https://neckpinch.com/authors/nicolo-drago/New arXiv papers by Nicolò Drago, from Neckpinch Tue, 10 Nov 2026 04:10:28 GMT https://neckpinch.com/papers/1809.07652/arxiv:1809.07652Thu, 20 Sep 2018 00:00:00 GMTMauro Carfora, Claudio Dappiaggi, Nicolò Drago, Paolo Rinaldi — The perturbative approach to nonlinear Sigma models and the associated renormalization group flow are discussed within the framework of Euclidean algebraic quantum field theory and of the principle of general local covariance. In particular we show in an Euclidean setting how to define Wick ordered powers of the underlying quantum fields and we classify the freedom in such procedure by extending to this setting a recent construction of Khavkine, Melati and Moretti for vector valued free fields. As a by-product of such classification, we prove that, at first order in perturbation theory, the renormalization group flow of the nonlinear Sigma model is the Ricci flow.Ricci flowPhysics