The $g$-theorem from Strong Subadditivity

Jonathan Harper; Hiroki Kanda; Tadashi Takayanagi; Kenya Tasuki

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arXiv · 2403.19934

The $g$-theorem from Strong Subadditivity

Jonathan Harper·Hiroki Kanda·Tadashi Takayanagi·Kenya Tasuki

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Abstract

We show that strong subadditivity provides a simple derivation of the $g$-theorem for the boundary renormalization group flow in two-dimensional conformal field theories. We work out its holographic interpretation and also give a derivation of the $g$-theorem for the case of an interface in two-dimensional conformal field theories. We also geometrically confirm strong subadditivity for holographic duals of conformal field theories on manifolds with boundaries.

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Jonathan Harper, Hiroki Kanda, Tadashi Takayanagi, Kenya Tasuki. 2024-03-29. The $g$-theorem from Strong Subadditivity. https://arxiv.org/abs/2403.19934

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