Continuous time random walk, Mittag-Leffler waiting time and fractional diffusion: mathematical aspects

We show the asymptotic long-time equivalence of a generic power law waiting time distribution to the Mittag-Leffler waiting time distribution, characteristic for a time fractional CTRW. This asymptotic equivalence is effected by a combination of "rescaling" time and "respeeding" the relevant renewal process followed by a passage to a limit for which we need a suitable relation between the parameters of rescaling and respeeding. Turning our attention to spatially 1-D CTRWs with a generic power law jump distribution, "rescaling" space can be interpreted as a second kind of "respeeding" which then, again under a proper relation between the relevant parameters leads in the limit to the space-time fractional diffusion equation. Finally, we treat the `time fractional drift" process as a properly scaled limit of the counting number of a Mittag-Leffler renewal process.

[1]  R. Gorenflo,et al.  Fractional Calculus: Integral and Differential Equations of Fractional Order , 2008, 0805.3823.

[2]  Rudolf Gorenflo,et al.  From Power Laws to Fractional Diffusion: the Direct Way , 2007, 0801.0142.

[3]  Marcin Kotulski,et al.  Asymptotic distributions of continuous-time random walks: A probabilistic approach , 1995 .

[4]  Hans-Peter Scheffler,et al.  Stochastic solution of space-time fractional diffusion equations. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[5]  Francesco Mainardi,et al.  Continuous-time random walk and parametric subordination in fractional diffusion , 2007 .

[6]  F. Mainardi,et al.  The fundamental solution of the space-time fractional diffusion equation , 2007, cond-mat/0702419.

[7]  Sheldon M. Ross,et al.  Introduction to Probability Models (4th ed.). , 1990 .

[8]  Enrico Scalas,et al.  The application of continuous-time random walks in finance and economics , 2006 .

[9]  R. Gorenflo,et al.  Fractional calculus and continuous-time finance , 2000, cond-mat/0001120.

[10]  R. Gorenflo,et al.  A fractional generalization of the Poisson processes , 2007, math/0701454.

[11]  V. Balakrishnan,et al.  Anomalous diffusion in one dimension , 1985 .

[12]  M. Caputo Linear Models of Dissipation whose Q is almost Frequency Independent-II , 1967 .

[13]  Svetlozar T. Rachev,et al.  Univariate Geometric Stable Laws , 1999 .

[14]  곽순섭,et al.  Generalized Functions , 2006, Theoretical and Mathematical Physics.

[15]  Sheldon M. Ross,et al.  Introduction to probability models , 1975 .

[16]  Enrico Scalas,et al.  Uncoupled continuous-time random walks: Solution and limiting behavior of the master equation. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[17]  Wojbor A. Woyczyński,et al.  Models of anomalous diffusion: the subdiffusive case , 2005 .

[18]  E. C. Titchmarsh,et al.  The Laplace Transform , 1991, Heat Transfer 1.

[19]  T. Huillet Renewal processes and the Hurst effect , 2002 .

[20]  R. N. Pillai On Mittag-Leffler functions and related distributions , 1990 .

[21]  A. Erdélyi,et al.  Higher Transcendental Functions , 1954 .

[22]  E. Montroll,et al.  Random Walks on Lattices. II , 1965 .

[23]  Rudolf Hilfer,et al.  EXACT SOLUTIONS FOR A CLASS OF FRACTAL TIME RANDOM WALKS , 1995 .

[24]  Hilfer,et al.  Fractional master equations and fractal time random walks. , 1995, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[25]  Francesco Mainardi,et al.  Fractional Calculus: Some Basic Problems in Continuum and Statistical Mechanics , 2012, 1201.0863.

[26]  Alexander I. Saichev,et al.  Fractional kinetic equations: solutions and applications. , 1997, Chaos.

[27]  Francesco Mainardi,et al.  Fractional Diffusion Processes: Probability Distributions and Continuous Time Random Walk , 2007, 0709.3990.

[28]  Feller William,et al.  An Introduction To Probability Theory And Its Applications , 1950 .

[29]  E. Montroll Random walks on lattices , 1969 .

[30]  Francesco Mainardi,et al.  The Wright functions as solutions of the time-fractional diffusion equation , 2003, Appl. Math. Comput..

[31]  Francesco Mainardi,et al.  On Mittag-Leffler-type functions in fractional evolution processes , 2000 .

[32]  O. Marichev,et al.  Fractional Integrals and Derivatives: Theory and Applications , 1993 .

[33]  T. MacRobert Higher Transcendental Functions , 1955, Nature.

[34]  R. Gorenflo,et al.  Analytical properties and applications of the Wright function , 2007, math-ph/0701069.

[35]  M. Caputo Linear models of dissipation whose Q is almost frequency independent , 1966 .

[36]  W. Schneider,et al.  Fractional diffusion and wave equations , 1989 .

[37]  R. Gorenflo,et al.  Wright functions as scale-invariant solutions of the diffusion-wave equation , 2000 .

[38]  T. Huillet ON THE WAITING TIME PARADOX AND RELATED TOPICS , 2002 .

[39]  Francesco Mainardi,et al.  Simply and multiply scaled diffusion limits for continuous time random walks , 2005 .

[40]  J. Klafter,et al.  Anomalous Diffusion and Relaxation Close to Thermal Equilibrium: A Fractional Fokker-Planck Equation Approach , 1999 .

[41]  S. D. Eidelman,et al.  Cauchy problem for evolution equations of a fractional order , 2004 .

[42]  F. Mainardi Fractional Relaxation-Oscillation and Fractional Diffusion-Wave Phenomena , 1996 .

[43]  E. Montroll,et al.  CHAPTER 2 – On an Enriched Collection of Stochastic Processes* , 1979 .

[44]  Francesco Mainardi,et al.  Linear models of dissipation in anelastic solids , 1971 .

[45]  K. Weron,et al.  On the Cole-Cole relaxation function and related Mittag-Leffler distribution , 1996 .

[46]  William Feller,et al.  An Introduction to Probability Theory and Its Applications , 1967 .

[47]  CONTINUOUS TIME RANDOM WALK AND TIME FRACTIONAL DIFFUSION: A NUMERICAL COMPARISON BETWEEN THE FUNDAMENTAL SOLUTIONS , 2005 .

[48]  R. Silbey,et al.  Fractional Kramers Equation , 2000 .

[49]  Rudolf Hilfer,et al.  On fractional diffusion and continuous time random walks , 2003 .

[50]  Elliott W. Montroll,et al.  Random walks on lattices. IV. Continuous-time walks and influence of absorbing boundaries , 1973 .

[51]  V. Kiryakova Generalized Fractional Calculus and Applications , 1993 .

[52]  Francesco Mainardi,et al.  Renewal processes of Mittag-Leffler and Wright type , 2005 .

[53]  R. Gorenflo,et al.  Fractional calculus and continuous-time finance II: the waiting-time distribution , 2000, cond-mat/0006454.

[54]  Do strange kinetics imply unusual thermodynamics? , 2000, Physical review. E, Statistical, nonlinear, and soft matter physics.

[55]  On Hilfer's objection to the fractional time diffusion equation , 2007 .

[56]  B. Gnedenko,et al.  Limit Distributions for Sums of Independent Random Variables , 1955 .

[57]  Francesco Mainardi,et al.  Discrete and Continuous Random Walk Models for Space-Time Fractional Diffusion , 2004 .

[58]  Enrico Scalas,et al.  Fractional Calculus and Continuous-Time Finance III : the Diffusion Limit , 2001 .