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arXiv · hep-th/0612150

Variational Methods in AdS/CFT

T. Andrade·M. Banados·F. Rojas
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Abstract

We prove that the AdS/CFT calculation of 1-point functions can be drastically simplified by using variational arguments. We give a simple universal proof, valid for any theory that can be derived from a Lagrangian, that the large radius divergencies in 1-point functions can always be renormalized away (at least in the semiclassical approximation). The renormalized 1-point functions then follow by a simple variational problem involving only finite quantities. Several examples, a massive scalar, gravity, and renormalization flows, are discussed. Our results are general and can thus be used for dualities beyond AdS/CFT.

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T. Andrade, M. Banados, F. Rojas. 2009-05-16. Variational Methods in AdS/CFT. https://doi.org/10.1103/physrevd.75.065013

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