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arXiv · 2306.05944

Conformal anomalies in 6d 4-derivative theories: a heat-kernel analysis

Lorenzo Casarin
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Abstract

We compute the conformal anomalies for some higher-derivative (non-unitary) 6d Weyl invariant theories using the heat-kernel expansion in the background-field method. To this aim we obtain the general expression for the Seeley-DeWitt coefficient $b_6$ for four-derivative differential operators with background curved geometry and gauge fields, which was known only in flat space so far. We consider four-derivative scalars and abelian vectors as well as three-derivative fermions, confirming the result of the literature obtained via indirect methods. We generalise the vector case by including the curvature coupling $FF \mathrm{Weyl}$.

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Lorenzo Casarin. 2023-06-09. Conformal anomalies in 6d 4-derivative theories: a heat-kernel analysis. https://doi.org/10.1103/physrevd.108.025014

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