Covariant formulation of non-equilibrium thermodynamics in General Relativity

  title={Covariant formulation of non-equilibrium thermodynamics in General Relativity},
  author={Llorenç Espinosa-Portal{\'e}s and Juan Garc{\'i}a-Bellido},
  journal={Physics of the Dark Universe},
We construct a generally-covariant formulation of non-equilibrium thermodynamics in General Relativity. We find covariant entropic forces arising from gradients of the entropy density, and a corresponding non-conservation of the energy momentum tensor in terms of these forces. We also provide a Hamiltonian formulation of General Relativity in the context of non-equilibrium phenomena and write the Raychaudhuri equations for a congruence of geodesics. We find that a fluid satisfying the strong… 
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