2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/26666The housekeeping heat $Q\hk$ is the dissipated heat necessary to maintain the violation of detailed balance in nonequilibrium steady states. By analyzing the evolution of its probability distribution, we prove an integral fluctuation theorem $\mean{\exp[-βQ\hk]}=1$ valid for arbitrary driven transitions between steady states. We discuss Gaussian limiting cases and the difference between the new theorem and both the Hatano-Sasa and the Jarzynski relation.to be published in J. Phys. A: Math. GenStatistical MechanicsSoft Condensed Mattertext