Latent Symmetry Induced Degeneracies.
M Röntgen1, M Pyzh1, C V Morfonios1
1Zentrum für optische Quantentechnologien, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
Physical Review Letters
|May 21, 2021
Summary
This study reveals latent symmetries in physical systems, explaining energy spectrum degeneracies. These symmetries, linked to effective Hamiltonians, offer new insights into accidental degeneracies and quantum system properties.
Area of Science:
- Quantum mechanics
- Spectroscopy
- Mathematical physics
Background:
- Energy spectrum degeneracies are typically attributed to accidental properties or Hamiltonian symmetries.
- Understanding the origin of these degeneracies is crucial for characterizing physical systems.
Purpose of the Study:
- To develop a novel approach for explaining energy spectrum degeneracies.
- To connect degeneracies to symmetries of an isospectral effective Hamiltonian derived via subsystem partitioning.
- To provide an intuitive interpretation of these latent symmetries.
Main Methods:
- Derivation of an isospectral effective Hamiltonian through subsystem partitioning.
- Analysis of local symmetries in powers of the Hamiltonian matrix.
- Application to degeneracies induced by rotation symmetry in real Hamiltonians.
Main Results:
- Degeneracies can be explained by tracing them back to latent symmetries of an effective Hamiltonian.
- Latent symmetries correspond to local symmetries in powers of the Hamiltonian matrix.
- Rotational symmetries in real Hamiltonians are linked to a non-Abelian latent symmetry group.
- Controlled breaking of rotational symmetries while preserving fundamental latent symmetry is demonstrated.
Conclusions:
- The developed approach provides a new framework for understanding energy degeneracies.
- Latent symmetries offer a deeper perspective on the origins of accidental degeneracies.
- This work opens avenues for investigating accidental degeneracies through the lens of latent symmetries.
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