1999/03/22 by Gerard 't Hooft, Hooft, Gerard 't
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Theory (hep-th) #hep-th
paper · pdf · doi:10.48550/arxiv.hep-th/9903189
17 pages plain TeX, 1 figure PostScript. Revised paper. A numerical error in previous version needed to be corrected
arxiv created 1999/10/05 · arxiv updated 2009/11/30
When the theory of Quantum Chromodynamics was introduced, it was to explain the observed phenomena of quark confinement and scaling. It was then discovered that the emergence of instantons is an essential consequence of this theory. This led to unanticipated explanations not only for the anomalously high masses of the η and the η' particles, but also for the remarkable differences that had been observed in the mixing angles for the pseudoscalar mesons and the vector mesons.