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Published on: June 28, 2018
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Quantum spherical spins with local symmetry.
Pedro R S Gomes1, P F Bienzobaz1
1Department of Physics, Boston University, Boston, Massachusetts 02215, USA.
Summary
This study explores a quantum system of spherical spins, revealing spontaneous symmetry breaking that leads to phase transitions at various temperatures. It also investigates the dynamical generation of gauge fields.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Statistical mechanics
Background:
- Investigating quantum systems with continuous local symmetry is crucial for understanding complex phenomena.
- Spherical spin models offer a tractable framework for studying symmetry breaking and phase transitions.
Purpose of the Study:
- To construct and analyze a quantum system of spherical spins with continuous local symmetry.
- To explore spontaneous symmetry breaking and its implications for phase transitions.
- To investigate the dynamical generation of gauge fields and its relation to symmetry restoration.
Main Methods:
- Exact solution in the thermodynamic limit.
- Analysis of spontaneous symmetry breaking at finite and zero temperatures.
- Investigation of the equivalence with the CP(N-1) model in the N→∞ limit.
Main Results:
- The constructed quantum system exhibits spontaneous local symmetry breaking.
- Both classical and quantum phase transitions with nontrivial critical behavior are identified.
- Dynamical generation of gauge fields is shown to be a consequence of local symmetry restoration.
Conclusions:
- The model provides a soluble platform for studying symmetry breaking and phase transitions in quantum systems.
- The findings offer insights into the interplay between symmetry, gauge fields, and critical phenomena.
- The research connects spherical spin models to established theoretical frameworks like the CP(N-1) model.
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