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Noncommuting charges can remove non-stationary quantum many-body dynamics
1Institute for Quantum Computing, University of Waterloo, Waterloo, ON, Canada. ssmajidy@gmail.com.
Noncommuting charges, or conserved quantities, can surprisingly enhance thermalization in quantum systems. Introducing new noncommuting charges disrupts dynamical symmetries, enabling systems to reach thermal equilibrium faster.
Area of Science:
- Quantum mechanics
- Statistical mechanics
- Condensed matter physics
Background:
- Many quantum systems reach thermal equilibrium via the Eigenstate Thermalization Hypothesis (ETH).
- Systems with dynamical symmetries violate ETH, exhibiting non-stationary dynamics and preventing thermalization.
- Noncommuting conserved quantities (charges) present a puzzle, with varied effects on thermalization.
Purpose of the Study:
- To investigate the role of noncommuting charges in quantum thermalization.
- To understand how dynamical symmetries impact thermalization.
- To determine if noncommuting charges can be leveraged to promote thermalization.
Main Methods:
- Analyzing the relationship between pairs of dynamical symmetries and charges.
- Introducing new, noncommuting charges into systems with existing dynamical symmetries.
- Examining the effects on system dynamics and thermalization across different models.
Main Results:
- Each pair of dynamical symmetries corresponds to a specific charge.
- Introducing noncommuting charges disrupts existing dynamical symmetries.
- Disruption of symmetries eliminates non-stationary dynamics, facilitating thermalization.
- This effect was observed in models like the Hubbard model and Heisenberg spin chains.
Conclusions:
- Noncommuting charges can be engineered to enhance quantum thermalization.
- Disrupting dynamical symmetries via noncommuting charges promotes equilibration.
- This work clarifies the complex role of noncommuting charges in quantum dynamics.
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