Active nematics on a substrate: Giant number fluctuations and long-time tails

2002/08/29 by Sriram Ramaswamy, Sriraṁ Ramaswamy, Robert Simha +2 · 20 citations
Computer Science · Engineering · Physics and Astronomy · #Characterization and Applications of Magnetic Nanoparticles #Geology #Micro and Nano Robotics #Nonlinear Dynamics and Pattern Formation #Physics #Statistical physics #Substrate (aquarium) #cond-mat.soft #cond-mat.stat-mech

paper · pdf · doi:10.1209/epl/i2003-00346-7

Submitted to Europhys Lett 26 Aug 2002

arxiv created 2002/08/29 · openalex publication_date 2003/04/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We construct the equations of motion for the coupled dynamics of order parameter and concentration for the nematic phase of driven particles on a solid surface, and show that they imply i) giant number fluctuations, with a standard deviation proportional to the mean in dimension d = 2 of primary relevance to experiment, and ii) long-time tails ∼ t − d /2 in the autocorrelation of the particle velocities despite the absence of a hydrodynamic velocity field. Our predictions can be tested in experiments on aggregates of amoeboid cells as well as on layers of agitated granular matter.

Citations

• Particles Sliding on a Fluctuating Surface: Phase Separation and Power Laws
• The Physics of Liquid Crystals
• Hydrodynamic Fluctuations and Instabilities in Ordered Suspensions of Self-Propelled Particles
• Unified Hydrodynamic Theory for Crystals, Liquid Crystals, and Normal Fluids

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