Notes on Derivation of 'Generalized Gravitational Entropy'

Understand

An alternative derivation of generalized gravitational entropy associated to co-dimension 2 'entangling' hypersurfaces is given.

• The approach is similar to the Jacobson-Myers 'Hamiltonian' method and it does not require computations on manifolds with conical singularities.
• It is demonstrated that the entangling surfaces should be extrema of the entropy functional.
• When our approach is applied to Lovelock theories of gravity the generalized entropy formula coincides with results derived by other methods.