Predicting symmetries of quantum dynamics with optimal samples

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Hayashi, Masahito, Chen, Yu-Ao, Zhu, Chenghong, Wang, Xin
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915135003557888
author Hayashi, Masahito
Chen, Yu-Ao
Zhu, Chenghong
Wang, Xin
author_facet Hayashi, Masahito
Chen, Yu-Ao
Zhu, Chenghong
Wang, Xin
contents Identifying symmetries in quantum dynamics, such as identity or time-reversal invariance, is a crucial challenge with profound implications for quantum technologies. We introduce a unified framework combining group representation theory and subgroup hypothesis testing to predict these symmetries with optimal efficiency. By exploiting the inherent symmetry of compact groups and their irreducible representations, we derive an exact characterization of the optimal type-II error (failure probability to detect a symmetry), offering an operational interpretation for the quantum max-relative entropy. In particular, we prove that parallel strategies achieve the same performance as adaptive or indefinite-causal-order protocols, resolving debates about the necessity of complex control sequences. Applications to the singleton group, maximal commutative group, and orthogonal group yield explicit results: for predicting the identity property, Z-symmetry, and T-symmetry of unknown qubit unitaries, with zero type-I error and type-II error bounded by $δ$, we establish the explicit optimal sample complexity which scales as $\mathcal{O}(δ^{-1/3})$ for identity testing and $\mathcal{O}(δ^{-1/2})$ for T/Z-symmetry testing. These findings offer theoretical insights and practical guidelines for efficient unitary property testing and symmetry-driven protocols in quantum information processing.
format Preprint
id arxiv_https___arxiv_org_abs_2502_01464
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Predicting symmetries of quantum dynamics with optimal samples
Hayashi, Masahito
Chen, Yu-Ao
Zhu, Chenghong
Wang, Xin
Quantum Physics
Information Theory
Identifying symmetries in quantum dynamics, such as identity or time-reversal invariance, is a crucial challenge with profound implications for quantum technologies. We introduce a unified framework combining group representation theory and subgroup hypothesis testing to predict these symmetries with optimal efficiency. By exploiting the inherent symmetry of compact groups and their irreducible representations, we derive an exact characterization of the optimal type-II error (failure probability to detect a symmetry), offering an operational interpretation for the quantum max-relative entropy. In particular, we prove that parallel strategies achieve the same performance as adaptive or indefinite-causal-order protocols, resolving debates about the necessity of complex control sequences. Applications to the singleton group, maximal commutative group, and orthogonal group yield explicit results: for predicting the identity property, Z-symmetry, and T-symmetry of unknown qubit unitaries, with zero type-I error and type-II error bounded by $δ$, we establish the explicit optimal sample complexity which scales as $\mathcal{O}(δ^{-1/3})$ for identity testing and $\mathcal{O}(δ^{-1/2})$ for T/Z-symmetry testing. These findings offer theoretical insights and practical guidelines for efficient unitary property testing and symmetry-driven protocols in quantum information processing.
title Predicting symmetries of quantum dynamics with optimal samples
topic Quantum Physics
Information Theory
url https://arxiv.org/abs/2502.01464