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arXiv · 1511.07449

$\mathcal{N}=2$ central charge bounds from $2d$ chiral algebras

Madalena Lemos·Pedro Liendo
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Abstract

We study protected correlation functions in $\mathcal{N} = 2$ SCFT whose description is captured by a two-dimensional chiral algebra. Our analysis implies a new analytic bound for the $c$-anomaly as a function of the flavor central charge $k$, valid for any theory with a flavor symmetry $G$. Combining our result with older bounds in the literature puts strong constraints on the parameter space of $\mathcal{N}=2$ theories. In particular, it singles out a special set of models whose value of $c$ is uniquely fixed once $k$ is given. This set includes the canonical rank one $\mathcal{N}=2$ SCFTs given by Kodaira's classification.

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Madalena Lemos, Pedro Liendo. 2015-11-23. $\mathcal{N}=2$ central charge bounds from $2d$ chiral algebras. https://doi.org/10.1007/jhep04(2016)004

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