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arXiv · 1512.04953

Holographic entanglement entropy of surface defects

Simon A. Gentle·Michael Gutperle·Chrysostomos Marasinou
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Abstract

We calculate the holographic entanglement entropy in type IIB supergravity solutions that are dual to half-BPS disorder-type surface defects in ${\cal N}=4$ Super Yang-Mills theory. The entanglement entropy is calculated for a ball-shaped region bisected by a surface defect. Using the bubbling supergravity solutions we also compute the expectation value of the defect operator. Combining our result with the previously-calculated one-point function of the stress tensor in the presence of the defect, we adapt the calculation of Lewkowycz and Maldacena to obtain a second expression for the entanglement entropy. Our two expressions agree up to an additional term, whose possible origin and significance is discussed

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Simon A. Gentle, Michael Gutperle, Chrysostomos Marasinou. 2016-03-30. Holographic entanglement entropy of surface defects. https://doi.org/10.1007/jhep04(2016)067

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