Nonminimal gradient flows in QCD-like theories


The Yang-Mills gradient flow for QCD-like theories is generalized by including a fermionic matter term in the gauge field flow equation. We combine this with two different flow equations for the fermionic degrees of freedom. The solutions for the different gradient flow setups are used in the perturbative computations of the vacuum expectation value of the Yang-Mills Lagrangian density and the field renormalization factor of the evolved fermions up to next-to-leading order in the coupling. We find a one-parameter family of flow systems for which there exists a renormalization scheme in which the evolved fermion anomalous dimension vanishes to all orders in perturbation theory. The fermion number dependence of different flows is studied and applications to lattice studies are anticipated.

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ArXiv ePrint: 2011.05316

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Boers, M. Nonminimal gradient flows in QCD-like theories. J. High Energ. Phys. 2021, 204 (2021).

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  • Lattice QCD
  • Perturbative QCD
  • Renormalization Group