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Related papers: Diffusive persistence and the `sign-time' distribu…

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Score-based diffusion models have recently emerged as state-of-the-art generative models for a variety of data modalities. Nonetheless, it remains unclear how to adapt these models to generate long multivariate time series. Viewing a time…

Machine Learning · Computer Science 2025-02-28 Barbora Barancikova , Zhuoyue Huang , Cristopher Salvi

We study lower and upper bounds for the probability that a diffusion process in $\mathbb{R}^n$ remains in a tube around a skeleton path up to a fixed time. We assume that the diffusion coefficients $\sigma_1,\ldots,\sigma_d$ may degenerate…

Probability · Mathematics 2016-07-19 Vlad Bally , Lucia Caramellino , Paolo Pigato

Freeze out of particles across three dimensional space-time hypersurface is discussed in a simple kinetic model. The final momentum distribution of emitted particles, for freeze out surfaces with space-like normal, shows a non-exponential…

Nuclear Theory · Physics 2009-10-31 V. K. Magas , Cs. Anderlik , L. P. Csernai , F. Grassi , W. Greiner , Y. Hama , T. Kodama , Zs. Lázár , H. Stöcker

The molecular motion in heterogeneous media displays anomalous diffusion by the mean-squared displacement $\langle X^2(t) \rangle = 2 D t^\alpha$. Motivated by experiments reporting populations of the anomalous diffusion parameters $\alpha$…

Biological Physics · Physics 2025-10-09 Yann Lanoiselée , Gianni Pagnini , Agnieszka Wyłomańska

We present and analyze a space-time Petrov-Galerkin finite element method for a time-fractional diffusion equation involving a Riemann-Liouville fractional derivative of order $\alpha\in(0,1)$ in time and zero initial data. We derive a…

Numerical Analysis · Mathematics 2017-07-26 Beiping Duan , Bangti Jin , Raytcho Lazarov , Joseph Pasciak , Zhi Zhou

Scale-free surfaces, such as cones, remain unchanged under a simultaneous expansion of all coordinates by the same factor. Probability density of a particle diffusing near such absorbing surface at large time approaches a simple form that…

Statistical Mechanics · Physics 2015-04-28 Nir Alfasi , Yacov Kantor

An isotropic passive scalar field $T$ advected by a rapidly-varying velocity field is studied. The tail of the probability distribution $P(\theta,r)$ for the difference $\theta$ in $T$ across an inertial-range distance $r$ is found to be…

chao-dyn · Physics 2009-10-28 Robert H. Kraichnan

The dynamics of a freely diffusing particle in a two-dimensional channel with cross sectional area $A(x)$, can be effectively described by a one-dimensional diffusion equation under the action of a potential of mean force $U(x)=-k_BT\ln…

Statistical Mechanics · Physics 2019-02-28 Matan Sivan , Oded Farago

We study the influence on diffusion in one dimension of a potential energy perturbation varying as a power in space and time. We concentrate on the case of a parabolic perturbation in space decaying as $t^{-\omega}$ which shows a rich…

Statistical Mechanics · Physics 2010-12-08 Loic Turban

We study the diffusion process in the presence of stochastic resetting inside a two-dimensional wedge of top angle $\alpha$, bounded by two infinite absorbing edges. In the absence of resetting, the second moment of the first-passage time…

Statistical Mechanics · Physics 2025-12-01 Fazil Najeeb , Arnab Pal , V. V. Prasad

In this paper, we introduce the persistence transformation, a novel methodology in Topological Data Analysis (TDA) for applications in time series data which can be obtained in various areas such as science, politics, economy, healthcare,…

Algebraic Topology · Mathematics 2024-01-31 Gideon Klaila , Anastasios Stefanou , Lena Ranke

Score-based methods have recently seen increasing popularity in modeling and generation. Methods have been constructed to perform hypothesis testing and change-point detection with score functions, but these methods are in general not as…

Machine Learning · Statistics 2025-06-23 Sean Moushegian , Taposh Banerjee , Vahid Tarokh

We apply the recently introduced distribution of sign-times (DST) to non-equilibrium interface growth dynamics. We are able to treat within a unified picture the persistence properties of a large class of relaxational and noisy linear…

Statistical Mechanics · Physics 2009-10-31 Z. Toroczkai , T. J. Newman , S. Das Sarma

Diffusion with stochastic resetting, instantaneous returns of a diffusing particle to a reference point, creates a stationary probability distribution. The paradigm is extended here to a doubly stochastic protocol in which the resetting…

Statistical Mechanics · Physics 2025-10-01 Maxence Arutkin , Shlomi Reuveni

In this paper we deal with a reaction-diffusion equation in a bounded interval of the real line with a nonlinear diffusion of Perona-Malik's type and a balanced bistable reaction term. Under very general assumptions, we study the…

Analysis of PDEs · Mathematics 2024-05-21 Alessandra De Luca , Raffaele Folino , Marta Strani

We propose a model of sub-diffusion in which an external force is acting on a particle at all times not only at the moment of jump. The implication of this assumption is the dependence of the random trapping time on the force with the…

Statistical Mechanics · Physics 2015-04-16 Sergei Fedotov , Nickolay Korabel

We study nonlinear stability of spatially homogeneous oscillations in reaction-diffusion systems. Assuming absence of unstable linear modes and linear diffusive behavior for the neutral phase, we prove that spatially localized perturbations…

Analysis of PDEs · Mathematics 2008-07-01 Thierry Gallay , Arnd Scheel

We present an analytical study of the time dependent diffusion coefficient in a dilute suspension of spheres with partially absorbing boundary condition. Following Kirkpatrick (J. Chem. Phys. 76, 4255) we obtain a perturbative expansion for…

Statistical Mechanics · Physics 2012-10-29 Jiang Qian , Pabitra N. Sen

We study the Langevin dynamics of a dipole diffusing in a random electrical field E derived from a quenched Gaussian potential. We show that in a suitable adiabatic limit (where the dynamics of the dipole moment is much faster than the…

Disordered Systems and Neural Networks · Physics 2015-05-13 Clement Touya , David S. Dean , Clement Sire

In this paper we prove the local and global well-posedness of the time fractional abstract Schr\"odinger type evolution equation on the Hilbert space and as an application, we prove the local and global well-posedness of the fractional…

Analysis of PDEs · Mathematics 2023-11-29 Mingxuan He , Na Deng