Gated first-passage processes, where completion depends on both hitting a target and satisfying additional constraints, are prevalent across various fields. Despite their significance, analytical solutions to basic problems remain unknown, e.g. the detection time of a diffusing particle by a gated interval, disk, or sphere. We elucidate the challenges posed by continuous gated first-passage processes and present a renewal framework to overcome them.

Congratulations to Bara Levit for winning the prestigious Colton Ph.D. Scholarship. 

Congratulations to Itamar Shitrit for winning the first place in the poster competition of the annual meeting of the Israel Physics Society 2024. The prize was awarded for his research – Sokoban percolation on the Bethe lattice – which was carried out in collaboration with Ofek Lauber. 

'With persistence, a drop of water hollows out the stone' goes the ancient Greek proverb. Yet, canonical percolation models do not account for interactions between a moving tracer and its environment. Recently, we have introduced the Sokoban model, which differs from this convention by allowing a tracer to push single obstacles that block its path. To test how this newfound ability affects percolation, we present an exact solution of the Sokoban model on the Bethe lattice. 

The escape dynamics of sticky particles from textured surfaces is poorly understood despite its importance to various scientific and technological domains. We address this challenge by providing first analytical expressions for the escape time of adsorbates from prevalent surface topographies, including holes/pits, pillars, and grooves. 

The Montroll-Weiss continuous time random walk has found numerous applications due its ease of use and ability to describe both regular and anomalous diffusion. Yet, despite its broad applicability and generality, the model cannot account for effects coming from random diffusivity fluctuations, which have been observed in the motion of asset prices and molecules. To bridge this gap, we introduce a doubly stochastic version of the model in which waiting times between jumps are replaced with a fluctuating jump rate. 

We study the motion of a self-propelled bristle robot that moves randomly within an arena filled with obstacles. We show that trails created by the robot give rise to a form of environmental memory that facilitates search with home returns by increasing the effective diffusion coefficient of the robot. Numerical simulations and theoretical estimates designed to capture the essential physics of the experiment support our conclusions and indicate that these are not limited to the particular system studied herein.

Infrequent Metadynamics is a popular method to obtain the rates of long time-scale processes from accelerated molecular dynamics simulations. We propose to improve kinetics inference in this method by focusing on short time scales. We demonstrate the new inference scheme for a model system and two molecular systems. We show an improved trade-off between speedup and accuracy at no additional computational cost, especially when employing suboptimal collective variables.

We present a robust and general approach to bacterial identification based on their unique enzymatic activity profiles. This method delivers results within 90 minutes, utilizing an array of highly sensitive and enzyme-selective chemiluminescent probes.  The method opens new avenues for characterizing and identifying pathogens in research, clinical, and industrial applications.