title: Aspects of the density field in an active nematic.
abstract: Active nematics are conceptually the simplest orientationally ordered phase of self-driven particles, but have proved to be a perennial source of surprises. We show here through numerical solution of coarse-grained equations for the order parameter and density that the growth of the active nematic phase from the isotropic phase is necessarily accompanied by a clumping of the density. The growth kinetics of the density domains is shown to be faster than the [Formula: see text] law expected for variables governed by a conservation law. Other results presented include the suppression of density fluctuations in the stationary ordered nematic by the imposition of an orienting field. We close by posing some open questions.
authors.affiliation: Department of Theoretical Sciences, S N Bose National Centre for Basic Sciences, Kolkata 700 098, India.
authors.forename: Shradha
authors.initials: S
authors.lastname: Mishra
authors.affiliation: School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110 067, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Puri
authors.affiliation: TIFR Centre for Interdisciplinary Sciences, Hyderabad 500 075, India sriram@tifrh.res.in.
authors.forename: Sriram
authors.initials: S
authors.lastname: Ramaswamy
keywords: active matter; motility; self-propelled systems