Department of Physics & Astronomy
University of New Mexico

Physics and Astronomy Colloquium

First-Passage Processes in Physics, Biology, and Beyond

Presented by Prof. Sid Redner (Santa Fe Institute)

A fundamental aspect of a random walk is: when does it reach a specified threshold position for the first time? This first-passage time, and more generally, the distribution of first passage times underlies many non-equilibrium phenomena, such as the triggering of integrate and fire neurons, the statistics of cell division, and the execution of stock options. The computation of the first-passage time and its distribution is both simple and beautiful, with profound connections to electrostatic potential theory. I will present some aspects of these fundamentals and then discuss two applications of first-passage ideas: the classic problem of cell reception and a toy model of wealth sharing.

3:30 pm, Friday, September 22, 2023


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