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Thermodynamic uncertainty relation for quantum entropy production.

Domingos S P Salazar¹

¹Unidade de Educação a Distância e Tecnologia, <a href="https://ror.org/02ksmb993">Universidade Federal Rural de Pernambuco</a>, 52171-900 Recife, Pernambuco, Brazil.

Physical Review. E

|August 20, 2024

Summary

This summary is machine-generated.

Researchers derived a new thermodynamic uncertainty relation (TUR) for quantum entropy production. This finding connects quantum and stochastic thermodynamics, offering a lower bound based on observable measurements.

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Area of Science:

Quantum Thermodynamics
Statistical Mechanics
Information Theory

Background:

Entropy production is typically defined using quantum relative entropy in quantum thermodynamics.
Existing thermodynamic uncertainty relations (TURs) apply to classical stochastic systems.

Purpose of the Study:

To derive a quantum version of the thermodynamic uncertainty relation (TUR) for entropy production.
To establish a lower bound for quantum entropy production using measurable quantities.

Main Methods:

Derivation of a lower bound for quantum entropy production.
Introduction of a lower bound for a quantum generalization of chi-squared divergence.
Analysis of the relationship between quantum and classical TURs.

Main Results:

A novel thermodynamic uncertainty relation (TUR) for quantum entropy production was established.
The derived TUR is expressed in terms of the mean and variance of quantum observables.
The result reproduces classical TURs in stochastic thermodynamics when coherence is absent.

Conclusions:

The new quantum TUR provides a fundamental link between quantum measurements and entropy production.
The findings have implications for both quantum and stochastic thermodynamics.
The study highlights the broad applicability of uncertainty relations across different thermodynamic regimes.