ActivePaths

A library for rare dynamical event sampling in non-equilibrium systems, based on Transition Path Sampling (RTP-TPS) and Variational Path Sampling (VPS).

Features

• Rare Dynamical Event Sampling: Efficiently sample rare events in active matter systems.
• RTP-TPS: Transition Path Sampling for Run-and-Tumble Particles.
• VPS: Variational Path Sampling for computing large deviation functions.
• Analysis Tools: Tools for estimating transition rates and large deviation rate functions.

Installation

pip install activepaths

Usage

RTP-TPS Example (Conceptual)

from activepaths.core import StateTuple
from activepaths.sampling.tps import is_reactive_indicator

# ... (Initialize trajectory and define reactant/product states) ...
# is_reactive = is_reactive_indicator(trajectory, is_reactant, is_product)

VPS Example (Conceptual)

from activepaths.sampling.vps import calculate_stochastic_action

# ... (Define system parameters and trajectory) ...
# action = calculate_stochastic_action(trajectory, mobility, force, dt, T)

Development

To set up the development environment:

git clone https://github.com/USER/activepaths.git
cd activepaths
pip install -e .
pip install -r requirements.txt
pytest

References

This project incorporates research from the following papers:

• Transition-path sampling for Run-and-Tumble particles Thomas Kiechl, Thomas Franosch, Michele Caraglio arXiv:2411.12368

• Variational path sampling of rare dynamical events Aditya N. Singh, Avishek Das, David T. Limmer arXiv:2502.01852