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arXiv · 2110.13882

Non-perturbative decoupling of massive fermions

Tobias Rindlisbacher·Kari Rummukainen·Ahmed Salami·Kimmo Tuominen
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Abstract

SU(2) gauge theory with Nf=24 massless fermions is non-interacting at long distances, i.e. it has an infrared fixed point at vanishing coupling. With massive fermions the fermions are expected to decouple at energy scales below the fermion mass, and the infrared behaviour is that of confining SU(2) pure gauge theory. We demonstrate this behaviour non-perturbatively with lattice Monte Carlo simulations by measuring the gradient flow running coupling.

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Tobias Rindlisbacher, Kari Rummukainen, Ahmed Salami, Kimmo Tuominen. 2022-09-02. Non-perturbative decoupling of massive fermions. https://doi.org/10.1103/physrevlett.129.131601

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