Why Bob beats Alice on X (=Twitter)? Special Lecture by Professor Geoffrey Grimmett, honorary graduand

This general interest talk is suitable for anyone who knows how to flip a coin. A tantalising maths problem involving coin flips goes ‘viral' on X, and the world votes (incorrectly) on the answer. This prompted the speaker to reflect on (a) the right answer, (b) the relevance of social media in doing maths, and (c) the use of AI in maths, though no profound wisdom on (b) and (c) is proposed here. The problem itself, however, has a beautiful solution that illustrates the basic properties of reversal, coupling, and renewal. The only analytical technique used is de Moivre's local central limit theorem from 1733.

Professor Grimmett is a former Head of the Department of Pure Mathematics and Mathematical Statistics at Cambridge and former Director of the Heilbronn Institute for Mathematical Research.

Tea will be served in the Mathematical Institute common room following the talk.