Eliminativism and the QCD \(\theta_{\mathrm{YM}}\)-term: what gauge transformations cannot do
The nature of the \((F\wedge F)\) term in the Yang-Mills models is investigated. It is argued that while this term (its trace) is fully gauge-invariant (whether the gauge transformation is small or large), and is a total derivative (hence not affecting the equation of motion), its integral is a topological quantity, and hence is physical (observable).
scientific article; zbMATH DE number 7879203
scientific article