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arXiv 2003.051392020-03gr-qchep-th

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

Semin Xavier, Jose Mathew, S. Shankaranarayanan

备注：: v2: 15 pages, 1 figure, changed title, added an appendix, accepted in Classical and Quantum Gravity
DOI：: 10.1088/1361-6382/abbd0f

英文摘要：

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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