# The 39th International Symposium on Lattice Field Theory (Lattice 2022)

Aug 8 – 13, 2022
Hörsaalzentrum Poppelsdorf
Europe/Berlin timezone

## Intra-taste eigenvalue splittings of staggered, KW and BC fermions in 2D

Aug 9, 2022, 7:00 PM
1h
Poster Presentation Theoretical Developments and Applications beyond Particle Physics

### Speaker

Stephan Durr (University of Wuppertal and Julich Supercomputing Centre)

### Description

Staggered fermions, Karsten-Wilczek (KW) fermions and Borici-Creutz (BC) fermions all retain a remnant chiral symmetry. The price to be payed is that they are doubled, and the resulting taste symmetry is broken by cut-off effects. We measure the size of the taste symmetry violation by determining the low-lying eigenvalues of these fermion operators in the two-dimensional Schwinger model which admits, like QCD, a global topological charge of a given gauge configuration. A first result is that it matters whether the pertinent eigenmode is a would-be zero-mode or a non-topological mode. The intra-pair splittings of the fermion formulations mentioned are found to depend sensitively on the gauge coupling $\beta$. Still, it turns out that it is surprisingly difficult to verify standard Symanzik scaling for these taste-breaking effects.

### Primary author

Stephan Durr (University of Wuppertal and Julich Supercomputing Centre)

### Co-author

Maximilian Ammer (Wuppertal University)