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arXiv · 1807.08896

Towards nonsingular rotating compact object in ghost-free infinite derivative gravity

Luca Buoninfante·Alan S. Cornell·Gerhard Harmsen·Alexey S. Koshelev·Gaetano Lambiase·João Marto·Anupam Mazumdar
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Abstract

The vacuum solution of Einstein's theory of general relativity provides a rotating metric with a ring singularity, which is covered by the inner and outer horizons, and an ergo region. In this paper, we will discuss how ghost-free, quadratic curvature, Infinite Derivative Gravity (IDG) may resolve the ring singularity. In IDG the non-locality of the gravitational interaction can smear out the delta-Dirac source distribution by making the metric potential finite everywhere including at $r=0$. We show that the same feature also holds for a rotating metric. We can resolve the ring singularity such that no horizons are formed in the linear regime by smearing out a delta-source distribution on a ring. We will also show that the Kerr-metric does not solve the full non-linear equations of motion of ghost-free quadratic curvature IDG.

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Luca Buoninfante, Alan S. Cornell, Gerhard Harmsen, Alexey S. Koshelev, Gaetano Lambiase, João Marto, Anupam Mazumdar. 2018-11-27. Towards nonsingular rotating compact object in ghost-free infinite derivative gravity. https://doi.org/10.1103/physrevd.98.084041

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