10.1103/PhysRevLett.115.211105

Authors & Affiliations

Enrico Barausse¹ and Kent Yagi^2,3

¹Sorbonne Universités, UPMC Université Paris 6 and CNRS, UMR 7095, Institut d’Astrophysique de Paris, 98 bis boulevard Arago, 75014 Paris, France
²Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
³Department of Physics, Montana State University, Bozeman, Montana 59717, USA