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Quantum Radiation from Black Holes

Daniel Hofmann
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Abstract

The expectation value of the energy-momentum tensor and the Hawking flux of a scalar field on a Schwarzschild spacetime is calculated using the zeta-function regularisation of the heat kernel. In particular, massless particles are considered in a spherically reduced dilaton model. The effective action is thereby obtained by the covariant perturbation theory and the boundary conditions are fixed by means of the energy-momentum conservation equation. In contrast to previous approaches the expectation values are calculated directly from the effective action which itself is derived in a straightforward manner.

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Daniel Hofmann. 2002-09-03. Quantum Radiation from Black Holes. https://arxiv.org/abs/gr-qc/0209007

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