Dynamic origin of long-range concentration correlations in nonequilibrium diffusion

Determine the dynamical mechanism by which nonequilibrium long-range correlations of concentration fluctuations emerge in diffusion processes (e.g., solute in solvent or colloids), and develop a predictive theory that quantitatively accounts for their formation and scaling.

Background

Empirically, nonequilibrium diffusive systems display long-range correlations in concentration fluctuations, but the microscopic dynamical pathway that generates and sustains these correlations is not established.

A resolution requires linking observed steady-state correlations to underlying transport, interactions, and possible hydrodynamic couplings within a nonequilibrium fluctuation framework.

References

Finally, it is experimentally well-established that nonequilibrium long-range correlations of concentration fluctuations appear in diffusions of a solute in a solvent or of colloids. It remains unknown how such correlations are established dynamically.

— What is nonequilibrium?  (2601.16716 - Maes, 23 Jan 2026) in Section "Nonequilibrium (open) problems", Item 5 (Derivation of induced forces or interactions)