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arXiv · 1710.10956

Testing a non-perturbative mechanism for elementary fermion mass generation: lattice setup

Stefano Capitani·Giulia Maria de Divitiis·Petros Dimopoulos·Roberto Frezzotti·Marco Garofalo·Bastian Knippschild·Bartosz Kostrzewa·Ferenc Pittler·Giancarlo Rossi·Carsten Urbach
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Abstract

In this contribution we lay down a lattice setup that allows for the non-perturbative study of a field theoretical model where a SU(2) fermion doublet, subjected to non-Abelian gauge interactions, is also coupled to a complex scalar field doublet via a Yukawa and an "irrelevant" Wilson-like term. Using naive fermions in quenched approximation and based on the renormalized Ward identities induced by purely fermionic chiral transformations, lattice observables are discussed that enable: a) in the Wigner phase, the determinations of the critical Yukawa coupling value where the purely fermionic chiral transformation become a symmetry up to lattice artifacts; b) in the Nambu-Goldstone phase of the resulting critical theory, a stringent test of the actual generation of a fermion mass term of non-perturbative origin. A soft twisted fermion mass term is introduced to circumvent the problem of exceptional configurations, and observables are then calculated in the limit of vanishing twisted mass.

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Stefano Capitani, Giulia Maria de Divitiis, Petros Dimopoulos, Roberto Frezzotti, Marco Garofalo, Bastian Knippschild, Bartosz Kostrzewa, Ferenc Pittler, Giancarlo Rossi, Carsten Urbach. 2017-10-27. Testing a non-perturbative mechanism for elementary fermion mass generation: lattice setup. https://doi.org/10.1051/epjconf%2F201817508009

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