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arXiv · 1710.05990

Space-time slicing in Horndeski theories and its implications for non-singular bouncing solutions

Anna Ijjas
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Abstract

In this paper, we show how the proper choice of gauge is critical in analyzing the stability of non-singular cosmological bounce solutions based on Horndeski theories. We show that it is possible to construct non-singular cosmological bounce solutions with classically stable behavior for all modes with wavelengths above the Planck scale where: (a) the solution involves a stage of null-energy condition violation during which gravity is described by a modification of Einstein's general relativity; and (b) the solution reduces to Einstein gravity both before and after the null-energy condition violating stage. Similar considerations apply to galilean genesis scenarios.

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Anna Ijjas. 2017-10-16. Space-time slicing in Horndeski theories and its implications for non-singular bouncing solutions. https://doi.org/10.1088/1475-7516%2F2018%2F02%2F007

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