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arXiv · 2211.14335

Boundaries in Free Higher Derivative Conformal Field Theories

Adam Chalabi·Christopher P. Herzog·Krishnendu Ray·Brandon Robinson·Jacopo Sisti·Andreas Stergiou
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Abstract

We consider free higher derivative theories of scalars and Dirac fermions in the presence of a boundary in general dimension. We establish a method for finding consistent conformal boundary conditions in these theories by removing certain boundary primaries from the spectrum. A rich set of renormalization group flows between various conformal boundary conditions is revealed, triggered by deformations quadratic in the boundary primaries. We compute the free energy of these theories on a hemisphere, and show that the boundary $a$-theorem is generally violated along boundary flows as a consequence of bulk non-unitarity. We further characterize the boundary theory by computing the two-point function of the displacement operator.

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Adam Chalabi, Christopher P. Herzog, Krishnendu Ray, Brandon Robinson, Jacopo Sisti, Andreas Stergiou. 2022-11-25. Boundaries in Free Higher Derivative Conformal Field Theories. https://doi.org/10.1007/jhep04(2023)098

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