Vorträge in der Woche 19.10.2026 bis 25.10.2026

Donnerstag, 22.10.2026: Algorithmic Randomness and Physical Typicality

Prof. Eddy Keming Chen (University of California, San Diego)

Appeals to typicality are common in physics, but it is often unclear what it means for a physical state to be typical relative to a probability measure, and correspondingly unclear what a law that appeals to typicality asserts. Here we consider how one might characterize physical typicality using ideas from the theory of algorithmic randomness. As a concrete example, we show how taking a physical state to be typical relative to a computable measure when it is Martin-Löf random allows one to formulate the distribution postulate in Bohmian mechanics as a statistical constraining law of the theory. Using a toy model, we show how this constraint guarantees the standard Born statistics for computable experimental protocols. Algorithmic Bohmian mechanics (aBM) thus illustrates how algorithmic randomness may be used to provide precise content to a statistical law. (Joint work with Jeffrey A. Barrett and Josiah Lopez-Wild; paper forthcoming in /Philosophy of Science,/ preprint at https://arxiv.org/abs/2609.06268) Two other related papers: Algorithmic Randomness and Probabilistic Laws (with Jeffrey A. Barrett) /The British Journal for the Philosophy of Science/, forthcoming, https://arxiv.org/abs/2303.01411 Algorithmic Randomness, Exchangeability, and the Principal Principle (with Jeffrey A. Barrett) /The British Journal for the Philosophy of Science/, forthcoming, https://arxiv.org/abs/2510.24054