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arXiv · 2003.05139

Infinitely degenerate exact Ricci-flat solutions in f(R) gravity

Semin Xavier·Jose Mathew·S. Shankaranarayanan
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Abstract

We obtain an infinite number of exact static, Ricci-flat spherically symmetric vacuum solutions for a class of f(R) theories of gravity. We analytically derive two exact vacuum black-hole solutions for the same class of f(R) theories. The two black-hole solutions have the event-horizon at the same point; however, their asymptotic features are different. Our results suggest that no-hair theorem may not hold for generic modified gravity theories. We discuss the implications of our work to distinguish modified gravity theories from general relativity in gravitational wave detections.

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Semin Xavier, Jose Mathew, S. Shankaranarayanan. 2020-03-11. Infinitely degenerate exact Ricci-flat solutions in f(R) gravity. https://doi.org/10.1088/1361-6382/abbd0f

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