On high-order perturbative calculations at finite density
Abstract
We discuss the prospects of performing high-order perturbative calculations in systems characterized by a vanishing temperature but finite density. In particular, we show that the determination of generic Feynman integrals containing fermionic chemical potentials can be reduced to the evaluation of three-dimensional phase space integrals over vacuum on-shell amplitudes - a result reminiscent of a previously proposed "naive real-time formalism" for vacuum diagrams. Applications of these rules are discussed in the context of the thermodynamics of cold and dense QCD, where it is argued that they facilitate an extension of the Equation of State of cold quark matter to higher perturbative orders.
Cite
@article{arxiv.1609.04339,
title = {On high-order perturbative calculations at finite density},
author = {Ioan Ghisoiu and Tyler Gorda and Aleksi Kurkela and Paul Romatschke and Matias Säppi and Aleksi Vuorinen},
journal= {arXiv preprint arXiv:1609.04339},
year = {2017}
}
Comments
22 pages, 3 figures; v2: discussion extended and references added