Aishani Ghoshal

(presenting on November 12, 2025)

Challenges in Thermodynamic and Diffusion Inference from Finite-Resolution Observations

Abstract

All living systems operate far from thermodynamic equilibrium, and their functions are constrained by thermodynamic principles. Dissipation, a key thermodynamic quantity, not only measures the degree of nonequilibrium in a process but is also intrinsically linked to the efficiency of irreversible processes. Accurately estimating dissipation is therefore crucial for understanding the performance of biological nanomachines, which function reliably even in noisy environments, as well as for designing efficient artificial nanomachines.
However, estimating dissipation is challenging because it requires knowledge of all driven degrees of freedom, which is typically inaccessible due to the finite spatiotemporal resolution of experiments. This limitation makes dissipation estimation particularly difficult in partially observed systems. I will present examples showing how lower bounds on dissipation can be inferred from observed dynamics. [1] Moreover, limited spatiotemporal resolution not only obscures the nonequilibrium nature of the underlying process but can also lead to incorrect inferences about the underlying diffusive dynamics. I will discuss how measurement artifacts affect diffusion inference and offer practical considerations for accurately estimating diffusion parameters. [2]

[1] A Ghosal et al., Phys. Chem. Chem. Phys. 24, 24021-24031 (2022); A Ghosal et al., J. Phys. D: Appl. Phys. 56 254001 (2023); E. Nitzan et al., Phys. Rev. Res. 5, 043251 (2023); U. Kapustin et al., Phys. Rev. Res. 6, 023039 (2024)
[2] A Ghosal et al., bioRxiv 2025.06.12.659344 (2025)

Speaker Bio

Dr. Aishani Ghosal is a staff scientist at Washington University in St. Louis, joining in July 2025 after completing postdoctoral research at Tel Aviv University, the University of Massachusetts Boston, and the University of Illinois Urbana Champaign. She completed her Ph.D. degree on theoretical studies of the non-equilibrium statistical mechanics of colloidal and polymeric systems at the single molecule level at Indian Institute of Science, Bangalore (India). Her work spans stochastic thermodynamics, soft condensed matter, and biophysics, exploring the fundamental principles that govern complex systems.