Flavor symmetries and unitarity bounds in $\mathcal{N}=2$ SCFTs

Abstract

In this letter I analyze the constraints imposed by unitarity on the flavor central charges of four-dimensional $\mathcal{N}=2$ SCFTs with general reductive global symmetry groups. I derive several general and far-reaching consequences of unitarity by computing the norms of flavor singlet Higgs branch operators appearing in the squares of "moment map" operators via the associated vertex operator algebra, and imposing the requirement that they be non-negative.

5 pages, 2 column format. v2: factors of two corrected to provide consistent conventions for Segal-Sugawara vectors. streamlined argument for equation 10

References in corpus (3)

• Chiral Algebras for Trinion Theories
• N=2 S-duality Revisited
• Chiral algebras of class $\mathcal{S}$ and Moore-Tachikawa symplectic varieties

Cited by in corpus (21)

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• More on holographic correlators: Twisted and dimensionally reduced structures
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• A geometric free field realisation for the genus-two class $\mathcal{S}$ theory of type ${\mathfrak{a}}_1$
• The Hitchhiker's Guide to 4d $\mathcal{N}=2$ Superconformal Field Theories
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• The Chiral Algebra of Genus Two Class $\mathcal{S}$ Theory
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• 4d/2d $\to$ 3d/1d: A song of protected operator algebras
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• Bridging 4D QFTs and 2D VOAs via 3D high-temperature EFTs
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• Twisted chiral algebras of class $\mathcal{S}$ and mixed Feigin-Frenkel gluing