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arXiv · hep-th/0212072

Schwinger-Keldysh Propagators from AdS/CFT Correspondence

C. P. Herzog·D. T. Son
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Abstract

We demonstrate how to compute real-time Green's functions for a class of finite temperature field theories from their AdS gravity duals. In particular, we reproduce the two-by-two Schwinger-Keldysh matrix propagator from a gravity calculation. Our methods should work also for computing higher point Lorentzian signature correlators. We elucidate the boundary condition subtleties which hampered previous efforts to build a Lorentzian-signature AdS/CFT correspondence. For two-point correlators, our construction is automatically equivalent to the previously formulated prescription for the retarded propagator.

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C. P. Herzog, D. T. Son. 2003-04-02. Schwinger-Keldysh Propagators from AdS/CFT Correspondence. https://doi.org/10.1088/1126-6708%2F2003%2F03%2F046

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