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Title: Conformal window of SU(N) gauge theories with fermions in higher dimensional representations

Abstract

We study the phase diagram as a function of the number of colors and flavors of asymptotically free nonsupersymmetric theories with matter in higher-dimensional representations of arbitrary SU(N) gauge groups. Since matter in higher-dimensional representations screens more than in the fundamental a general feature is that a lower number of flavors is needed to achieve a near-conformal theory.

Authors:
;  [1];  [2]
  1. Institute for Theoretical Physics, Heidelberg University, Heidelberg (Germany) and Niels Bohr Institute, Copenhagen (Denmark)
  2. (Denmark) and Niels Bohr Institute, Copenhagen (Denmark)
Publication Date:
OSTI Identifier:
21020430
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.085018; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COLOR MODEL; CONFORMAL INVARIANCE; FERMIONS; FLAVOR MODEL; GAUGE INVARIANCE; MANY-DIMENSIONAL CALCULATIONS; PHASE DIAGRAMS; SU GROUPS

Citation Formats

Dietrich, Dennis D., Sannino, Francesco, and Department of Physics and Chemistry, University of Southern Denmark, Odense. Conformal window of SU(N) gauge theories with fermions in higher dimensional representations. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.085018.
Dietrich, Dennis D., Sannino, Francesco, & Department of Physics and Chemistry, University of Southern Denmark, Odense. Conformal window of SU(N) gauge theories with fermions in higher dimensional representations. United States. doi:10.1103/PHYSREVD.75.085018.
Dietrich, Dennis D., Sannino, Francesco, and Department of Physics and Chemistry, University of Southern Denmark, Odense. Sun . "Conformal window of SU(N) gauge theories with fermions in higher dimensional representations". United States. doi:10.1103/PHYSREVD.75.085018.
@article{osti_21020430,
title = {Conformal window of SU(N) gauge theories with fermions in higher dimensional representations},
author = {Dietrich, Dennis D. and Sannino, Francesco and Department of Physics and Chemistry, University of Southern Denmark, Odense},
abstractNote = {We study the phase diagram as a function of the number of colors and flavors of asymptotically free nonsupersymmetric theories with matter in higher-dimensional representations of arbitrary SU(N) gauge groups. Since matter in higher-dimensional representations screens more than in the fundamental a general feature is that a lower number of flavors is needed to achieve a near-conformal theory.},
doi = {10.1103/PHYSREVD.75.085018},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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  • We discuss the existence of a conformal phase in SU(N) gauge theories in four dimensions. In this lattice study, we explore the model in the bare parameter space, varying the lattice coupling and bare mass. Simulations are carried out with three colors and 12 flavors of dynamical staggered fermions in the fundamental representation. The analysis of the chiral order parameter and the mass spectrum of the theory indicates the restoration of chiral symmetry at zero temperature and the presence of a Coulomb-like phase, depicting a scenario compatible with the existence of an infrared stable fixed point at nonzero coupling. Ourmore » analysis supports the conclusion that the onset of the conformal window for QCD-like theories is smaller than N{sub f}=12, before the loss of asymptotic freedom at 16 and 1/2 flavors. We discuss open questions and future directions.« less