Mon·Nov 26, 2007Monday·November 26, 2007

1. 01*

   Supersymmetry Inspired QCD Beta Function

   Thomas A. Ryttov (CERN and NBI)🇨🇭 · Francesco Sannino (University of Southern Denmark and NBI)🇩🇰

   We propose an all orders beta function for ordinary Yang-Mills theories with or without fermions inspired by the Novikov-Shifman-Vainshtein-Zakharov beta function of N=1 supersymmetric gauge theories. The beta function allows us to bound the conformal window. When restricting to one adjoint Weyl fermion we show how the proposed beta function matches the one of supersymmetric Yang-Mills theory. The running of the pure Yang-Mills coupling is computed and the deviation from the two loop result is presented. We then compare the deviation with the one obtained from lattice data also with respect to the two loop running.

   ↳ hep-thhep-lathep-phPRD(2008)·195 citations
2. 02*

   On the large N expansion in hyperbolic sigma-models

   Max Niedermaier🇫🇷 · Erhard Seiler🇩🇪

   Invariant correlation functions for $\mathrm{SO}(1,N)$ hyperbolic sigma-models are investigated. The existence of a large $N$ asymptotic expansion is proven on finite lattices of dimension $d\ge 2$. The unique saddle point configuration is characterized by a negative gap vanishing at least like 1/V with the volume. Technical difficulties compared to the compact case are bypassed using horospherical coordinates and the matrix-tree theorem.

   ↳ math-phhep-lathep-thmath.MPJ.Math.Phys.(2008)·3 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.