Speaker
Description
We present our latest results on the Landau-gauge four-gluon vertex, obtained from extensive lattice QCD simulations. By exploiting the planar degeneracy property previously observed for the three-gluon vertex, and assuming it as an approximation for the four-gluon case, we are able to go beyond the previously exploited collinear kinematics and extract lattice results in more general configurations, calculating the first clear signal of its tree-level form factor.
Our analysis relies on a large set of kinematical configurations, which are classified in terms of a single invariant defined as a symmetric combination of the squared external momenta. This classification significantly improves the statistical precision of our results. As a direct application, we perform the first lattice determination of the running coupling associated with the four-gluon vertex.