Distribution of stress tensor around static quark-anti-quark from Yang-Mills gradient flow

The spatial distribution of the stress tensor around the quark-anti-quark (Q (Q) over bar) pair in SU(3) lattice gauge theory is studied. The Yang-Mills gradient flow plays a crucial role to make the stress tensor well-defined and derivable from the numerical simulations on the lattice. The resultant stress tensor with a decomposition into local principal axes shows, for the first time, the detailed structure of the flux tube along the longitudinal and transverse directions in a gauge invariant manner. The linear confining behavior of the Q (Q) over bar potential at long distances is derived directly from the integral of the local stress tensor. (C) 2018 The Authors. Published by Elsevier B.V.