English
Related papers

Related papers: Eulerian dynamics with a commutator forcing II: fl…

200 papers

Within a simple model of attractive active Brownian particles, we predict flocking behavior and challenge the widespread idea that alignment interactions are necessary to observe this collective phenomenon. Here, we show that even…

Soft Condensed Matter · Physics 2023-04-19 Lorenzo Caprini , Hartmut Löwen

In this note we continue our study of unidirectional solutions to hydrodynamic Euler alignment systems with strongly singular communication kernels $\phi(x):=|x|^{-(n+\alpha)}$ for $\alpha\in(0,2)$. Here, we consider the critical case…

Analysis of PDEs · Mathematics 2021-05-26 Daniel Lear

We construct a normal form suited to {\it fast driven systems}. We call so systems including actions ${\rm I}$, angles {$\psi$}, and one fast coordinate $y$, moving under the action of a vector--field $N$ depending only on ${\rm I}$ and $y$…

Dynamical Systems · Mathematics 2022-02-24 Qinbo Chen , Gabriella Pinzari

The goal of this note is to study limiting behavior of a self-organized continuous flock evolving according to the 1D hydrodynamic Euler Alignment model. We provide a series of quantitative estimates that show how far the density of the…

Analysis of PDEs · Mathematics 2019-08-15 Trevor M. Leslie , Roman Shvydkoy

Natural flocks (aligned) and swarms (non-aligned) both exhibit features of near-criticality, challenging their treatment as two ends of the same phase transition. We present a model for the aggregation of active individuals, in which their…

Adaptation and Self-Organizing Systems · Physics 2025-11-26 Joao Lizárraga , Marcus de Aguiar

We study a new flocking model which has the versatility to capture the physically realistic qualitative behavior of the Motsch-Tadmor model, while also retaining the entropy law, which lends to a similar 1D global well-posedness analysis to…

Analysis of PDEs · Mathematics 2024-06-14 Roman Shvydkoy , Trevor Teolis

Flocking refers to collective behavior of a large number of interacting entities, where the interactions between discrete individuals produce collective motion on the large scale. We employ an agent-based model to describe the microscopic…

Numerical Analysis · Mathematics 2020-12-23 Zhiping Mao , Zhen Li , George Em Karniadakis

We consider the compressible Euler system for ideal gas flow in the absence of any forces except the internal thermodynamic pressure. In this setting, and in dimensions higher 1, it is known that wave-focusing can drive Euler solutions to…

Analysis of PDEs · Mathematics 2026-04-27 Helge Kristian Jenssen

We consider the evolution of an incompressible two-dimensional perfect fluid as the boundary of its domain is deformed in a prescribed fashion. The flow is taken to be initially steady, and the boundary deformation is assumed to be slow…

Analysis of PDEs · Mathematics 2007-05-23 J. Vanneste , D. Wirosoetisno

Collective motion - or flocking - is an emergent phenomena that underlies many biological processes of relevance, from cellular migrations to animal groups movement. In this work, we derive scaling relations for the fluctuations of the mean…

Soft Condensed Matter · Physics 2023-02-13 Martino Brambati , Giuseppe Fava , Francesco Ginelli

Confining in space the equilibrium fluctuations of statistical systems with long-range correlations is known to result into effective forces on the boundaries. Here we demonstrate the occurrence of Casimir-like forces in the non-equilibrium…

Soft Condensed Matter · Physics 2024-03-04 Giuseppe Fava , Andrea Gambassi , Francesco Ginelli

When interacting motile units self-organize into flocks, they realize one of the most robust ordered state found in nature. However, after twenty five years of intense research, the very mechanism controlling the ordering dynamics of both…

Soft Condensed Matter · Physics 2021-10-04 Amélie Chardac , Ludwig A. Hoffmann , Yoann Poupart , Luca Giomi , Denis Bartolo

In a system of noisy self-propelled particles with interactions that favor directional alignment, collective motion will appear if the density of particles increases beyond a certain threshold. In this paper, we argue that such a threshold…

Soft Condensed Matter · Physics 2010-03-29 Chiu Fan Lee

We examine in the context of general relativity the dynamics of a spatially flat Robertson-Walker universe filled with a classical minimally coupled scalar field \phi of exponential potential ~ e^{-\mu\phi} plus pressureless baryonic…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. Kehagias , G. Kofinas

We study the hydrodynamic description of collective dynamics driven by velocity {\it alignment}. It is known that such Euler alignment systems must flock towards a limiting ``flocking'' velocity, provided their solutions remain globally…

Analysis of PDEs · Mathematics 2025-06-24 Eitan Tadmor

This paper considers a group of mobile autonomous agents moving in Euclidean space with point mass dynamics. We introduce a set of coordination control laws that enable the group to generate the desired stable flocking motion. The control…

Statistics Theory · Mathematics 2007-06-13 Long Wang

We consider correlators for the flux of energy and charge in the background of operators with large global $U(1)$ charge in conformal field theory (CFT). It has recently been shown that the corresponding Euclidean correlators generically…

High Energy Physics - Theory · Physics 2023-09-27 Eren Firat , Alexander Monin , Riccardo Rattazzi , Matthew T. Walters

We present a quantitative continuum theory of ``flocking'': the collective coherent motion of large numbers of self-propelled organisms. Our model predicts the existence of an ``ordered phase'' of flocks, in which all members of the flock…

Statistical Mechanics · Physics 2009-10-31 John Toner , Yuhai Tu

We consider a simple model of modified gravity interacting with a single scalar field $\varphi$ with weakly coupled exponential potential within the framework of non-Riemannian spacetime volume-form formalism. The specific form of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-03 David Benisty , Eduardo I. Guendelman , Emil Nissimov , Svetlana Pacheva

We consider the inhomogeneous (or density dependent) incompressible Euler equations in a three-dimensional periodic domain. We construct density $\varrho$ and velocity $u$ such that, for any $\alpha<1/7$, both of them are $\alpha $-H\"older…

Analysis of PDEs · Mathematics 2025-11-27 Vikram Giri , Ujjwal Koley