2008/05/30 by C. Barrett-Freeman, M. R. Evans, Davide Marenduzzo +3 · 15 citations
Chemistry · Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Chemistry #Classical mechanics #Colloid #Colloidal particle #Earth Systems and Cosmic Evolution #Geology #Materials science #Non-equilibrium thermodynamics #Particle (ecology) #Particle Dynamics in Fluid Flows #Phase (matter) #Phase transition #Physics #Quantum mechanics #Sediment #Sedimentation #Sedimentation equilibrium #Suspension (topology) #Thermodynamics #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevlett.101.100602
published in Physical Review Letters 101(10), 100602 (American Physical Society) · 4 pages, 4 figures
arxiv created 2008/05/30 · openalex publication_date 2008/09/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study numerically and analytically the dynamics of a sedimenting suspension of active, reproducing particles, such as growing bacteria in a gravitational field. In steady state we find a nonequilibrium phase transition between a "sedimentation" regime, analogous to the sedimentation equilibrium of passive colloids, and a "uniform" regime, in which the particle density is constant in all but the top and bottom of the sample. We discuss the importance of fluctuations in particle density in locating the phase-transition point, and report the kinetics of sedimentation at early times.