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Effective Action and Thermodynamics of Radiating Shells in General Relativity

G. L. Alberghi·R. Casadio·G. Venturi
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Abstract

An effective action is obtained for the area and mass aspect of a thin shell of radiating self-gravitating matter. On following a mini-superspace approach, the geometry of the embedding space-time is not dynamical but fixed to be either Minkowski or Schwarzschild inside the shell and Vaidya in the external space filled with radiation. The Euler-Lagrange equations of motion are discussed and shown to entail the expected invariance of the effective Lagrangian under time-reparametrization. They are equivalent to the usual junction equations and suggest a macroscopic quasi-static thermodynamic description.

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G. L. Alberghi, R. Casadio, G. Venturi. 1999-09-06. Effective Action and Thermodynamics of Radiating Shells in General Relativity. https://doi.org/10.1103/physrevd.60.124018

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