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arXiv · 0705.0501

Survival of a diffusing particle in an expanding cage

Alan J Bray·Richard Smith
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Abstract

We consider a Brownian particle, with diffusion constant D, moving inside an expanding d-dimensional sphere whose surface is an absorbing boundary for the particle. The sphere has initial radius L_0 and expands at a constant rate c. We calculate the joint probability density, p(r,t|r_0), that the particle survives until time t, and is at a distance r from the centre of the sphere, given that it started at a distance r_0 from the centre.

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Alan J Bray, Richard Smith. 2007-05-03. Survival of a diffusing particle in an expanding cage. https://doi.org/10.1088/1751-8113/40/36/002

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