Kinetics of First Passage in a Cone

E. Ben-Naim; P. L. Krapivsky

doi:10.1088/1751-8113/43/49/495007

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arXiv · 1009.0238

Kinetics of First Passage in a Cone

E. Ben-Naim·P. L. Krapivsky

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Abstract

We study statistics of first passage inside a cone in arbitrary spatial dimension. The probability that a diffusing particle avoids the cone boundary decays algebraically with time. The decay exponent depends on two variables: the opening angle of the cone and the spatial dimension. In four dimensions, we find an explicit expression for the exponent, and in general, we obtain it as a root of a transcendental equation involving associated Legendre functions. At large dimensions, the decay exponent depends on a single scaling variable, while roots of the parabolic cylinder function specify the scaling function. Consequently, the exponent is of order one only if the cone surface is very close to a plane. We also perform asymptotic analysis for extremely thin and extremely wide cones.

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BibTeX RIS

E. Ben-Naim, P. L. Krapivsky. 2010-09-01. Kinetics of First Passage in a Cone. https://doi.org/10.1088/1751-8113/43/49/495007

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