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arXiv · 0805.1902

Setting the boundary free in AdS/CFT

Geoffrey Compère·Don Marolf
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Abstract

We describe a new class of boundary conditions for AdS_{d+1} under which the boundary metric becomes a dynamical field. The key technical point is to show that contributions from boundary counter-terms in the bulk gravitational action render such fluctuations normalizable. In the context of AdS/CFT, the analogue of Neumann boundary conditions for AdS promotes the CFT metric to a dynamical field but adds no explicit gravitational dynamics; the gravitational dynamics is just that induced by the conformal fields. Other AdS boundary conditions couple the CFT to a gravity theory of choice. We use this correspondence to briefly explore the coupled CFT + gravity theories and, in particular, for d=3 we show that coupling topologically massive gravity to a large N CFT preserves the perturbative stability of the theory with negative (3-dimensional) Newton's constant.

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Geoffrey Compère, Don Marolf. 2008-06-04. Setting the boundary free in AdS/CFT. https://doi.org/10.1088/0264-9381%2F25%2F19%2F195014

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