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arXiv · 2501.10862

Symmetries and Anomalies of Hamiltonian Staggered Fermions

Simon Catterall·Arnab Pradhan·Abhishek Samlodia
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Abstract

We review the shift (translation) and time reversal symmetries of Hamiltonian staggered fermions and their connection to continuum symmetries concentrating in particular on the case of massless fermions and (3+1) dimensions. We construct operators using the staggered fields that implement these symmetries on finite lattices. We show that shifts composed of an odd multiple of the elementary shift anti-commute with time reversal and are related to continuum axial transformations. We argue that the presence of these non-trivial commutation relations implies the existence of lattice 't Hooft anomalies. From the shifts we also construct a set of conserved, quantized charges that generate continuous symmetries of the lattice theory. In general these do not commute with the vector charge signaling further 't Hooft anomalies.

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Simon Catterall, Arnab Pradhan, Abhishek Samlodia. 2025-10-24. Symmetries and Anomalies of Hamiltonian Staggered Fermions. https://arxiv.org/abs/2501.10862

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