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arXiv · 2004.01404

Novel cosmological and black hole solutions in Einstein and higher-derivative gravity in two dimensions

Shin'ichi Nojiri·Sergei D. Odintsov
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Abstract

We consider cosmological and black hole solutions in the Einstein and higher-derivative gravity in two dimensions where the theory is formulated first in $D$ dimensions. In the limit that $D$ tends to $2$ with simultaneous singular rescaling of the scalar curvature coupling constant as $1/(D-2)$, we get the novel Einstein and higher-derivative gravity. Due to non-trivial contribution of scalar curvature which is topological invariant in exactly two dimensions to gravitational equations in the two-dimensional limit one gets novel cosmological and black hole solutions.In particular, the de Sitter and radiation-dominated universe and the Schwarzschild-de Sitter and Schwarzschild-anti-de Sitter black hole solutions are obtained and their properties are discussed.

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Shin'ichi Nojiri, Sergei D. Odintsov. 2020-04-03. Novel cosmological and black hole solutions in Einstein and higher-derivative gravity in two dimensions. https://doi.org/10.1209/0295-5075/130/10004

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