The mass of the eta' in self-dual QCD
Abstract
The QCD gauge field is modeled as an ensemble of statistically independent selfdual and antiselfdual regions. This model is motivated from instanton physics. The scale anomaly then allows to relate the topological susceptibility to the gluon condensate. With the help of Wittens formula for meta' and an estimate of the suppression of the gluon condensate due to light quarks the mass of the eta' can be related to fpi and the physical gluon condensate. We get the quite satisfactory value meta'=884+-116 MeV. Using the physical eta' mass as an input it is in princple possible to get information about the interaction between instantons and anti-instantons.
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.