Article,
The AdS3 boundary energy momentum tensor, exact in the string length over the curvature radius
(Jun 22, 2010)
Abstract
We first clarify the relation between boundary perturbations of AdS3 in
general relativity, and exactly marginal worldsheet vertex operators in AdS3
string theory with Neveu-Schwarz Neveu-Schwarz flux. The latter correspond to
solutions of the higher derivative low-energy tree level effective action to
all orders in the string length over the curvature radius. We then calculate
the exact expression of the boundary energy momentum tensor including all these
higher derivative corrections in a purely bosonic string theory. The
bottom-line is a canonical shift in the normalization of the boundary
energy-momentum tensor corresponding to a shift in the curvature radius over
the string length squared by the dual Coxeter number of the SL(2,R) subalgebra
of the space-time Virasoro algebra. That allows us to derive the value of the
Brown-Henneaux central charge including all tree level higher derivative
corrections in bosonic string theory, in a scheme dictated by the worldsheet
conformal field theory.
