Defect structures in Lorentz and CPT violating scenarios
Abstract
We investigate models described by real scalar fields, searching for defect structures in the presence of interactions which explicitly violate Lorentz and CPT symmetries. We first deal with a single field, and we investigate a class of models which supports traveling waves that violate Lorentz invariance. This scenario is then generalized to the case of two (or more) real scalar fields. In the case of two fields, in particular, we introduce another class of models, which supports topological structures that attain a Bogomol'nyi bound, although violating both Lorentz and CPT symmetries. An example is considered, for which we construct the Bogomol'nyi bound and find some explicit solutions. We show that violation of both Lorentz and CPT symmetries induces the appearance of an asymmetry between defects and antidefects, including the presence of linearly stable solutions with negative energy density in their outer side.
 Authors:
 Departamento de Fisica, Universidade Federal da Paraiba, 58051970 Joao Pessoa, Paraiba (Brazil)
 (Portugal)
 Publication Date:
 OSTI Identifier:
 20782686
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.73.065015; (c) 2006 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; ASYMMETRY; CPT THEOREM; DEFECTS; ENERGY DENSITY; LORENTZ INVARIANCE; MATHEMATICAL SOLUTIONS; SCALAR FIELDS; SYMMETRY; SYMMETRY BREAKING; TOPOLOGY; TRAVELLING WAVES
Citation Formats
Barreto, M.N., Bazeia, D., Menezes, R., and Centro de Fisica e Departamento de Fisica, Universidade do Porto, Porto. Defect structures in Lorentz and CPT violating scenarios. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.065015.
Barreto, M.N., Bazeia, D., Menezes, R., & Centro de Fisica e Departamento de Fisica, Universidade do Porto, Porto. Defect structures in Lorentz and CPT violating scenarios. United States. doi:10.1103/PHYSREVD.73.065015.
Barreto, M.N., Bazeia, D., Menezes, R., and Centro de Fisica e Departamento de Fisica, Universidade do Porto, Porto. Wed .
"Defect structures in Lorentz and CPT violating scenarios". United States.
doi:10.1103/PHYSREVD.73.065015.
@article{osti_20782686,
title = {Defect structures in Lorentz and CPT violating scenarios},
author = {Barreto, M.N. and Bazeia, D. and Menezes, R. and Centro de Fisica e Departamento de Fisica, Universidade do Porto, Porto},
abstractNote = {We investigate models described by real scalar fields, searching for defect structures in the presence of interactions which explicitly violate Lorentz and CPT symmetries. We first deal with a single field, and we investigate a class of models which supports traveling waves that violate Lorentz invariance. This scenario is then generalized to the case of two (or more) real scalar fields. In the case of two fields, in particular, we introduce another class of models, which supports topological structures that attain a Bogomol'nyi bound, although violating both Lorentz and CPT symmetries. An example is considered, for which we construct the Bogomol'nyi bound and find some explicit solutions. We show that violation of both Lorentz and CPT symmetries induces the appearance of an asymmetry between defects and antidefects, including the presence of linearly stable solutions with negative energy density in their outer side.},
doi = {10.1103/PHYSREVD.73.065015},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}

We calculate, by the method of dimensional regularization and derivative expansion, the oneloop effective action for a Dirac fermion with a Lorentzviolating and CPTodd kinetic term in the background of a gauge field. We show that this term induces a ChernSimons modification to Maxwell theory. Some related issues are also discussed. [copyright] [ital 1999] [ital The American Physical Society]

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