skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Intercommutation of Semilocal Strings and Skyrmions

Abstract

We study the intercommuting of semilocal strings and Skyrmions for a wide range of internal parameters, velocities, and intersection angles by numerically evolving the equations of motion. We find that the collisions of strings and strings, strings and Skyrmions, and Skyrmions and Skyrmions all lead to intercommuting for a wide range of parameters. Even the collisions of unstable Skyrmions and strings lead to intercommuting, demonstrating that the phenomenon of intercommuting is very robust, extending to dissimilar field configurations that are not stationary solutions. Even more remarkably, at least for the semilocal U(2) formulation considered here, all intercommutations trigger a reversion to Nielsen-Olesen strings.

Authors:
; ; ;  [1];  [2];  [2]
  1. Department of Astronomy and Astrophysics, IGPG, CGWP, Penn State University, University Park, Pennsylvania 16802 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20861632
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevLett.98.041602; (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; EQUATIONS OF MOTION; MATHEMATICAL SOLUTIONS; SKYRME POTENTIAL; SOLITONS; STRING MODELS; U-2 GROUPS

Citation Formats

Laguna, Pablo, Natchu, Vishnu, Matzner, Richard A., Vachaspati, Tanmay, Center for Relativity, Department of Physics, University of Texas at Austin, Austin, Texas 78712, and CERCA, Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7079. Intercommutation of Semilocal Strings and Skyrmions. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.041602.
Laguna, Pablo, Natchu, Vishnu, Matzner, Richard A., Vachaspati, Tanmay, Center for Relativity, Department of Physics, University of Texas at Austin, Austin, Texas 78712, & CERCA, Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7079. Intercommutation of Semilocal Strings and Skyrmions. United States. doi:10.1103/PHYSREVLETT.98.041602.
Laguna, Pablo, Natchu, Vishnu, Matzner, Richard A., Vachaspati, Tanmay, Center for Relativity, Department of Physics, University of Texas at Austin, Austin, Texas 78712, and CERCA, Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7079. Fri . "Intercommutation of Semilocal Strings and Skyrmions". United States. doi:10.1103/PHYSREVLETT.98.041602.
@article{osti_20861632,
title = {Intercommutation of Semilocal Strings and Skyrmions},
author = {Laguna, Pablo and Natchu, Vishnu and Matzner, Richard A. and Vachaspati, Tanmay and Center for Relativity, Department of Physics, University of Texas at Austin, Austin, Texas 78712 and CERCA, Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7079},
abstractNote = {We study the intercommuting of semilocal strings and Skyrmions for a wide range of internal parameters, velocities, and intersection angles by numerically evolving the equations of motion. We find that the collisions of strings and strings, strings and Skyrmions, and Skyrmions and Skyrmions all lead to intercommuting for a wide range of parameters. Even the collisions of unstable Skyrmions and strings lead to intercommuting, demonstrating that the phenomenon of intercommuting is very robust, extending to dissimilar field configurations that are not stationary solutions. Even more remarkably, at least for the semilocal U(2) formulation considered here, all intercommutations trigger a reversion to Nielsen-Olesen strings.},
doi = {10.1103/PHYSREVLETT.98.041602},
journal = {Physical Review Letters},
number = 4,
volume = 98,
place = {United States},
year = {Fri Jan 26 00:00:00 EST 2007},
month = {Fri Jan 26 00:00:00 EST 2007}
}
  • Dark strings have recently been suggested to exist in new models of dark matter that explain the excessive electronic production in the Galaxy. We study the interaction of these dark strings with semilocal strings which are solutions of the bosonic sector of the standard model in the limitsin{sup 2}{theta}{sub w}=1, where {theta}{sub w} is the Weinberg angle. While embedded Abelian-Higgs strings exist for generic values of the coupling constants, we show that semilocal solutions with nonvanishing condensate inside the string core exist only above a critical value of the Higgs to gauge boson mass ratio when interacting with dark strings.more » Above this critical value, which is greater than unity, the energy per unit length of the semilocal-dark string solutions is always smaller than that of the embedded Abelian-Higgs-dark string solutions and we show that Abelian-Higgs-dark strings become unstable above this critical value. Different from the noninteracting case, we would thus expect semilocal strings to be stable for values of the Higgs to gauge boson mass ratio larger than unity. Moreover, the one-parameter family of solutions present in the noninteracting case ceases to exist when semilocal strings interact with dark strings.« less
  • It has recently been shown that a certain model field theory (which gives the Abelian Higgs model a global SU(2) symmetry by duplicating the scalar sector) possesses static finite-energy vortex solutions despite having a simply connected vacuum manifold. It is demonstrated here that they are stable or unstable according to whether {ital m}{sub {ital s}} is less than or greater than {ital m}{sub {ital v}} (where {ital m}{sub {ital s}} and {ital m}{sub {ital v}} are the masses of the Higgs and vector particles, respectively). At the boundary, {ital m}{sub {ital s}}={ital m}{sub {ital v}}, there is a two-parameter familymore » of solutions all saturating a Bogomol'nyi bound. The relationship of the vortices to CP{sup {ital n}} {sigma}-model lumps is pointed out.« less
  • We carry out three-dimensional numerical simulations to investigate the formation rate of semilocal strings. We find that the backreaction of the gauge fields on the scalar field evolution is substantial, and leads to a significant formation rate in the parameter regime where the semilocal strings are classically stable. The formation rate can be as large as one-third of that for cosmic strings, depending on the model parameters. {copyright} {ital 1999} {ital The American Physical Society}
  • We show that the presence of global symmetries in a Lagrangian can lead to U(1) flux-tube solutions even when the vacuum manifold is simply connected. We provide a model in which these flux tubes, called semilocal'' strings, occur and explicitly prove the existence of stable string solutions by Bogomol'nyi's method. The formation of semilocal strings in the early Universe and the evolution of the network is discussed. We also show that semilocal magnetic monopoles cannot exist.