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arXiv · 1506.06713

Cusp singularities in f(R) gravity: pros and cons

Pisin Chen·Dong-han Yeom
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Abstract

We investigate cusp singularities in f(R) gravity, especially for Starobinsky and Hu-Sawicki dark energy models. We illustrate that, by using double-null numerical simulations, a cusp singularity can be triggered by gravitational collapses. This singularity can be cured by adding a quadratic term, but this causes a Ricci scalar bump that can be observed by an observer outside the event horizon. Comparing with cosmological parameters, it seems that it would be difficult to see super-Planckian effects by astrophysical experiments. On the other hand, at once there exists a cusp singularity, it can be a mechanism to realize a horizon scale curvature singularity that can be interpreted by a firewall.

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Pisin Chen, Dong-han Yeom. 2015-10-13. Cusp singularities in f(R) gravity: pros and cons. https://doi.org/10.1088/1475-7516%2F2015%2F10%2F022

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