Gravitational Radiation in Hořava Gravity

May, 2011
30 pages
Published in:
  • Phys.Rev.D 84 (2011) 064004
e-Print:

Citations per year

2011201520192023202502468
Abstract: (arXiv)
We study the radiation of gravitational waves by self-gravitating binary systems in the low-energy limit of Horava gravity. We find that the predictions for the energy-loss formula of General Relativity are modified already for Newtonian sources: the quadrupole contribution is altered, in part due to the different speed of propagation of the tensor modes; furthermore, there is a monopole contribution stemming from an extra scalar degree of freedom. A dipole contribution only appears at higher post-Newtonian order. We use these findings to constrain the low-energy action of Horava gravity by comparing them with the radiation damping observed for binary pulsars. Even if this comparison is not completely appropriate - since compact objects cannot be described within the post-Newtonian approximation - it represents an order of magnitude estimate. In the limit where the post-Newtonian metric coincides with that of General Relativity, our energy-loss formula provides the strongest constraints for Horava gravity at low-energies.
  • 04.50.Kd
  • 04.60.Bc
  • 04.30.Db
  • pulsar: binary
  • gravitation: Horava-Lifshitz
  • gravitational radiation: multipole
  • energy loss
  • current: conservation law
  • energy: flux