Related Experiment Video
Updated: Jan 30, 2026

Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster
Published on: January 25, 2013
Active escape dynamics: The effect of persistence on barrier crossing
Lorenzo Caprini1, Umberto Marini Bettolo Marconi2, Andrea Puglisi3
1Gran Sasso Science Institute (GSSI), Via. F. Crispi 7, 67100 L'Aquila, Italy.
Abstract:
We study a system of non-interacting active particles, propelled by colored noises, characterized by an activity time τ, and confined by a double-well potential. A straightforward application of this system is the problem of barrier crossing of active particles, which has been studied only in the limit of small activity. When τ is sufficiently large, equilibrium-like approximations break down in the barrier crossing region. In the model under investigation, it emerges as a sort of "negative temperature" region, and numerical simulations confirm the presence of non-convex local velocity distributions. We propose, in the limit of large τ, approximate equations for the typical trajectories which successfully predict many aspects of the numerical results. The local breakdown of detailed balance and its relation with a recent definition of non-equilibrium heat exchange is also discussed.
Related Concept Videos
Escape Velocity
To calculate the escape velocity, it is assumed that no energy is lost to any frictional forces. In practice, a satellite...
Crossing Over
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
Crossing Over
Escape Velocities of Gases
Monohybrid Crosses
Cross-Sectional Research

