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arXiv · 2209.11161

On G-fractional diffusion models in bounded domains

L. Angelani·R. Garra
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Abstract

In the recent literature, the g-subdiffusion equation involving Caputo fractional derivatives with respect to another function has been studied in relation to anomalous diffusions with a continuous transition between different subdiffusive regimes. In this paper we study the problem of g-fractional diffusion in a bounded domain with absorbing boundaries. We find the explicit solution for the initial-boundary value problem and we study the first passage time distribution and the mean first-passage time (MFPT). An interestin outcome is the proof that with a particular choice of the function $g$ it is possible to obtain a finite MFPT, differently from the anomalous diffusion described by a fractional heat equation involving the classical Caputo derivative.

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BibTeXRIS

L. Angelani, R. Garra. 2022-09-20. On G-fractional diffusion models in bounded domains. https://doi.org/10.1103/physreve.107.014127

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