Search results for "Levy noise"

showing 3 items of 3 documents

Effects of Lévy noise on the dynamics of sine-Gordon solitons in long Josephson junctions

2015

We numerically investigate the generation of solitons in current-biased long Josephson junctions in relation to the superconducting lifetime and the voltage drop across the device. The dynamics of the junction is modelled with a sine-Gordon equation driven by an oscillating field and subject to an external non-Gaussian noise. A wide range of $\alpha$-stable L\'evy distributions is considered as noise source, with varying stability index $\alpha$ and asymmetry parameter $\beta$. In junctions longer than a critical length, the mean switching time (MST) from superconductive to the resistive state assumes a values independent of the device length. Here, we demonstrate that such a value is direc…

PhysicsJosephson effectStatistics and ProbabilityCondensed Matter - SuperconductivityDynamics (mechanics)large deviations in non-equilibrium systemsLarge deviations in non-equilibrium systems; mesoscopic systems (theory); metastable states; stochastic processes (theory); Statistics and Probability; Statistical and Nonlinear Physics; Statistics Probability and UncertaintyStatistical and Nonlinear Physicsstochastic processes (theory)metastable state01 natural sciencesSettore FIS/03 - Fisica Della Materia010305 fluids & plasmasLevy noiseQuantum mechanicsLarge deviations in non-equilibrium systemmesoscopic systems (theory)Condensed Matter::Superconductivitymetastable states0103 physical scienceslarge deviations in non-equilibrium systems; mesoscopic systems (theory); metastable states; stochastic processes (theory)SineStatistics Probability and Uncertainty010306 general physicsStatistical and Nonlinear Physic
researchProduct

The problem of analytical calculation of barrier crossing characteristics for Levy flights

2008

By using the backward fractional Fokker-Planck equation we investigate the barrier crossing event in the presence of Levy noise. After shortly review recent results obtained with different approaches on the time characteristics of the barrier crossing, we derive a general differential equation useful to calculate the nonlinear relaxation time. We obtain analytically the nonlinear relaxation time for free Levy flights and a closed expression in quadrature of the same characteristics for cubic potential.

Statistics and ProbabilityPhysicsexact results stochastic particle dynamics (theory)Statistical Mechanics (cond-mat.stat-mech)Differential equationEvent (relativity)Mathematical analysisFOS: Physical sciencesClosed expressionStatistical and Nonlinear PhysicsQuadrature (mathematics)Nonlinear systemLevy noiseExact resultsLévy flightStatistics Probability and UncertaintyCondensed Matter - Statistical Mechanics
researchProduct

Environmental noise and nonlinear relaxation in biological systems

2009

We investigate the role of the environmental noise in three biological systems: (i) an ecosystem described by a Verhulst model with a multiplicative Lévy noise; (ii) polymer translocation, and (ii) individuals of Nezara viridula. Specifically the transient dynamics of the Verhulst model perturbed by arbitrary non-Gaussian white noise is investigated as a first biological system. For Cauchy stable noise, exact results for the probability distribution of the population density and nonlinear relaxation are derived. We find a transition induced by the multiplicative Lévy noise, from a trimodal probability distribution to a bimodal probability distribution in asymptotics, and a nonmonotonic beha…

Levy NoisePolymer translocationBiological systemSettore FIS/01 - Fisica SperimentaleEnvironmental noise
researchProduct