Dynamical breakdown of Abelian gauge chiral symmetry by strong Yukawa interactions
Abstract
We consider a model with anomalyfree Abelian gauge axialvector symmetry, which is intended to mimic the standard electroweak gauge chiral SU(2){sub L}xU(1){sub 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 selfenergies, which are ultravioletfinite and chirally noninvariant. (2) Solutions of the underlying SchwingerDyson 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 'wouldbe' NambuGoldstone boson is a composite of both the fermion and scalar fields, and it gives rise to the mass of the axialvector gauge boson. (4) Spontaneous breakdown of the gauge symmetry further manifests by mass splitting of the complex scalar and by new symmetrybreaking vertices, generated at one loop. In particular, we work out in detail the cubic vertex of the Abelian gauge boson.
 Authors:
 Department of Theoretical Physics, Nuclear Physics Institute, Rez (Prague) (Czech Republic)
 (Czech Republic)
 Publication Date:
 OSTI Identifier:
 21020105
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevD.75.056003; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRAL SYMMETRY; CHIRALITY; FERMIONS; GAUGE INVARIANCE; GOLDSTONE BOSONS; MATHEMATICAL SOLUTIONS; REST MASS; SCALAR FIELDS; SCHWINGER FUNCTIONAL EQUATIONS; SELFENERGY; STANDARD MODEL; STRONG INTERACTIONS; SU2 GROUPS; SYMMETRY BREAKING; U1 GROUPS; ULTRAVIOLET RADIATION
Citation Formats
Benes, Petr, Brauner, Tomas, Faculty of Mathematics and Physics, Charles University, Prague, and Hosek, Jiri. Dynamical breakdown of Abelian gauge chiral symmetry by strong Yukawa interactions. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.056003.
Benes, Petr, Brauner, Tomas, Faculty of Mathematics and Physics, Charles University, Prague, & Hosek, Jiri. Dynamical breakdown of Abelian gauge chiral symmetry by strong Yukawa interactions. United States. doi:10.1103/PHYSREVD.75.056003.
Benes, Petr, Brauner, Tomas, Faculty of Mathematics and Physics, Charles University, Prague, and Hosek, Jiri. Thu .
"Dynamical breakdown of Abelian gauge chiral symmetry by strong Yukawa interactions". United States.
doi:10.1103/PHYSREVD.75.056003.
@article{osti_21020105,
title = {Dynamical breakdown of Abelian gauge chiral symmetry by strong Yukawa interactions},
author = {Benes, Petr and Brauner, Tomas and Faculty of Mathematics and Physics, Charles University, Prague and Hosek, Jiri},
abstractNote = {We consider a model with anomalyfree Abelian gauge axialvector symmetry, which is intended to mimic the standard electroweak gauge chiral SU(2){sub L}xU(1){sub 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 selfenergies, which are ultravioletfinite and chirally noninvariant. (2) Solutions of the underlying SchwingerDyson 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 'wouldbe' NambuGoldstone boson is a composite of both the fermion and scalar fields, and it gives rise to the mass of the axialvector gauge boson. (4) Spontaneous breakdown of the gauge symmetry further manifests by mass splitting of the complex scalar and by new symmetrybreaking vertices, generated at one loop. In particular, we work out in detail the cubic vertex of the Abelian gauge boson.},
doi = {10.1103/PHYSREVD.75.056003},
journal = {Physical Review. D, Particles Fields},
number = 5,
volume = 75,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}

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