By subtracting from a recent lattice measurement of the thermal vector-current correlator the known 5-loop vacuum contribution, we demonstrate that the remainder is small and shows no visible short-distance divergence. It can therefore in principle be subjected to model-independent analytic continuation. Testing a particular implementation, we obtain estimates for the flavour-diffusion coefficient (2 pi T D \gsim 0.8) and electrical conductivity which are significantly smaller than previous results. Although systematic errors remain beyond control at present, some aspects of our approach could be of a wider applicability.
@article{arxiv.1201.1994,
title = {Towards flavour diffusion coefficient and electrical conductivity without ultraviolet contamination},
author = {Y. Burnier and M. Laine},
journal= {arXiv preprint arXiv:1201.1994},
year = {2015}
}
Comments
7 pages. v2: clarifications added, published version