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arXiv · 1709.08169

Entanglement entropy of singular surfaces under relevant deformations in holography

Mostafa Ghasemi·Shahrokh Parvizi
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Abstract

In the vacuum state of a CFT, the entanglement entropy of singular surfaces contains a logarithmic universal term which is only due to the singularity of the entangling surface. We consider the relevant perturbation of a three dimensional CFT for singular entangling surface. We observe that in addition to the universal term due to the entangling surface, there is a new logarithmic term which corresponds to a relevant perturbation of the conformal field theory with a coefficient depending on the scaling dimension of the relevant operator. We also find a new power law divergence in the holographic entanglement entropy. In addition, we study the effect of a relevant perturbation in the Gauss-Bonnet gravity for a singular entangling surface. Again a logarithmic term shows up. This new term is proportional to both the dimension of the relevant operator and the Gauss-Bonnet coupling. We also introduce the renormalized entanglement entropy for a kink region which in the UV limit reduces to a universal positive finite term.

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Mostafa Ghasemi, Shahrokh Parvizi. 2018-01-16. Entanglement entropy of singular surfaces under relevant deformations in holography. https://doi.org/10.1007/jhep02(2018)009

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