Publications (36)
Fisher zeroes and the fluctuations of the spectral form factor of chaotic systems
Guy Bunin, Laura Foini, Jorge Kurchan
The spectral form factor of quantum chaotic systems has the familiar `ramp plateau' form. Techniques to determine its form in the semiclassical or the thermodynamic limit have…
Transport-induced correlations in weakly interacting systems
Guy Bunin, Yariv Kafri, Vivien Lecomte +2
We study spatial correlations in the transport of energy between two baths at different temperatures. To do this, we introduce a minimal model in which energy flows from one bath t…
Numerical implementation of dynamical mean field theory for disordered systems: application to the Lotka-Volterra model of ecosystems
Felix Roy, Giulio Biroli, Guy Bunin +1
Dynamical mean field theory (DMFT) is a tool that allows to analyze the stochastic dynamics of interacting degrees of freedom in terms of a self-consistent -body problem. In…
A model with Darwinian dynamics on a rugged landscape
Tommaso Brotto, Guy Bunin, Jorge Kurchan
We discuss the population dynamics with selection and random diffusion, keeping the total population constant, in a fitness landscape associated with Constraint Satisfaction, a par…
Large deviations in boundary-driven systems: Numerical evaluation and effective large-scale behavior
Guy Bunin, Yariv Kafri, Daniel Podolsky
We study rare events in systems of diffusive fields driven out of equilibrium by the boundaries. We present a numerical technique and use it to calculate the probabilities of rare…
Coalescence Model for Crumpled Globules Formed in Polymer Collapse
Guy Bunin, Mehran Kardar
The rapid collapse of a polymer, due to external forces or changes in solvent, yields a long-lived `crumpled globule.' The conjectured fractal structure shaped by hierarchical coll…
Dynamics of Energy Fluctuations in Equilibrating and Driven-Dissipative Systems
Guy Bunin, Yariv Kafri
When two isolated system are brought in contact, they relax to equilibrium via energy exchange. In another setting, when one of the systems is driven and the other is large, the fi…
Quenched complexity of equilibria for asymmetric Generalized Lotka-Volterra equations
Valentina Ros, Felix Roy, Giulio Biroli +1
We consider the Generalized Lotka-Volterra system of equations with all-to-all, random asymmetric interactions describing high-dimensional, very diverse and well-mixed ecosystems.…
Local and collective transitions in sparsely-interacting ecological communities
Stav Marcus, Ari M. Turner, Guy Bunin
Interactions in natural communities can be highly heterogeneous, with any given species interacting appreciably with only some of the others, a situation commonly represented by sp…
Environmental engineering is an emergent feature of diverse ecosystems and drives community structure
Madhu Advani, Guy Bunin, Pankaj Mehta
A central question in ecology is to understand the ecological processes that shape community structure. Niche-based theories have emphasized the important role played by competitio…
Extending the applicability of Thermal Dynamics to Evolutionary Biology
Tommaso Brotto, Guy Bunin, Jorge Kurchan
In the past years, a remarkable mapping has been found between the dynamics of a population of M individuals undergoing random mutations and selection, and that of a single system…
Frequency-dependent fluctuation-dissipation relations in granular gases
Guy Bunin, Yair Shokef, Dov Levine
The Green-Kubo relation for two models of granular gases is discussed. In the Maxwell model in any dimension, the effective temperature obtained from the Green-Kubo relation is sho…
Can endogenous fluctuations persist in high-diversity ecosystems?
Felix Roy, Matthieu Barbier, Giulio Biroli +1
When can complex ecological interactions drive an entire ecosystem into a persistent non-equilibrium state, where species abundances keep fluctuating without going to extinction? W…
Many-species ecological fluctuations as a jump process from the brink of extinction
Thibaut Arnoulx de Pirey, Guy Bunin
Highly-diverse ecosystems exhibit a broad distribution of population sizes and species turnover, where species at high and low abundances are exchanged over time. We show that thes…
When can few-species models describe dynamics within a complex community?
Stav Marcus, Guy Bunin
Dynamics of species' abundances in ecological communities are often described using models that only account for a few species. It is not clear when and why this would be possible,…
Local and extensive fluctuations in sparsely-interacting ecological communities
Stav Marcus, Ari M Turner, Guy Bunin
Ecological communities with many species can be classified into dynamical phases. In systems with all-to-all interactions, a phase where a fixed point is always reached and a dynam…
Dynamical persistence in resource-consumer models
Itay Dalmedigos, Guy Bunin
We show how highly-diverse ecological communities may display persistent abundance fluctuations, when interacting through resource competition and subjected to migration from a spe…
Topological Constraints in Directed Polymer Melts
Pablo Serna, Guy Bunin, Adam Nahum
Polymers in a melt may be subject to topological constraints, as in the example of unlinked polymer rings. How to do statistical mechanics in the presence of such constraints remai…
Marginally Stable Equilibria in Critical Ecosystems
Giulio Biroli, Guy Bunin, Chiara Cammarota
In this work we study the stability of the equilibria reached by ecosystems formed by a large number of species. The model we focus on are Lotka-Volterra equations with symmetric r…
Fixed points of Boolean networks with sparse connections
Stav Marcus, Ari M. Turner, Guy Bunin +1
We study fixed points of cellular automata with sites on random sparse graphs. In the large limit such models are known to exhibit phase transitions, from a ``frozen'' phas…
Fluctuation-dissipation relations in driven dissipative systems
Yair Shokef, Guy Bunin, Dov Levine
Exact theoretical results for the violation of time dependent fluctuation-dissipation relations in driven dissipative systems are presented. The ratio of correlation to delayed res…
Population aging through survival of the fit and stable
Tommaso Brotto, Guy Bunin, Jorge Kurchan
Motivated by the wide range of known self-replicating systems, some far from genetics, we study a system composed by individuals having an internal dynamics with many possible stat…
Singularities in Large Deviation Functionals of Bulk-Driven Transport Models
Avi Aminov, Guy Bunin, Yariv Kafri
The large deviation functional of the density field in the weakly asymmetric exclusion process with open boundaries is studied using a combination of numerical and analytical metho…
A Continuum Theory for Unstructured Mesh Generation in Two Dimensions
Guy Bunin
A continuum description of unstructured meshes in two dimensions, both for planar and curved surface domains, is proposed. The meshes described are those which, in the limit of an…
Universal energy fluctuations in thermally isolated driven systems
Guy Bunin, Luca D'Alessio, Yariv Kafri +1
When an isolated system is brought in contact with a heat bath its final energy is random and follows the Gibbs distribution -- a cornerstone of statistical physics. The system's e…
Non differentiable large-deviation functionals in boundary-driven diffusive systems
Guy Bunin, Yariv Kafri, Daniel Podolsky
We study the probability of arbitrary density profiles in conserving diffusive fields which are driven by the boundaries. We demonstrate the existence of singularities in the large…
Extinctions of coupled populations, and rare-event dynamics under non-Gaussian noise
Tal Agranov, Guy Bunin
The survival of natural populations may be greatly affected by environmental conditions that vary in space and time. We look at a population residing in two locations (patches) cou…
Adaptation to time-varying environments in a reaction-diffusion model
Olivier Rivoire, Guy Bunin
We present a spatially-extended system of chemical reactions exhibiting adaptation to time-dependent influxes of reactants. Here adaptation is defined as improved reproductive succ…
Cusp singularities in boundary-driven diffusive systems
Guy Bunin, Yariv Kafri, Daniel Podolsky
Boundary driven diffusive systems describe a broad range of transport phenomena. We study large deviations of the density profile in these systems, using numerical and analytical m…
Interaction patterns and diversity in assembled ecological communities
Guy Bunin
The assembly of ecological communities from a pool of species is central to ecology, but the effect of this process on properties of community interaction networks is still largely…
Evolutionary features in a minimal physical system: diversity, selection, growth, inheritance, and adaptation
Guy Bunin, Olivier Rivoire
We present a simple physical model that recapitulates several features of biological evolution, while being based only on thermally-driven attachment and detachment of elementary b…
Extinctions as a vestige of instability: the geometry of stability and feasibility
Stav Marcus, Ari M. Turner, Guy Bunin
Species coexistence is a complex, multifaceted problem. At an equilibrium, coexistence requires two conditions: stability under small perturbations; and feasibility, meaning all sp…
Critical behavior of a phase transition in the dynamics of interacting populations
Thibaut Arnoulx de Pirey, Guy Bunin
Many-variable differential equations with random coefficients provide powerful models for the dynamics of many interacting species in ecology. These models are known to exhibit a d…
Generalized Lotka-Volterra equations with random, non-reciprocal interactions: the typical number of equilibria
Valentina Ros, Felix Roy, Giulio Biroli +2
We compute the typical number of equilibria of the Generalized Lotka-Volterra equations describing species-rich ecosystems with random, non-reciprocal interactions using the replic…
Towards Unstructured Mesh Generation Using the Inverse Poisson Problem
Guy Bunin
A novel approach to unstructured quadrilateral mesh generation for planar domains is presented. Away from irregular vertices, the resulting meshes have the properties of nearly con…
Aging by near-extinctions in many-variable interacting populations
Thibaut Arnoulx de Pirey, Guy Bunin
Models of many-species ecosystems, such as the Lotka-Volterra and replicator equations, suggest that these systems generically exhibit near-extinction processes, where population s…