The Black hole horizon as a quantum surface

  title={The Black hole horizon as a quantum surface},
  author={Gerard 't Hooft},
  journal={Physica Scripta},
  • G. Hooft
  • Published 1991
  • Physics
  • Physica Scripta
In previous work it was argued why it is practically inevitable to assume the existence of an S-matrix that describes particle absorption and production by a black hole, and the relationship between this S-matrix and string theory was derived. The physical interpretation of the corresponding mathematical expressions however is quite different from string theory. We have an algebra of operators now defined on a two-dimensional Euclidean "world sheet". The algebra simplifies if one restricts it… 
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