We have computed the number of polarization modes of gravitational waves propagating in the Minkowski background in f(R) gravity. This is three of two from transverse-traceless tensor modes and one from a massive trace mode, which confirms the results found in the literature. There is no massless breathing mode and the massive trace mode corresponds to the Ricci scalar. A newly defined metric tensor in f(R) gravity satisfies the transverse-traceless (TT) condition as well as the TT wave equation.
@article{arxiv.1608.01764,
title = {Propagating degrees of freedom in f(R) gravity},
author = {Yun Soo Myung},
journal= {arXiv preprint arXiv:1608.01764},
year = {2016}
}
Comments
1+10 pages, no figure, published version in Adv. High Energy Phys