Holographic Entanglement Entropy, Field Redefinition Invariance and Higher Derivative Gravity Theories

Understand

It is established that physical observables in local quantum field theories should be invariant under invertible field redefinitions.

• It is then expected that this statement should be true for the entanglement entropy and moreover that, via the gauge/gravity correspondence, the recipe for computing entanglement entropy holographically should also be invariant under local field redefinitions in the gravity side.
• We use this fact to fix the recipe for computing holographic entanglement entropy (HEE) for $f(R,R_{\mu\nu})$ theories which could be mapped to Einstein gravity.
• An outcome of our prescription is that the surfaces that minimize the corresponding HEE functional for $f(R,R_{\mu\nu})$ theories always have vanishing trace of extrinsic curvature and that the HEE may be evaluated using the Wald entropy functional.