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Thermal divergences on the event horizons of two-dimensional black holes

Daniel J. Loranz·William A. Hiscock·Paul R. Anderson
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Abstract

The expectation value of the stress-energy tensor $\langleT_{μν}\rangle$ of a free conformally invariant scalar field is computed in a general static two-dimensional black hole spacetime when the field is in either a zero temperature vacuum state or a thermal state at a nonzero temperature. It is found that for every static two-dimensional black hole the stress-energy diverges strongly on the event horizon unless the field is in a state at the natural black hole temperature which is defined by the surface gravity of the event horizon. This implies that both extreme and nonextreme two-dimensional black holes can only be in equilibrium with radiation at the natural black hole temperature.

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Daniel J. Loranz, William A. Hiscock, Paul R. Anderson. 1995-04-25. Thermal divergences on the event horizons of two-dimensional black holes. https://doi.org/10.1103/physrevd.52.4554

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