



01580nas a2200145   4500008004100000245009700041210006900138260001400207520107900221100002101300700002501321700002301346700002801369856003701397       2023                        eng d00aWhat happens to entropy production when conserved quantities fail to commute with each other0 aWhat happens to entropy production when conserved quantities fai  c5/24/20233 a<p>We extend entropy production to a deeply quantum regime involving noncommuting conserved quantities. Consider a unitary transporting conserved quantities (&quot;charges&quot;) between two systems initialized in thermal states. Three common formulae model the entropy produced. They respectively cast entropy as an extensive thermodynamic variable, as an information-theoretic uncertainty measure, and as a quantifier of irreversibility. Often, the charges are assumed to commute with each other (e.g., energy and particle number). Yet quantum charges can fail to commute. Noncommutation invites generalizations, which we posit and justify, of the three formulae. Charges&#39; noncommutation, we find, breaks the formulae&#39;s equivalence. Furthermore, different formulae quantify different physical effects of charges&#39; noncommutation on entropy production. For instance, entropy production can signal contextuality - true nonclassicality - by becoming nonreal. This work opens up stochastic thermodynamics to noncommuting - and so particularly quantum - charges.</p>1 aUpadhyaya, Twesh1 aBraasch, William, F.1 aLandi, Gabriel, T.1 aHalpern, Nicole, Yunger  uhttps://arxiv.org/abs/2305.15480