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arXiv · 2604.10204

William A. Bardeen -- A Brief Biography

Christopher T. Hill
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Abstract

William Allan Bardeen (September 15, 1941 $-$ November 18, 2025) was an American theoretical physicist who worked at the Fermi National Accelerator Laboratory. He is renowned for his foundational work on the chiral anomaly, the Adler-Bardeen theorem, the non-Abelian anomaly and gravitational anomalies. He was instrumental in the development of quantum chromodynamics and its applications, such as semileptonic decays and the $\Lambda_{\overline{MS}}$ scheme frequently used in perturbative analysis of high energy processes involving strong interactions. Bardeen also played a major role in developing a theory of dynamical breaking of electroweak symmetry via top quark condensates, leading to one of the first composite Brout-Englert-Higgs boson models. His work on the chiral symmetry dynamics of heavy-light quark bound states correctly predicted abnormally long-lived resonances which are chiral symmetry partners of the ground state.

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Christopher T. Hill. 2026-04-11. William A. Bardeen -- A Brief Biography. https://arxiv.org/abs/2604.10204

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