25 July 2007 to 1 August 2007
Karlsruhe University
Europe/Zurich timezone

Dynamical breakdown of Abelian gauge chiral symmetry by strong Yukawa interactions

31 Jul 2007, 14:20
20m
Small Auditorium B (Karlsruhe University)

Small Auditorium B

Karlsruhe University

Wolfgang-Gaede-Str. 1 76131 Karlsruhe Germany
Parallel Talk Alternatives Alternatives 6

Speaker

Mr Petr Benes (Department of Theoretical Physics, Nuclear Physics Institute, Rez near Prague, Czech Republic)

Description

We consider a model with anomaly-free Abelian gauge axial-vector symmetry, which is intended to mimic the standard electroweak gauge chiral SU(2)_L x U(1)_Y theory. Within this model we demonstrate: (1) Strong Yukawa interactions between massless fermion fields and a massive scalar field carrying the axial charge generate dynamically the fermion and boson proper self- energies, which are ultraviolet-finite and chirally noninvariant. (2) Solutions of the underlying Schwinger-Dyson equations found numerically exhibit a huge amplification of the fermion mass ratios as a response to mild changes of the ratios of the Yukawa couplings. (3) The `would-be' Nambu-Goldstone boson is a composite of both the fermion and scalar fields, and it gives rise to the mass of the axial-vector gauge boson. (4) Spontaneous breakdown of the gauge symmetry further manifests by mass splitting of the complex scalar and by new symmetry-breaking vertices, generated at one loop. In particular, we work out in detail the cubic vertex of the Abelian gauge boson. Based on Phys.Rev. D75 (2007) 056003 (arXiv:hep-ph/0605147).

Authors

Dr Jiri Hosek (Department of Theoretical Physics, Nuclear Physics Institute, Rez near Prague, Czech Republic) Mr Petr Benes (Department of Theoretical Physics, Nuclear Physics Institute, Rez near Prague, Czech Republic) Dr Tomas Brauner (Department of Theoretical Physics, Nuclear Physics Institute, Rez near Prague, Czech Republic)

Presentation materials