UPON 2026 Special Sessions
SS1: Stochastic Thermodynamics
SS1 Chair: Léopold Van Brandt (UCLouvain, Belgium)
Stochastic thermodynamics aims to extend the laws of conventional thermodynamics to situations in which random fluctuations are non-negligible, both in and out of equilibrium. It is a relatively recent theory, born in the late 90’. The theoretical framework is especially useful in describing nonlinear system operating out of (and possibly far from) equilibrium. Important examples include nanoscale electron devices (either in classical or quantum regime), but are not limited to these since many applications can be found in other fields like chemistry or biology. From first principles (notably the local detailed balance consequent to the microscopic reversibility), one can derive fundamental relations (for instance, uncertainty relations) on the dissipation, statistical moments of fluctuations (e.g. white noise in nonlinear devices) and of entropy production (associated to any type of “flow” in response to a “force” in a physical and possibly complex system); some of them are reported to have predictive virtues.
As part of UPoN 2026, this special session on stochastic thermodynamics calls for contributions (with or without publication in the conference proceeding) showing application of the theory to physical systems that are intrinsically noisy.
SS2: Noise in Gravitational-Wave Detectors: Sources, Mitigation, and Open Problems
SS2 Chair: Vincenzo Dattilo (EGO, European Gravitational Observatory )
Gravitational-wave detectors represent some of the most sensitive measurement devices ever built, operating at the boundary between the physical limits imposed by fundamental noise and practical noise sources arising from complex instruments embedded in real environments. At these extreme levels of sensitivity, noise is not merely a technical limitation but an intrinsic aspect of the measurement process, shaping both detector performance and experimental strategies.
This special session focuses on the characterization, modeling, and mitigation of noise, which remains a central and open challenge in gravitational-wave science. Understanding and mitigating noise is essential for improving detector sensitivity and stability, as well as for identifying realistic paths toward performance gains.
Contributions are solicited on topics including, but not limited to: fundamental noise mechanisms such as quantum noise in optical readout systems, thermal noise in optical components, coatings, mechanical structures, control-related, and suspension systems, as well as seismic and Newtonian noise. We also welcome studies of environmental and instrumental disturbances, including acoustic, magnetic, and anthropogenic noise, and investigations of how these effects couple into the detector output and limit achievable sensitivity.
The session aims to encourage discussion on fundamental limits imposed by noise, including trade-offs between different noise sources and the constraints they place on detector design and operation. Improving performance in one frequency band often leads to the emergence of previously subdominant noise contributions in another, highlighting the need for a global and physically grounded understanding of the detector noise budget.
By emphasizing unresolved questions at the interface between fundamental noise limits, instrumental design, control strategies, and environmental conditions, this special session highlights noise as a central challenge in gravitational-wave detection and as a key driver for future advances. The session is intended to provide a focused forum for exchanging ideas, discussing open problems, and fostering cross-disciplinary dialogue, in full alignment with the goals and spirit of UPON 2026.