Periodic Theta Vacuum Model and the QCD Instanton Vacuum
Abstract
We formulate a toy model for the θ vacuum that embodies the n-point moments of the even and odd topological charge densities. The partition function is 2π periodic only after resumming over all winding modes. We apply the same analysis to the quenched instanton vacuum at finite θ and derive saddle-point results for the vacuum energy density that are manifestly 2π periodic whatever θ. We briefly discuss the consequences of unquenching the fermions on our results.
0
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.