University of Cambridge > > Theoretical Physics Colloquium > Dynamical Field Theories without Detailed Balance

Dynamical Field Theories without Detailed Balance

Add to your list(s) Download to your calendar using vCal

If you have a question about this talk, please contact Ronak M Soni.

Many condensed matter problems, such as ordering of a classical ferromagnet or fluid-fluid phase separation, are described by dynamical field theories in which a scalar field obeys a noisy gradient flow governed by a quartic effective potential. These theories are called Model A and Model B for the cases of a non-conserved and conserved scalar, respectively. Traditionally, such models are constructed to obey detailed balance, so that the system evolves to the Boltzmann distribution, giving time-reversible fluctuations at stationarity. Reaching the equilibrium state can be nontrivial however: starting from a metastable uniform initial condition, it requires an instanton to nucleates a droplet large enough to then grow spontaneously. In recent years, attention has shifted to systems without detailed balance, whose stationary states are non-Boltzmann and involve continuous entropy production with time-asymmetric fluctuations. (One example is the study of phase separation among self-propelled particles such as swimming bacteria.) To describe such cases, we have recently introduced variants of Models A and B that break detailed balance explicitly. I will outline some of the qualitative and quantitative novelties that arise in the critical phenomena, steady states, and instantons of these new theories.

This talk is part of the Theoretical Physics Colloquium series.

Tell a friend about this talk:

This talk is included in these lists:

Note that ex-directory lists are not shown.


© 2006-2024, University of Cambridge. Contact Us | Help and Documentation | Privacy and Publicity