Effective temperature of active matter
Résumé
We follow the dynamics of an ensemble of interacting self-propelled particles in contact with an equilibrated thermal bath. We find that the fluctuation-dissipation relation allows for the definition of an effective temperature that is compatible with the results obtained using a tracer particle as a thermometer. The effective temperature takes a higher value than the temperature of the bath when the effect of the motors is not correlated with the structural rearrangements they induce. Instead, it takes a slightly lower value than the environmental temperature when susceptible motors are used.