http://arxiv.org/abs/1709.01671
We revisit gauge invariant cosmological perturbations in UV-modified, z = 3 Horava gravity with one scalar matter field, which has been proposed as a renormalizable gravity theory without the ghost problem in four dimensions. We confirm that there is no extra graviton modes and general relativity is recovered in IR, which achieves the consistency of the model. From the UV-modification terms which break the detailed balance condition in UV, we obtain scale-invariant power spectrums for non-inflationary backgrounds, like the power-law expansions, without knowing the details of early expansion history of Universe. This could provide a new framework for the Big Bang cosmology.
M. Park
Fri, 8 Sep 17
2/65
Comments: 5 pages, Prepared for Proceeding of International Joint Conference of ICGAC-XIII and IK15 (July 3-7, 2017, Seoul, Republic of Korea)