| 04/2025 Neural mechanisms of predictive processing: a collaborative community experiment through the OpenScope program Ido Aizenbud et al. This review synthesizes advances in predictive processing within the sensory cortex. Predictive processing theorizes that the brain continuously predicts sensory inputs, refining neuronal responses by highlighting prediction errors. We identify key computational primitives, such as stimulus adaptation, dendritic computation, excitatory/inhibitory balance and hierarchical processing, as central to … |
| 03/2025 Pseudo-giant number fluctuations and nematic order in microswimmer suspensions Ismail El Korde et al. Giant number fluctuations (GNFs), whereby the standard deviation $\Delta N$ in the local number of particles $\langle N \rangle$ grows faster than $\sqrt{\langle N \rangle}$, are a hallmark property of dry active matter systems with orientational order, such as a collection of granular particles on a vibrated plate. This contrasts with momentum-conserving ("wet") active matter systems, s … |
| 03/2025 Phase Diagram of the Non-Reciprocal Cahn-Hilliard Model and the Effects of Symmetry Martin Kjøllesdal Johnsrud et al. Interactions between active particles may be non-reciprocal, breaking action-reaction symmetry and leading to novel physics not seen in equilibrium systems. In this work, we study the phase diagram for the non-reciprocal Cahn-Hilliard (NRCH) model with different types of symmetry — discrete and continuous — and examine the effects of non-reciprocity on phase separation. The models are analyzed b … |
| 03/2025 Equilibrium phases and phase transitions in multicritical magnetic polymers Alberto Raiola et al. Magnetic polymers are examples of composite soft materials in which the competition between the large configurational entropy of the soft substrate (polymer) and the magnetic interaction may give rise to rich equilibrium phase diagrams as well as non-standard critical phenomena. Here, we study a self-avoiding walk model decorated by Ising spins of value $0$ and $\pm 1$ that interact according to a … |
| 02/2025 Hydrodynamic stresses in a multi-species suspension of active Janus colloids Gennaro Tucci et al. A realistic description of active particles should include interactions with the medium, commonly a momentum-conserving simple fluid, in which they are suspended. In this work, we consider a multi-species suspension of self-diffusiophoretic Janus colloids interacting via chemical and hydrodynamic fields. Through a systematic coarse-graining of the microscopic dynamics, we calculate the multi-compo … |
| 02/2025 Fluctuation Dissipation Relations for the Non-Reciprocal Cahn-Hilliard Model Martin Kjøllesdal Johnsrud et al. Recent results demonstrate how deviations from equilibrium fluctuation-dissipation theorem can be quantified for active field theories by deriving exact fluctuations dissipation relations that involve the entropy production [M. K. Johnsrud and R. Golestanian, arXiv:2409.14977]. Here we develop and employ diagrammatic tools to perform perturbative calculations for a paradigmatic active field theory … |
| 01/2025 Sensitive particle shape dependence of growth-induced mesoscale nematic structure Jonas Isensee et al. Directed growth, anisotropic cell shapes, and confinement drive self-organization in multicellular systems. We investigate the influence of particle shape on the distribution and dynamics of nematic microdomains in a minimal in-silico model of proliferating, sterically interacting particles, akin to colonies of rod-shaped bacteria. By introducing continuously tuneable tip variations around a commo … |
| 01/2025 Physics of droplet regulation in biological cells David Zwicker et al. Droplet formation has emerged as an essential concept for the spatiotemporal organisation of biomolecules in cells. However, classical descriptions of droplet dynamics based on passive liquid-liquid phase separation cannot capture the complex situations inside cells. This review discusses three general aspects that are crucial in cells: (i) biomolecules are diverse and individually complex, implyi … |
| 01/2025 Stochastic bubble dynamics in phase-separated scalar active matter Mingqi Yan et al. In ABP systems, phase separation is accompanied by the emergence of vapor bubbles within liquid domains. Using large-scale particle-based simulations, we study the stochastic dynamics of these bubbles and find that most nucleate, grow, and dissolve within liquid domains. We show that their area dynamics can be described by a Langevin equation with a constant negative drift and noise proportional t … |
| 01/2025 Enhanced condensate fluidity in modified patchy particle models Alena Taskina et al. Biomolecular condensates are formed via liquid-liquid phase separation of proteins, often together with nucleic acids, typically driven by interactions between low-affinity binding sites. The computational study of such condensates that accounts both for the droplet-scale fluid behavior and the internal structure of the condensate requires coarse-grained models. Recently, patchy particle models, r … |