Global and nonlocal magic of quantum many-body scars
Abstract
Nonergodic features of chaotic quantum many-body systems are commonly characterized through local observables, fidelity, and entanglement entropy. Here, using global and nonlocal measures of nonstabilizerness (magic), we study quantum many-body scars near infinite temperature in (1+1)-dimensional Abelian ℤ2 and U(1) lattice gauge theories, both analytically and numerically. We derive an exact closed-form expression for the nonlocal trace distance magic solely from the Schmidt spectrum, reducing the optimization over local unitaries to a finite maximization over stabilizer-compatible Schmidt ranks. We find that scar eigenstates can exhibit extensive global magic despite their anomalously low entanglement, while retaining anomalously large nonlocal magic compared with ergodic states. We further show that constrained Hilbert spaces can generate irreducible nonlocal magic through stabilizer-incompatible Schmidt ranks, even for a flat entanglement spectrum.
Related
- Nonlocal Magic Spreading in Many-body Quantum Dynamics: From Chaotic Evolution to Quasi-particle Picture in Integrable Models
- Nonlocal Magic across the Many-Body Localization Crossover
- Symmetry protected quantum many body scars through half-gauging
- Constrained dissipation and the lifetime of quantum many-body scars
- Dissipative Quantum Battery from Many-Body Scars
BibTeX
@misc{ebner2026global,
title = {{Global and nonlocal magic of quantum many-body scars}},
author = {Lukas Ebner and Giovanni Cataldi and Kaidi Xu and Jad C. Halimeh and Emanuele Tirrito},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.00129},
eprint = {2610.00129},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.00129},
}
RIS
TY - UNPB
TI - Global and nonlocal magic of quantum many-body scars
AU - Lukas Ebner
AU - Giovanni Cataldi
AU - Kaidi Xu
AU - Jad C. Halimeh
AU - Emanuele Tirrito
PY - 2026
DA - 2026/10/01
PB - arXiv
DO - 10.48550/arxiv.2610.00129
UR - https://arxiv.org/abs/2610.00129
AB - Nonergodic features of chaotic quantum many-body systems are commonly characterized through local observables, fidelity, and entanglement entropy. Here, using global and nonlocal measures of nonstabilizerness (magic), we study quantum many-body scars near infinite temperature in (1+1)-dimensional Abelian ℤ_2 and U(1) lattice gauge theories, both analytically and numerically. We derive an exact closed-form expression for the nonlocal trace distance magic solely from the Schmidt spectrum, reducing the optimization over local unitaries to a finite maximization over stabilizer-compatible Schmidt ranks. We find that scar eigenstates can exhibit extensive global magic despite their anomalously low entanglement, while retaining anomalously large nonlocal magic compared with ergodic states. We further show that constrained Hilbert spaces can generate irreducible nonlocal magic through stabilizer-incompatible Schmidt ranks, even for a flat entanglement spectrum.
ER -