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arXiv · 1612.07721

Renormalisation of the scalar energy-momentum tensor with the Wilson flow

Francesco Capponi·Luigi Del Debbio·Susanne Ehret·Roberto Pellegrini·Antonin Portelli·Antonio Rago
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Abstract

The non-perturbative computation of the energy-momentum tensor can be used to study the scaling behaviour of strongly coupled quantum field theories. The Wilson flow is an essential tool to find a meaningful formulation of the energy-momentum tensor on the lattice. We extend recent studies of the renormalisation of the energy-momentum tensor in four-dimensional gauge theory to the case of a three-dimensional scalar theory to investigate its intrinsic structure and numerical feasibility on a more basic level. In this paper, we discuss translation Ward identities, introduce the Wilson flow for scalar theory, and present our results for the renormalisation constants of the scalar energy-momentum tensor.

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Francesco Capponi, Luigi Del Debbio, Susanne Ehret, Roberto Pellegrini, Antonin Portelli, Antonio Rago. 2016-12-22. Renormalisation of the scalar energy-momentum tensor with the Wilson flow. https://arxiv.org/abs/1612.07721

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