Gravitational Waves: A Test for Modified Gravity

Lixin Xu

Published 2014-10-26Version 1

In a modified gravity theory, the propagation equation of gravitational waves will be in a non standard way. Therefore, it provides a crucial test on deviation of general relativity. In this paper, we propose a parameterized modification to the propagation of gravitational waves and study its effects on the tensor modes of cosmic microwave polarization B modes and its degeneracy to the tensor mode power spectrum index $n_t$ and its running $\alpha_t$. At last, we reported the current status on the detection to deviation of general relativity through the currently available data sets. Our results showed no significant deviation was probed.