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arXiv · 1803.03955

On singularity-resolution in mimetic gravity

Suddhasattwa Brahma·Alexey Golovnev·Dong-han Yeom
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Abstract

Recently, it was shown that modified mimetic gravity, with a $f(\square\phi)$ term, results in a singularity-free model of gravity, for both cosmological and black hole spacetimes [1, 2]. In this work, we analyze this model further and show that, since the function $f$ was tuned to vanish rapidly for small values of the argument, the non-singular bounce relies heavily on a subtle branch changing mechanism for the multi-valued function $f$. Furthermore, this mechanism has interesting implications for the proposed link between this model and loop quantum cosmology.

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Suddhasattwa Brahma, Alexey Golovnev, Dong-han Yeom. 2018-03-11. On singularity-resolution in mimetic gravity. https://doi.org/10.1016/j.physletb.2018.05.039

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