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arXiv · hep-th/9302022

A Unitary S-matrix for 2D Black Hole Formation and Evaporation

Erik Verlinde·Herman Verlinde
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Abstract

We study the black hole information paradox in the context of a two-dimensional toy model given by dilaton gravity coupled to $N$ massless scalar fields. After making the model well-defined by imposing reflecting boundary conditions at a critical value of the dilaton field, we quantize the theory and derive the quantum quantum $S$-matrix for the case that $N$=$24$. This $S$-matrix is unitary by construction, and we further argue that in the semiclassical regime it describes the formation and subsequent Hawking evaporation of two-dimensional black holes. Finally, we note an interesting correspondence between the dilaton gravity $S$-matrix and that of the $c=1$ matrix model.

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Erik Verlinde, Herman Verlinde. 1993-02-07. A Unitary S-matrix for 2D Black Hole Formation and Evaporation. https://doi.org/10.1016/0550-3213(93)90160-q

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