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arXiv · 1011.0623

Dynamics of Diffeomorphism Degrees of Freedom at a Horizon

Hyeyoun Chung
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Abstract

We define a set of boundary conditions that ensure the presence of a null hypersurface with the essential characteristics of a horizon, using the formalism of weakly isolated horizons as a guide. We then determine the diffeomorphisms that preserve these boundary conditions, and derive a dynamical action for these diffeomorphisms in a neighbourhood of the horizon. The action is similar to that of Liouville theory, and the equation of motion of the gravitational degrees of freedom approaches that of a free two-dimensional conformal field theory in the near-horizon region.

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Hyeyoun Chung. 2011-03-19. Dynamics of Diffeomorphism Degrees of Freedom at a Horizon. https://doi.org/10.1103/physrevd.83.084017

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