Description
Systems with disparate timescales are ubiquitous in physics and biology. Efficient modeling dictates to restrict the description to the slower processes and not to fully resolve the faster ones. I will discuss this general issue in stochastic systems with two well separated timescales. In particular, I will address the behavior of thermodynamics upon changing the level of resolution. I will show how for non-equilibrium systems, under quite general conditions, properties of the fast dynamics still affect thermodynamics on the slower scales therefore compromising a description of the full system in terms of slow variables only. This feature is due to a symmetry breaking accompanying the change of resolution in the description. In this respect, it is reminiscent of physical anomalies such as the viscous dissipative anomaly and quantum anomalies.
In closing, I will give two relevant examples concerning Brownian motion and a simple biochemical network.