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arXiv · 1310.6075

Renormalization of the momentum density on the lattice using shifted boundary conditions

Daniel Robaina·Harvey B. Meyer
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Abstract

In order to extract transport quantities from energy-momentum-tensor (EMT) correlators in Lattice QCD there is a strong need for a non-perturbative renormalization of these operators. This is due to the fact that the lattice regularization explicitly breaks translational invariance, invalidating the non-renormalization-theorem. Here we present a non-perturbative calculation of the renormalization constant of the off-diagonal components of the EMT in SU(3) pure gauge theory using lattices with shifted boundary conditions. This allows us to induce a non-zero momentum in the system controlled by the shift parameter and to determine the normalization of the momentum density operator.

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Daniel Robaina, Harvey B. Meyer. 2013-10-22. Renormalization of the momentum density on the lattice using shifted boundary conditions. https://arxiv.org/abs/1310.6075

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