Christian Maes – KU Leuven
Wednesday, October 15th, 2025
Zoom opens: 10:30AM DST
Seminar begins: 10:45AM DST
Kinetics of nonequilibrium response: negative heat capacity and negative drag
We discuss two aspects of extended fluctuation-dissipation relations for steady nonequilibrium regimes.
Negative heat capacities show the separation, in fact, an anticorrelation between a Clausius-like entropy (related to heat) and a Boltzmann-like entropy (related to occupation statistics). Secondly, initially passive probes coupled to an active medium may pick up a negative linear drag after which they stabilize in a regime where they inherit the persistence of the active particles in the medium.
References:
arXiv:2505.18665v2 [cond-mat.stat-mech], joint work with Aaron Beyen and Jihui Pei;
arXiv:2504.03210v2 [cond-mat.stat-mech], joint work with Jihui Pei;
Lander Bogers, Faezeh Khodabandehlou and Christian Maes, Negative specific heats: where Clausius and Boltzmann entropies separate. Physical Chemistry Chemical Physics 27,15009-15023 (2025).