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Non-existence of a dilaton gravity action for the exact string black hole

D. Grumiller·D. Vassilevich
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Abstract

We prove that no local diffeomorphism invariant two-dimensional theory of the metric and the dilaton without higher derivatives can describe the exact string black hole solution found a decade ago by Dijkgraaf, Verlinde and Verlinde. One of the key points in this proof is the concept of dilaton-shift invariance. We present and solve (classically) all dilaton-shift invariant theories of two-dimensional dilaton gravity. Two such models, resembling the exact string black hole and generalizing the CGHS model, are discussed explicitly.

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D. Grumiller, D. Vassilevich. 2002-11-07. Non-existence of a dilaton gravity action for the exact string black hole. https://doi.org/10.1088/1126-6708%2F2002%2F11%2F018

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