The Reality of the Fundamental Topological Structure in the QCD Vacuum

TL;DR

This paper provides evidence that the long-range topological structures observed in the QCD vacuum are genuine features of QCD dynamics, not artifacts of measurement, by showing they disappear upon randomizing gauge fields.

Contribution

It demonstrates that the fundamental topological structure in the QCD vacuum is a real consequence of QCD dynamics, confirmed by the disappearance of structure after gauge field randomization.

Findings

Long-range topological structures are present in QCD configurations.

Randomizing gauge fields destroys the observed topological structure.

The structure's existence is linked to the underlying QCD vacuum dynamics.

Abstract

Long-range order of a specific kind has recently been found directly in configurations dominating the regularized QCD path integral. In particular, a low-dimensional global structure was identified in typical space-time distributions of topological charge defined via the overlap Dirac matrix. The presence of the order has been concluded from the fact that the structure disappears after random permutation of position coordinates in measured densities. Here we complete the argument for the reality of this structure (namely the conjecture that its existence is a consequence of QCD dynamics and not an artifact of the overlap-based definition of lattice topological field) by showing that the structure ceases to exist after randomizing the space-time coordinates of the underlying gauge field. This implies that the long-range order present in the overlap-based topological density is indeed a manifestation of QCD vacuum, and that the notion of the fundamental structure (structure involving relevant features at all scales) is viable.