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arXiv · 1909.11676

Bounds on Triangle Anomalies in (3+1)d

Ying-Hsuan Lin·David Meltzer·Shu-Heng Shao·Andreas Stergiou
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Abstract

How many charged degrees of freedom are necessary to accommodate a certain amount of 't Hooft anomaly? Using the conformal bootstrap for the four-point function of flavor current multiplets, we show that in all (3+1)d superconformal field theories the 't Hooft anomaly of a continuous flavor symmetry is bounded from above by the 3/2 power of the current two-point function coefficient, which can be thought of as a measure for the amount of charged degrees of freedom. We check our bounds against free fields and SQCD in the conformal window.

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Ying-Hsuan Lin, David Meltzer, Shu-Heng Shao, Andreas Stergiou. 2020-06-09. Bounds on Triangle Anomalies in (3+1)d. https://doi.org/10.1103/physrevd.101.125007

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