Workshop talk
When is hydrodynamic noise really noise? Detailed balance and positivity in fluctuating hydrodynamics
- Presenter
- Andrea Amoretti
- Conference
- FRAME2026 - Fluctuations and RAndomness in Many-body Evolution
- Conference dates
- 16-18 September 2026
- Presentation date
- 17 September 2026
- Time
- 12:20-12:40
- Venue
- Institut Pascal, Université Paris-Saclay, Orsay, France
Abstract
Schwinger-Keldysh effective theories of dissipative hydrodynamics contain non-Gaussian noise couplings that are constrained by symmetry but need not define a positive probability distribution. Requiring the noise sector to admit a genuine probabilistic interpretation imposes additional, sharp inequalities between cumulants. The resulting bounds can be saturated by explicit positive distributions and provide a direct way of deciding when a formal stochastic effective theory can actually be sampled as noise.
Summary based on the related paper; the FRAME2026 programme lists the talk but does not publish a separate abstract.
Workshop talk
Fluctuation-dissipation beyond hydrodynamics: nonlinear Maxwell-Cattaneo in the Schwinger-Keldysh formalism
- Presenter
- Daniel K. Brattan
- Conference
- FRAME2026 - Fluctuations and RAndomness in Many-body Evolution
- Conference dates
- 16-18 September 2026
- Presentation date
- 18 September 2026
- Time
- 15:00-15:20
- Venue
- Institut Pascal, Université Paris-Saclay, Orsay, France
Abstract
We determine when nonlinear Maxwell-Cattaneo charge transport admits a local Gaussian Schwinger-Keldysh embedding with a modified dynamical KMS symmetry. Treating the additional vector mode as intrinsically dissipative changes the entropy-current analysis: hydrostatics no longer fixes every allowed improvement, while KMS invariance supplies further constraints that are invisible at the level of hydrodynamics alone. The resulting construction gives a stochastic quasihydrodynamic interpretation of charge transport beyond the purely hydrodynamic pole.
Summary based on the related paper; the FRAME2026 contribution page does not publish a separate abstract.
