title: Expanding scroll rings and negative tension turbulence in a model of excitable media.
abstract: Scroll waves in excitable media, described by the Barkley model, are studied. In the parameter region of weak excitability, negative tension of wave filaments is found. It leads to expansion of scroll rings and instability of wave filaments. A circular filament tends to stretch, bend, loop, and produce an expanding tangle that fills up the volume. The filament does not undergo fragmentation before it touches the boundaries. Statistical properties of such Winfree turbulence of scroll waves are numerically investigated.
authors.affiliation: Departament de Química Física, Universitat de Barcelona, Av. Diagonal 647, 08028 Barcelona, Spain. s.alonso@qf.ub.es
authors.forename: S
authors.initials: S
authors.lastname: Alonso
authors.forename: Ralf
authors.initials: R
authors.lastname: Kähler
authors.forename: A S
authors.initials: AS
authors.lastname: Mikhailov
authors.forename: F
authors.initials: F
authors.lastname: Sagués
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D008955:Models, Cardiovascular; D032342:Muscle Cells / Q000502:physiology*; D009200:Myocardial Contraction / Q000502:physiology*; D017711:Nonlinear Dynamics; D013314:Stress, Mechanical