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arXiv · 2601.02471

Gaussian time-translation covariant operations: structure, implementation, and thermodynamics

Xueyuan Hu·Lea Lautenbacher·Giovanni Spaventa·Martin B. Plenio·Nelly H. Y. Ng·Jeongrak Son
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Abstract

Time-translation symmetry strongly constrains physical dynamics, yet systematic characterization for continuous-variable systems lags behind its discrete-variable counterpart. We close this gap by providing a rigorous classification of Gaussian quantum operations that are covariant under time translations, termed Gaussian covariant operations. We show that several key results known for discrete-variable covariant operations break down in the Gaussian optical setting: discrepancies arise in physical and thermodynamic implementation, in the extensivity of asymmetry, and in catalytic advantages. Our results provide comprehensive mathematical and operational toolkits for Gaussian covariant operations, including a peculiar pair of asymmetry measures that are completely non-extensive. Our findings also reveal surprising consequences of the interplay among symmetry, Gaussianity, and thermodynamic constraints, suggesting that real-world scenarios with multiple constraints have a rich structure not accessible from examining individual constraints separately.

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Xueyuan Hu, Lea Lautenbacher, Giovanni Spaventa, Martin B. Plenio, Nelly H. Y. Ng, Jeongrak Son. 2026-01-05. Gaussian time-translation covariant operations: structure, implementation, and thermodynamics. https://doi.org/10.1103/9kmm-52nx

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