Dresden 2026 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 38: Active Matter VI (joint session DY/BP)

BP 38.6: Vortrag

Freitag, 13. März 2026, 11:15–11:30, ZEU/0160

Critical Dynamics of Active, Isotropic Systems — •Emir Sezik and Gunnar Pruessner — Imperial College London

A central result of field theory and renormalisation group (RG) is the concept of universality classes. Systems with different microscopic properties display the same physics near a continuous phase transition as they share the same symmetries. In equilibrium critical dynamics, where systems relax to a thermal steady state, Hohenberg and Halperin have provided the authoritative catalogue, which however, does not immediately extend to critical active matter systems. As they display exciting and new phases by their breaking of detailed balance, we have every reason to attempt to identify the relevant terms and to catalogue these non-equilibrium, critical systems. Motivated by this, in this work, we study an active version of Model A by including the relevant terms that are allowed by symmetry in the coarse-grained description. We show that this universality class encompasses diverse systems including spins with vision-cone interactions and Malthusian flocks. Finally, using field-theoretic RG, we perform a 1-loop calculation, approaching the critical point from the disordered regime, and elucidate the effects of activity on the Wilson-Fisher fixed point.

Keywords: Field Theory; Active Matter; Renormalisation Group; Universality Classes; Critical Dynamics