Aachen 2019 – wissenschaftliches Programm
T 46.5: Vortrag
Dienstag, 26. März 2019, 17:00–17:15, ST 8
The gradient flow at higher orders in perturbation theory — Johannes Artz1, Robert V. Harlander1, Yannick Kluth2, •Fabian Lange1, Tobias Neumann3,4, and Mario Prausa5 — 1RWTH Aachen University, Aachen, Germany — 2University of Sussex, Brighton, UK — 3Illinois Institute of Technology, Chicago, USA — 4Fermilab, Batavia, USA — 5Albert-Ludwigs-Universität, Freiburg, Germany
The gradient or Wilson flow has proven to be a useful tool in lattice QCD calculations in the last years. It also offers promising possibilities of cross-fertilization of lattice and perturbative calculations. Up to now, perturbative calculations in the gradient-flow formalism have mostly been carried out to next-to-leading order. Experience shows that the step to next-to-next-to-leading order (NNLO) typically leads to a significant improvement of the perturbative accuracy.
We apply well-known techniques for multi-loop calculations to the gradient-flow formalism in order to systematically compute higher orders. After describing our general setup, we show NNLO results of central observables like the gluon action density, which may offer a possibility to extract αs from lattice results. We also present a lattice formulation of the energy-momentum tensor in the gradient-flow formalism through NNLO.