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Related papers: Gradient flow and IR fixed point in SU(2) with Nf=…

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We use lattice simulations and the continuous renormalization-group method, based on the gradient flow, to study a candidate theory of composite Higgs and a partially composite top. The model is an SU(4) gauge theory with four Dirac…

High Energy Physics - Lattice · Physics 2023-06-21 Anna Hasenfratz , Ethan T. Neil , Yigal Shamir , Benjamin Svetitsky , Oliver Witzel

We complete a program of study of SU(N) gauge theories coupled to two flavors of fermions in the two-index symmetric representation by performing numerical simulations in SU(4). The beta function, defined and calculated via the…

High Energy Physics - Lattice · Physics 2013-05-30 Thomas DeGrand , Yigal Shamir , Benjamin Svetitsky

Walking technicolor is a mechanism for electroweak symmetry breaking without Higgs field. The Higgs mechanism is provided by chiral symmetry breaking in the technicolor theory. An essential ingredient is the vicinity to an IR fixed point,…

High Energy Physics - Lattice · Physics 2011-04-14 Luigi Del Debbio , Biagio Lucini , Agostino Patella , Claudio Pica , Antonio Rago

The existence of an U(2)xU(2)-symmetric fixed point in the chiral linear sigma model is confirmed using the Functional Renormalization Group (FRG). Its stability properties and the implications for the order of the chiral phase transition…

High Energy Physics - Theory · Physics 2015-06-23 Mara Grahl

We have carried out a Schrodinger functional (SF) calculation for the SU(3) lattice gauge theory with two flavors of Wilson fermions in the sextet representation of the gauge group. We find that the discrete beta function, which governs the…

High Energy Physics - Lattice · Physics 2008-11-26 Yigal Shamir , Benjamin Svetitsky , Thomas DeGrand

We report new results from high precision analysis of an important BSM gauge theory with twelve massless fermion flavors in the fundamental representation of the SU(3) color gauge group. The range of the renormalized gauge coupling is…

High Energy Physics - Lattice · Physics 2018-02-14 Zoltan Fodor , Kieran Holland , Julius Kuti , Daniel Nogradi , Chik Him Wong

The chiral fermion model with local multifermion interactions proposed in Nucl. Phys. B486 (1997) 282 and Phys. Rev. D61 (2000) 054502 processes an exact SU_L(2) chiral gauge symmetry and SU_L(2) by U_R(1) chiral flavour symmetry on a…

High Energy Physics - Lattice · Physics 2009-10-31 She-Sheng Xue

After some introductory comments on the peculiar features of slowly running theories, I will report results obtained using the Schrodinger functional technique for two gauge theories that are believed to lie near the bottom of the conformal…

High Energy Physics - Lattice · Physics 2013-10-10 Thomas DeGrand , Yigal Shamir , Benjamin Svetitsky

Using a finite volume Gradient Flow (GF) renormalization scheme with Schr\"odinger Functional (SF) boundary conditions, we compute the non-perturbative running coupling in the range $2.2 \lesssim {\bar g}_\mathrm{GF}^2(L) \lesssim 13$.…

High Energy Physics - Lattice · Physics 2017-02-01 Mattia Dalla Brida , Patrick Fritzsch , Tomasz Korzec , Alberto Ramos , Stefan Sint , Rainer Sommer

SU(2) gauge theory with two fermions transforming under the adjoint representation may appear conformal or almost conformal in the infrared, and is one of the candidate theories for building models for technicolor. Early lattice Monte Carlo…

High Energy Physics - Lattice · Physics 2015-05-20 Tuomas Karavirta , Anne Mykkanen , Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

The most general SU(3)-singlet space of gauged N=8 supergravity in four-dimensions is studied recently. The SU(3)-invariant six scalar fields are realized by six real four-forms. A family of holographic N=1 supersymmetric RG flows on…

High Energy Physics - Theory · Physics 2014-11-20 Changhyun Ahn

We investigate QCD with a large number of massless flavors with the aid of renormalization group flow equations. We determine the critical number of flavors separating the phases with and without chiral symmetry breaking in SU(Nc) gauge…

High Energy Physics - Phenomenology · Physics 2009-01-07 Holger Gies , Joerg Jaeckel

We simulate $ SU(2) $ lattice gauge theory using dynamical reduced staggered fermions. The latter lead to two rather than four Dirac fermions in the continuum limit. We review the derivation and properties of reduced staggered fermions and…

High Energy Physics - Lattice · Physics 2019-01-23 Simon Catterall , Nouman Butt

Extended simulation results and their analysis are reported in a strongly coupled gauge theory with twelve fermion flavors in the fundamental SU(3) color representation. The conformality of the model is probed using mass deformed conformal…

High Energy Physics - Lattice · Physics 2012-11-20 Zoltan Fodor , Kieran Holland , Julius Kuti , Daniel Nogradi , Chris Schroeder , Chik Him Wong

We present a major update on our investigations of SU(2) gauge theory with one Dirac flavor in the adjoint representation on the lattice. In particular we consider larger volumes, as well as four different values of the gauge coupling. We…

High Energy Physics - Lattice · Physics 2022-04-18 Andreas Athenodorou , Ed Bennett , Georg Bergner , Biagio Lucini

We study the flow equation of the O($N$) $\varphi^4$ model in $d$ dimensions at the next-to-leading order (NLO) in the $1/N$ expansion. Using the Schwinger-Dyson equation, we derive 2-pt and 4-pt functions of flowed fields. As the first…

High Energy Physics - Theory · Physics 2019-12-06 Sinya Aoki , Janos Balog , Tetsuya Onogi , Peter Weisz

We study the global symmetries of SU(2) gauge theory with N flavors of staggered fermions in the presence of a chemical potential. We motivate the special interest of the case N=1 (staggered) with fermions in the adjoint representation of…

High Energy Physics - Lattice · Physics 2009-10-31 Simon Hands , Istvan Montvay , Manfred Oevers , Luigi Scorzato , Jonivar Skullerud

We compute the renormalized running coupling of SU(3) gauge theory coupled to N_f = 2 flavors of massless Dirac fermions in the 2-index-symmetric (sextet) representation. This model is of particular interest as a minimal realization of the…

High Energy Physics - Lattice · Physics 2015-09-17 Zoltan Fodor , Kieran Holland , Julius Kuti , Santanu Mondal , Daniel Nogradi , Chik Him Wong

The gradient flow is a valuable tool for the lattice community, with applications from scale-setting to implementing chiral fermions. Here I focus on the gradient flow as a means to suppress power-divergent mixing. Power-divergent mixing…

High Energy Physics - Lattice · Physics 2015-12-02 Christopher Monahan

We review the gradient flow for gauge and fermion fields and its applications to lattice gauge theory computations. Using specific examples, we discuss the interplay between perturbative and non-perturbative calculations in the context of…

High Energy Physics - Lattice · Physics 2023-01-19 Andrea Shindler