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Intercommutation of semilocal strings and Skyrmions
Pablo Laguna1, Vishnu Natchu, Richard A Matzner
1Department of Astronomy and Astrophysics, IGPG, CGWP, Penn State University, University Park, Pennsylvania 16802, USA.
Physical Review Letters
|March 16, 2007
Summary
Intercommuting of semilocal strings and Skyrmions is robust across various parameters. Collisions, even with unstable configurations, result in intercommuting and reversion to Nielsen-Olesen strings.
Area of Science:
- High-energy physics
- Theoretical physics
- Cosmology
Background:
- Semilocal strings and Skyrmions are topological solitons with distinct properties.
- Understanding their interactions is crucial for models of the early universe and particle physics.
Purpose of the Study:
- To investigate the phenomenon of intercommuting between semilocal strings and Skyrmions.
- To determine the robustness and outcomes of these interactions under varied conditions.
Main Methods:
- Numerical evolution of equations of motion.
- Simulation of collisions involving strings and Skyrmions with diverse parameters, velocities, and angles.
Main Results:
- Intercommuting was observed for all collision types: string-string, string-Skyrmion, and Skyrmion-Skyrmion.
- The phenomenon proved robust, occurring even with unstable field configurations.
- All intercommutations resulted in a reversion to Nielsen-Olesen strings in the U(2) formulation.
Conclusions:
- Intercommuting is a highly robust feature of semilocal strings and Skyrmions.
- These interactions are not limited to stable, stationary solutions.
- The U(2) semilocal model consistently shows a reversion to Nielsen-Olesen strings post-intercommutation.
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