algebraic quantum field theory (perturbative, on curved spacetimes, homotopical)
quantum mechanical system, quantum probability
interacting field quantization
In Yang-Mills theory on 4d Minkowski spacetime the theta vacuum is a vacuum state which is a superposition of each Yang-Mills instanton-sector weighted by a complex phase proportional to the theta angle times the instanton number.
Survey is in
Detailed argument for the theta vacuum from chiral symmetry breaking is offered in
Curtis Callan, R.F. Dashen, David Gross, The Structure of the Gauge Theory Vacuum, Phys.Lett. 63B (1976) 334-340 (spire)
G. Morchio, Franco Strocchi, Chiral symmetry breaking and theta vacuum structure in QCD, Annals Phys.324:2236-2254, 2009 (arXiv:0907.2522)
Last revised on May 17, 2019 at 16:08:24. See the history of this page for a list of all contributions to it.