New Solutions for Non-Abelian Cosmic Strings.

Area of Science:

• High-energy physics
• Cosmology
• Theoretical physics

Background:

• Non-Abelian gauge theories exhibit complex phenomena like cosmic strings.
• Symmetry breaking in these theories leads to topological defects such as monopoles and strings.
• The SU(2) gauge theory with two adjoint Higgs fields is a key model for studying these phenomena.

Purpose of the Study:

• To investigate classical vortex solutions in a specific non-Abelian gauge theory.
• To analyze the properties and classifications of monopoles and string solutions.
• To explore the implications of emergent symmetries and their impact on topological defects.

Main Methods:

• Analysis of classical vortex solutions in an SU(2) gauge theory with two adjoint Higgs fields.
• Investigating symmetry breaking patterns and their relation to topological defects.
• Classifying monopoles and string solutions based on gauge-invariant quantities and charges.

Main Results:

• Identified 't Hooft-Polyakov monopoles trapped on cosmic strings, termed beads, with two charges and two degenerate string solutions.
• Discovered emergent discrete symmetries when Higgs field masses are degenerate, leading to additional string solutions and four types of "semipoles".
• Found that at special Higgs self-coupling values, continuous symmetry breaking yields supercurrents on strings, and semipoles/supercurrents are generic on Grand Unified Theory strings.

Conclusions:

• The study reveals novel topological defects, semipoles and supercurrents, in non-Abelian gauge theories.
• These findings have significant implications for understanding cosmic strings and Grand Unified Theories.
• The research highlights the importance of emergent symmetries in shaping the properties of fundamental physical phenomena.