# Microcanonical functional integral for the gravitational field.

@article{Brown1993MicrocanonicalFI, title={Microcanonical functional integral for the gravitational field.}, author={Brown and York}, journal={Physical review. D, Particles and fields}, year={1993}, volume={47 4}, pages={ 1420-1431 } }

The gravitational field in a spatially finite region is described as a microcanonical system. The density of states [nu] is expressed formally as a functional integral over Lorentzian metrics and is a functional of the geometrical boundary data that are fixed in the corresponding action. These boundary data are the thermodynamical extensive variables, including the energy and angular momentum of the system. When the boundary data are chosen such that the system is described semiclassically by… Expand

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