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arXiv · 2110.14784

Palatini kinetic scalar-tensor theory: analytical and numerical solutions

D. V. Gal'tsov·D. S. Bushuev
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Abstract

We investigate static spherically symmetric solutions in the Palatini kinetically coupled scalar-tensor theory, which reduces to gravity minimally coupled to a scalar field in Einstein frame. Using the fact that the Jordan and Einstein frame are related by a reversible disformal transformation, which can be solved in closed form, we derive the general solution in the Jordan frame and show that it does not contain black holes. There is a wormhole branch and a naked singularity branch between which lies a non-singular asymptotically flat solution with kernel $M_{1,1}\times S^2$. This theory strongly violates the null energy condition.

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D. V. Gal'tsov, D. S. Bushuev. 2021-10-27. Palatini kinetic scalar-tensor theory: analytical and numerical solutions. https://arxiv.org/abs/2110.14784

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