On Holographic Defect Entropy

Understand

We study a number of (3+1)- and (2+1)-dimensional defect and boundary conformal field theories holographically dual to supergravity theories.

• In all cases the defects or boundaries are planar, and the defects are codimension-one.
• Using holography, we compute the entanglement entropy of a (hemi-)spherical region centered on the defect (boundary).
• We define defect and boundary entropies from the entanglement entropy by an appropriate background subtraction.