Taste breaking in the minimally doubled Karsten-Wilczek action and its tree-level improvement
Abstract
Minimally doubled fermion actions offer a discretization for two-flavor Quantum Chromodynamics without rooting, but retaining a U(1) chiral symmetry at the same time. The price to pay is a breaking of the hypercubic symmetry, which requires the inclusion and tuning of new counterterms. Similar to staggered quarks, these actions suffer from taste breaking. We perform a mixed action numerical study with the Karsten-Wilczek formulation of minimally doubled fermions on 4stout staggered configurations, generated with physical quark masses, covering a broad range of lattice spacings. We consider a tree-level spatial Naik improvement to mitigate discretization errors. We carry out a non-perturbative tuning of the KW action with and without improvement, and investigate the taste breaking and the approach to the continuum limit.
Keywords
Cite
@article{arxiv.2502.07354,
title = {Taste breaking in the minimally doubled Karsten-Wilczek action and its tree-level improvement},
author = {S. Borsányi and S. Capitani and Z. Fodor and D. Godzieba and P. Parotto and R. A. Vig and C. H. Wong},
journal= {arXiv preprint arXiv:2502.07354},
year = {2025}
}
Comments
14 pages, 12 figures