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Related papers: L\'evy processes on a generalized fractal comb

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Conditional independence and graphical models are crucial concepts for sparsity and statistical modeling in higher dimensions. For L\'evy processes, a widely applied class of stochastic processes, these notions have not been studied. By the…

Statistics Theory · Mathematics 2024-11-13 Sebastian Engelke , Jevgenijs Ivanovs , Jakob D. Thøstesen

In this work, we investigate the fine regularity of L\'evy processes using the 2-microlocal formalism. This framework allows us to refine the multifractal spectrum determined by Jaffard and, in addition, study the oscillating singularities…

Probability · Mathematics 2014-02-11 Paul Balança

We investigate the first-passage dynamics of symmetric and asymmetric L\'evy flights in a semi-infinite and bounded intervals. By solving the space-fractional diffusion equation, we analyse the fractional-order moments of the first-passage…

Statistical Mechanics · Physics 2020-08-26 Amin Padash , Aleksei V. Chechkin , Bartłomiej Dybiec , Marcin Magdziarz , Babak Shokri , Ralf Metzler

Continuous-time random walks combining diffusive scattering and ballistic propagation on lattices model a class of L\'evy walks. The assumption that transitions in the scattering phase occur with exponentially-distributed waiting times…

Statistical Mechanics · Physics 2015-06-11 Giampaolo Cristadoro , Thomas Gilbert , Marco Lenci , David P. Sanders

Memory effects, sometimes, can not be neglected. In the framework of continuous time random walk, memory effect is modeled by the correlated waiting times. In this paper, we derive the two-point probability distribution of the stochastic…

Statistical Mechanics · Physics 2019-01-23 Yao Chen , Xudong Wang , Weihua Deng

In this paper we study processes which are constructed by a convolution of a deterministic kernel with a martingale. A special emphasis is put on the case where the driving martingale is a centred L\'evy process, which covers the popular…

Probability · Mathematics 2021-05-31 Christian Bender , Robert Knobloch , Philip Oberacker

We analyze time-discrete and continuous `fractional' random walks on undirected regular networks with special focus on cubic periodic lattices in $n=1,2,3,..$ dimensions. The fractional random walk dynamics is governed by a master equation…

Recently, anomalous superdiffusion of ultra cold 87Rb atoms in an optical lattice has been observed along with a fat-tailed, L\'evy type, spatial distribution. The anomalous exponents were found to depend on the depth of the optical…

Statistical Mechanics · Physics 2013-05-06 David A. Kessler , Eli Barkai

To model subsurface flow in uncertain heterogeneous\ fractured media an elliptic equation with a discontinuous stochastic diffusion coefficient - also called random field - may be used. In case of a one-dimensional parameter space, L\'evy…

Numerical Analysis · Mathematics 2022-08-26 Andrea Barth , Robin Merkle

Subdiffusion on graphs is often modeled by time-fractional diffusion equations, yet its structural and dynamical consequences remain unclear. We show that subdiffusive transport on graphs is a memory-driven process generated by a random…

Social and Information Networks · Computer Science 2026-01-22 Nikita Deniskin , Ernesto Estrada

An exact analytical analysis of anomalous diffusion on a fractal mesh is presented. The fractal mesh structure is a direct product of two fractal sets which belong to a main branch of backbones and side branch of fingers. The fractal sets…

Statistical Mechanics · Physics 2017-05-10 Trifce Sandev , Alexander Iomin , Holger Kantz

Properties of random and fluctuating systems are often studied through the use of Gaussian distributions. However, in a number of situations, rare events have drastic consequences, which can not be explained by Gaussian statistics.…

Atomic Physics · Physics 2015-05-13 Nicolas Mercadier , William Guerin , Martine Chevrollier , Robin Kaiser

The stochastic motion in a nonhomogeneous medium with traps is studied and diffusion properties of that system are discussed. The particle is subjected to a stochastic stimulation obeying a general L\'evy stable statistics and experiences…

Statistical Mechanics · Physics 2015-06-11 Tomasz Srokowski

Truncated Levy flights are stochastic processes which display a crossover from a heavy-tailed Levy behavior to a faster decaying probability distribution function (pdf). Putting less weight on long flights overcomes the divergence of the…

Condensed Matter · Physics 2009-11-10 I. M. Sokolov , A. V. Chechkin , J. Klafter

The propagation of light that undergoes multiple-scattering by resonant atomic vapor can be described as a L\'evy flight. L\'evy flight is a random walk with heavy tailed step-size (r) distribution, decaying asymptotically as $P(r)\sim…

We formulate the problem of confined L\'evy flight on a comb. The comb represents a sawtooth-like potential field $V(x)$, with the asymmetric teeth favoring net transport in a preferred direction. The shape effect is modeled as a power-law…

Statistical Mechanics · Physics 2018-08-15 Alexander V. Milovanov , Jens Juul Rasmussen

There is an abundance of useful fluctuation identities for one-sided L\'evy processes observed up to an independent exponentially distributed time horizon. We show that all the fundamental formulas generalize to time horizons having matrix…

Probability · Mathematics 2021-01-21 Mogens Bladt , Jevgenijs Ivanovs

We study boundary traces of shift-invariant diffusions: two-dimensional diffusions in the upper half-plane $\mathbb{R} \times [0, \infty)$ (or in $\mathbb{R} \times [0, R)$) invariant under horizontal translations. We prove that the…

Probability · Mathematics 2019-12-03 Mateusz Kwaśnicki

L\'evy flights and L\'evy walks serve as two paradigms of random walks resembling common features but also bearing fundamental differences. One of the main dissimilarities are discontinuity versus continuity of their trajectories and…

Statistical Mechanics · Physics 2017-05-09 Bartlomiej Dybiec , Ewa Gudowska-Nowak , Eli Barkai , Alexander A. Dubkov

We consider correlated L\'evy walks on a class of two- and three-dimensional deterministic self-similar structures, with correlation between steps induced by the geometrical distribution of regions, featuring different diffusion properties.…

Statistical Mechanics · Physics 2015-03-19 Pierfrancesco Buonsante , Raffaella Burioni , Alessandro Vezzani