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arXiv · 1109.1923

The AdS3 central charge in string theory

Jan Troost
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Abstract

We evaluate the vacuum expectation value of the central charge operator in string theory in an AdS3 vacuum. Our calculation provides a rare non-zero one-point function on a spherical worldsheet. The evaluation involves the regularization both of a worldsheet ultraviolet divergence (associated to the infinite volume of the conformal Killing group), and a space-time infrared divergence (corresponding to the infinite volume of space-time). The two divergences conspire to give a finite result, which is the classical general relativity value for the central charge, corrected in bosonic string theory by an infinite series of tree level higher derivative terms.

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Jan Troost. 2011-09-09. The AdS3 central charge in string theory. https://doi.org/10.1016/j.physletb.2011.10.007

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