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arXiv · 2202.03970

Renormalization of the $3D$ $SU(N)$ scalar energy-momentum tensor using the Wilson flow

Joseph K. L. Lee·Luigi Del Debbio·Elizabeth Dobson·Andreas Jüttner·Ben Kitching-Morley·Valentin Nourry·Antonin Portelli·Henrique Bergallo Rocha·Kostas Skenderis
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Abstract

In the holographic approach to cosmology, cosmological observables are described in terms of correlators of a three-dimensional boundary quantum field theory. As a concrete model, we study the $3D$ massless $SU(N)$ scalar matrix field theory with a $\phi^4$ interaction. On the lattice, the energy-momentum tensor (EMT) in this theory can mix with the operator $\phi^2$. We utilize the Wilson Flow to renormalize the EMT on the lattice, and present numerical results for the mixing coefficient for $N = 2$. Obtaining the renormalized EMT will allow us to make predictions for the CMB power spectra in the regime where the dual QFT is non-perturbative.

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Joseph K. L. Lee, Luigi Del Debbio, Elizabeth Dobson, Andreas Jüttner, Ben Kitching-Morley, Valentin Nourry, Antonin Portelli, Henrique Bergallo Rocha, Kostas Skenderis. 2022-02-08. Renormalization of the $3D$ $SU(N)$ scalar energy-momentum tensor using the Wilson flow. https://arxiv.org/abs/2202.03970

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