The black hole horizon as a quantum surface

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 to the self dual projection of the fundamental surface elements Wμν.