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Boulware state in exactly solvable models of 2D dilaton gravity

O. B. Zaslavskii
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Abstract

We discuss self-consistent geometries and behavior of dilaton in exactly solvable models of 2D dilaton gravity, with quantum fields in the Boulware state. If the coupling $H(ϕ)$ between curvature and dilaton $ϕ$ is non-monotonic, backreaction can remove the classical singularity. As a result, an everywhere regular star-like configuration may appear, in which case the Boulware state, contrary to expectations, smooths out the system. For monotonic $H(ϕ)$ exact solutions confirm the features found before with the help of numerical methods: the appearance of the bouncing point and the presence of isotropic singularity at the classically forbidden branch of the dilaton.

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O. B. Zaslavskii. 2006-10-02. Boulware state in exactly solvable models of 2D dilaton gravity. https://doi.org/10.1142/s0217732306021529

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