297 research outputs found

    Fokker-Planck Equation with Fractional Coordinate Derivatives

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    Using the generalized Kolmogorov-Feller equation with long-range interaction, we obtain kinetic equations with fractional derivatives with respect to coordinates. The method of successive approximations with the averaging with respect to fast variable is used. The main assumption is that the correlator of probability densities of particles to make a step has a power-law dependence. As a result, we obtain Fokker-Planck equation with fractional coordinate derivative of order 1<α<21<\alpha<2.Comment: LaTeX, 16 page

    Lagrangian formulation of classical fields within Riemann-Liouville fractional derivatives

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    The classical fields with fractional derivatives are investigated by using the fractional Lagrangian formulation.The fractional Euler-Lagrange equations were obtained and two examples were studied.Comment: 9 page

    Constant Curvature Coefficients and Exact Solutions in Fractional Gravity and Geometric Mechanics

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    We study fractional configurations in gravity theories and Lagrange mechanics. The approach is based on Caputo fractional derivative which gives zero for actions on constants. We elaborate fractional geometric models of physical interactions and we formulate a method of nonholonomic deformations to other types of fractional derivatives. The main result of this paper consists in a proof that for corresponding classes of nonholonomic distributions a large class of physical theories are modelled as nonholonomic manifolds with constant matrix curvature. This allows us to encode the fractional dynamics of interactions and constraints into the geometry of curve flows and solitonic hierarchies.Comment: latex2e, 11pt, 27 pages, the variant accepted to CEJP; added and up-dated reference

    A Pseudospectral Algorithm for Solving Multipantograph Delay Systems on a Semi-Infinite Interval Using Legendre Rational Functions

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    A new Legendre rational pseudospectral scheme is proposed and developed for solving numerically systems of linear and nonlinear multipantograph equations on a semi-infinite interval. A Legendre rational collocation method based on Legendre rational-Gauss quadrature points is utilized to reduce the solution of such systems to systems of linear and nonlinear algebraic equations. In addition, accurate approximations are achieved by selecting few Legendre rational-Gauss collocation points. The numerical results obtained by this method have been compared with various exact solutions in order to demonstrate the accuracy and efficiency of the proposed method. Indeed, for relatively limited nodes used, the absolute error in our numerical solutions is sufficiently small

    Time-Fractional KdV Equation: Formulation and Solution using Variational Methods

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    In this work, the semi-inverse method has been used to derive the Lagrangian of the Korteweg-de Vries (KdV) equation. Then, the time operator of the Lagrangian of the KdV equation has been transformed into fractional domain in terms of the left-Riemann-Liouville fractional differential operator. The variational of the functional of this Lagrangian leads neatly to Euler-Lagrange equation. Via Agrawal's method, one can easily derive the time-fractional KdV equation from this Euler-Lagrange equation. Remarkably, the time-fractional term in the resulting KdV equation is obtained in Riesz fractional derivative in a direct manner. As a second step, the derived time-fractional KdV equation is solved using He's variational-iteration method. The calculations are carried out using initial condition depends on the nonlinear and dispersion coefficients of the KdV equation. We remark that more pronounced effects and deeper insight into the formation and properties of the resulting solitary wave by additionally considering the fractional order derivative beside the nonlinearity and dispersion terms.Comment: The paper has been rewritten, 12 pages, 3 figure

    The Fractionary Schr\"{o}dinger Equation, Green Functions and Ultradistributions

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    In this work, we generalize previous results about the Fractionary Schr\"{o}dinger Equation within the formalism of the theory of Tempered Ultradistributions. Several examples of the use of this theory are given. In particular we evaluate the Green's function for a free particle in the general case, for an arbitrary order of the derivative index.Comment: 32 pages. No figure

    Hamilton-Jacobi formalism for Linearized Gravity

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    In this work we study the theory of linearized gravity via the Hamilton-Jacobi formalism. We make a brief review of this theory and its Lagrangian description, as well as a review of the Hamilton-Jacobi approach for singular systems. Then we apply this formalism to analyze the constraint structure of the linearized gravity in instant and front-form dynamics.Comment: To be published in Classical and Quantum Gravit

    Characterization of a benzoic acid modified glassy carbon electrode expressed quantitatively by new statistical parameters

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    The main aim of this study is to characterize the nanosurface of the benzoic acid modified glassy carbon (GC) electrode by using a new statistical approach. In this study, the electrode surfaces were modified by cyclic voltametry in the potential range of +0.4 and -0.8 V at a scan rate 200 mV s-1 for four cycles versus Ag/Ag+ electrode in acetonitrile containing 0.1 M tetrabutylammonium tetraflouroborate (TBATFB). FT-IR spectra of the surface modifier molecules in both solid (GC and nanofilm (GC-benzoic acid)) forms were recorded in the spectral range 600-4000 cm-1. The FT-IR spectra of p-aminobenzoic acid were obtained by using KBr pellets. The above FT-IR spectra of both GC and its nanofilm with benzoic acid were processed by new statistical approach to reach optimal smoothing trend for the characterization of the modified electrode surface consisting of the nanofilm of GC-benzoic acid. In the frame of new statistical approach all measured spectra have been 'read' in terms of a set of universal statistical parameters. © 2008 Elsevier B.V. All rights reserved
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