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Vacuum polarization in two-dimensional static spacetimes and dimensional reduction

Roberto Balbinot·Alessandro Fabbri·Piero Nicolini·Patrick J. Sutton
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Abstract

We obtain an analytic approximation for the effective action of a quantum scalar field in a general static two-dimensional spacetime. We apply this to the dilaton gravity model resulting from the spherical reduction of a massive, non-minimally coupled scalar field in the four-dimensional Schwarzschild geometry. Careful analysis near the event horizon shows the resulting two-dimensional system to be regular in the Hartle-Hawking state for general values of the field mass, coupling, and angular momentum, while at spatial infinity it reduces to a thermal gas at the black-hole temperature.

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Roberto Balbinot, Alessandro Fabbri, Piero Nicolini, Patrick J. Sutton. 2002-05-14. Vacuum polarization in two-dimensional static spacetimes and dimensional reduction. https://doi.org/10.1103/physrevd.66.024014

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