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Weak cosmic censorship with self-interacting scalar and bound on charge to mass ratio

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 Added by Yongqiang Wang
 Publication date 2020
  fields Physics
and research's language is English




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We study the model of Einstein-Maxwell theory minimally coupling to a massive charged self-interacting scalar field, parameterized by the quartic and hexic coupling, labelled by $lambda$ and $beta$, respectively. In the absence of scalar field, there is a class of counterexamples to cosmic censorship. Moveover, we investigate the properties of full nonlinear solution with nonzero scalar field, and argue that, by assuming massive charged self-interacting scalar field with sufficiently large charge above one certain bound, these counterexamples can be removed. In particular, this bound on charge for self-interacting scalar field is no longer equal to the weak gravity bound for free scalar case. In the quartic case, the bounds are below free scalar case for $lambda<0$, while above free scalar case for $lambda>0$. Meanwhile, in the hexic case, the bounds are above free scalar case for both $beta>0$ and $beta<0$.

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