8 research outputs found
Back reaction, covariant anomaly and effective action
In the presence of back reaction, we first produce the one-loop corrections
for the event horizon and Hawking temperature of the Reissner-Nordstr\"om black
hole. Then, based on the covariant anomaly cancelation method and the effective
action technique, the modified expressions for the fluxes of gauge current and
energy momentum tensor, due to the effect of back reaction, are obtained. The
results are consistent with the Hawking fluxes of a (1+1)-dimensional blackbody
at the temperature with quantum corrections, thus confirming the robustness of
the covariant anomaly cancelation method and the effective action technique for
black holes with back reaction.Comment: 17 page
Two Virasoro symmetries in stringy warped AdS
41 pages, 1 figureInternational audienceWe study three-dimensional consistent truncations of type IIB supergravity which admit warped AdS solutions. These theories contain subsectors that have no bulk dynamics. We show that the symplectic form for these theories, when restricted to the non-dynamical subsectors, equals the symplectic form for pure Einstein gravity in AdS. Consequently, for each consistent choice of boundary conditions in AdS, we can define a consistent phase space in warped AdS with identical conserved charges. This way, we easily obtain a Virasoro X Virasoro asymptotic symmetry algebra in warped AdS; two different types of Virasoro X Kac-Moody symmetries are also consistent alternatives. Next, we study the phase space of these theories when propagating modes are included. We show that, as long as one can define a conserved symplectic form without introducing instabilities, the Virasoro X Virasoro asymptotic symmetries can be extended to the entire (linearized) phase space. This implies that, at least at semi-classical level, consistent theories of gravity in warped AdS are described by a two-dimensional conformal field theory, as long as stability is not an issue