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arXiv · 1509.02160

A Constraint on Defect and Boundary Renormalization Group Flows

Kristan Jensen·Andy O'Bannon
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Abstract

A conformal field theory (CFT) in dimension $d\geq 3$ coupled to a planar, two-dimensional, conformal defect is characterized in part by a "central charge" $b$ that multiplies the Euler density in the defect's Weyl anomaly. For defect renormalization group flows, under which the bulk remains critical, we use reflection positivity to show that $b$ must decrease or remain constant from ultraviolet to infrared. Our result applies also to a CFT in $d=3$ flat space with a planar boundary.

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Kristan Jensen, Andy O'Bannon. 2015-09-17. A Constraint on Defect and Boundary Renormalization Group Flows. https://doi.org/10.1103/physrevlett.116.091601

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