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Noninvertible Symmetry-Resolved Affleck-Ludwig-Cardy Formula and Entanglement Entropy from the Boundary Tube Algebra
Yichul Choi1,2,3, Brandon C Rayhaun2, Yunqin Zheng2
1School of Natural Sciences, <a href="https://ror.org/00f809463">Institute for Advanced Study</a>, Princeton University, Princeton, New Jersey 08540, USA.
We refined the Affleck-Ludwig-Cardy formula for 1+1D conformal field theories with noninvertible symmetries. This allows calculation of symmetry-resolved entanglement entropy, revealing Hopf algebra symmetry in the double Ising model.
Area of Science:
- Theoretical Physics
- Quantum Field Theory
- Condensed Matter Physics
Background:
- The Affleck-Ludwig-Cardy formula describes state densities in conformal field theories.
- Noninvertible global symmetries introduce new complexities in quantum systems.
- Entanglement entropy quantifies quantum correlations in subsystems.
Purpose of the Study:
- To derive a refined Affleck-Ludwig-Cardy formula for 1+1D conformal field theories with noninvertible symmetries.
- To compute universal contributions to noninvertible symmetry-resolved entanglement entropy.
- To investigate the symmetry properties of the double Ising model's entanglement Hamiltonian.
Main Methods:
- Derivation of a refined Affleck-Ludwig-Cardy formula.
- Analysis of noninvertible symmetry-resolved entanglement entropy.
- Application to the critical double Ising model with specific boundary conditions.
- Utilizing recent advancements in symmetry topological field theories.
Main Results:
- A refined formula for asymptotic density of high energy states under noninvertible symmetries.
- Determination of universal leading and subleading contributions to symmetry-resolved entanglement entropy.
- Identification of a Kac-Paljutkin H8 Hopf algebra symmetry in the double Ising model's ground state entanglement Hamiltonian.
- Calculation of corresponding symmetry-resolved entanglement entropies for the double Ising model.
Conclusions:
- The refined formula provides a powerful tool for studying quantum systems with noninvertible symmetries.
- The findings offer new insights into the structure of entanglement and symmetry in critical phenomena.
- The concrete example of the double Ising model demonstrates the practical application of the derived methods.
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