Dominic Welsh (1938-2023)

TL;DR

This paper is a biographical and scientific memoir of Dominic Welsh, highlighting his key contributions to probability, combinatorics, matroid theory, and computational complexity, and his influence on the scholarly community.

Contribution

It provides a comprehensive overview of Welsh's pioneering work, including the first subadditive ergodic theorem and foundational results in matroid theory and computational complexity.

Findings

Formulated and proved the first subadditive ergodic theorem

Produced the first monograph on matroid theory

Analyzed the complexity of computing the Tutte polynomial

Abstract

This biographical and scientific memoir of Dominic Welsh includes summaries of his important contributions to probability and combinatorics. With John Hammersley, he introduced first-passage percolation, and in so doing they formulated and proved the first subadditive ergodic theorem. Welsh has numerous results in matroid theory, and wrote the first monograph on the topic. He worked on computational complexity and particularly the complexity of computing the Tutte polynomial. He was an inspirational teacher and advisor who helped to develop a community of scholars in combinatorics.