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arXiv · 2003.12771

Effective scalar-tensor description of regularized Lovelock gravity in four dimensions

Tsutomu Kobayashi
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Abstract

We reformulate the recently proposed regularized version of Lovelock gravity in four dimensions as a scalar-tensor theory. By promoting the warp factor of the internal space to a scalar degree of freedom by means of Kaluza-Klein reduction, we show that regularized Lovelock gravity can be described effectively by a certain subclass of the Horndeski theory. Cosmological aspects of this particular scalar-tensor theory are studied. It is found that the background with a scalar charge is generically allowed. The consequences of this scalar charge are briefly discussed.

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Tsutomu Kobayashi. 2020-03-28. Effective scalar-tensor description of regularized Lovelock gravity in four dimensions. https://doi.org/10.1088/1475-7516/2020/07/013

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