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Related papers: Fractional spherical random fields

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We consider time-dependent space isotropic and time stationary spherical Gaussian random fields. We establish Chung's law of the iterated logarithm and solve the small probabilities problem. Our results depend on the high-frequency…

Probability · Mathematics 2024-04-11 Marco Carfagnini , Anna Paola Todino

Within the scope of a spherically symmetric space-time we study the role of different types of matter in the formation of different configurations with spherical symmetries. Here we have considered matter with barotropic equation of state,…

General Relativity and Quantum Cosmology · Physics 2021-11-22 Bijan Saha

This paper establishes explicit solutions for fractional diffusion problems on bounded domains. It also gives stochastic solutions, in terms of Markov processes time-changed by an inverse stable subordinator whose index equals the order of…

Probability · Mathematics 2016-04-22 Boris Baeumer , Tomasz Luks , Mark M. Meerschaert

This paper investigates solutions of hyperbolic diffusion equations in $\mathbb{R}^3$ with random initial conditions. The solutions are given as spatial-temporal random fields. Their restrictions to the unit sphere $S^2$ are studied. All…

We develop a technique relating scalar fields with different masses in different conformally flat space-times. We apply this technique to the case of FRW space-times, with $k=\pm 1,0$, and discuss several examples. We also study various…

General Relativity and Quantum Cosmology · Physics 2019-10-08 Swayamsidha Mishra , Sudipta Mukherji , Yogesh K. Srivastava

Spherical field theory is a new non-perturbative method for studying quantum field theories. It uses the spherical partial wave expansion to reduce a general d-dimensional Euclidean field theory into a set of coupled one-dimensional…

High Energy Physics - Theory · Physics 2010-11-19 Dean Lee

This note treats several problems for the fractional perimeter or $s$-perimeter on the sphere. The spherical fractional isoperimetric inequality is established. It turns out that the equality cases are exactly the spherical caps.…

Functional Analysis · Mathematics 2020-12-01 Andreas Kreuml , Olaf Mordhorst

In practice many problems related to space/time fractional equations depend on fractional parameters. But these fractional parameters are not known a priori in modelling problems. Hence continuity of the solutions with respect to these…

Analysis of PDEs · Mathematics 2016-11-14 Duc Trong Dang , Erkan Nane , Dang Minh Nguyen , Nguyen Huy Tuan

The vector system of linear differential equations for a field with arbitrary fractional spin is proposed using infinite-dimensional half-bounded unitary representations of the $\overline{SL(2,R)}$ group. In the case of $(2j+1)$-dimensional…

High Energy Physics - Theory · Physics 2009-10-28 J. L. Cortes , M. S. Plyushchay

We consider the variational structure of a time-fractional second order Mean Field Games (MFG) system with local coupling. The MFG system consists of time-fractional Fokker-Planck and Hamilton-Jacobi-Bellman equations. In such a situation…

Analysis of PDEs · Mathematics 2019-07-03 Tang Qing , Fabio Camilli

The work in this paper is four-fold. Firstly, we introduce an alternative approach to solve fractional ordinary differential equations as an expected value of a random time process. Using the latter, we present an interesting numerical…

Dynamical Systems · Mathematics 2022-12-28 Tamer Oraby , Harrinson Arrubla , Erwin Suazo

Fractional calculus allows one to generalize the linear, one-dimensional, diffusion equation by replacing either the first time derivative or the second space derivative by a derivative of fractional order. The fundamental solutions of…

Statistical Mechanics · Physics 2007-05-23 Francesco Mainardi , Paolo Paradisi , Rudolf Gorenflo

We consider fractional diffusion equations and study the stability of the inverse problem of determining the time-dependent parameter in a source term or a coefficient of zero-th order term from observations of the solution at one point in…

Analysis of PDEs · Mathematics 2015-01-09 Kenichi Fujishiro , Yavar Kian

Cosmological models of a scalar field with dynamical equations containing fractional derivatives or derived from the Einstein-Hilbert action of fractional order, are constructed. A number of exact solutions to those equations of fractional…

General Relativity and Quantum Cosmology · Physics 2011-08-22 V. K. Shchigolev

Abstrct: In this note, by considering fractionally linear functions over a finite field and consequently developing an abstract sequence, we study some of its properties.

Discrete Mathematics · Computer Science 2007-05-23 V. M. Siddlenikov , R. N. Mohan , Moon Ho Lee

We consider the problem of a rotating charged spherical shell of radius a carrying an axially symmetric distribution of charge. We give the interior and exterior solutions to this problem for arbitrary zonal dependence of the surface charge…

Classical Physics · Physics 2010-10-12 Stanislaw Olbert , John W. Belcher

In the paper we study the subject of positivity of systems with sequential fractional difference. We give formulas for the unique solutions of systems in linear and semi-linear cases. The positivity of systems is considered.

Dynamical Systems · Mathematics 2013-04-15 Ewa Girejko , Dorota Mozyrska , Małgorzata Wyrwas

For fractional derivatives and time-fractional differential equations, we construct a framework on the basis of the operator theory in fractional Sobolev spaces. Our framework provides a feasible extension of the classical Caputo and the…

Analysis of PDEs · Mathematics 2022-01-24 Masahiro Yamamoto

The static and time-dependent potential and surface charge correlations in a plasma with a boundary are computed for different shapes of the boundary. The case of a spheroidal or spherical one-component plasma is studied in detail because…

Condensed Matter · Physics 2009-10-28 G. Tellez

While free and weakly interacting particles are well described by a a second-quantized nonlinear Schr\"odinger field, or relativistic versions of it, the fields of strongly interacting particles are governed by effective actions, whose…

Quantum Physics · Physics 2015-06-11 H. Kleinert