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Related papers: Nonperturbative infrared fixed point in sextet QCD

200 papers

We unveil the general features of the phase diagram for any gauge theory with fermions transforming according to distinct representations of the underlying gauge group, at the four-loop order. We classify and analyze the zeros of the…

High Energy Physics - Phenomenology · Physics 2017-09-19 Claudio Pica , Francesco Sannino

We study the SU(3) gauge theory with twelve flavours of fermions in the fundamental representation as a prototype of non-Abelian gauge theories inside the conformal window. Guided by the pattern of underlying symmetries, chiral and…

High Energy Physics - Lattice · Physics 2015-06-23 M. P. Lombardo , K. Miura , T. J. Nunes da Silva , E. Pallante

We present a new lattice study of the discrete beta function for SU(3) gauge theory with Nf=8 massless flavors of fermions in the fundamental representation. Using the gradient flow running coupling, and comparing two different nHYP-smeared…

High Energy Physics - Lattice · Physics 2015-06-30 Anna Hasenfratz , David Schaich , Aarti Veernala

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

We discuss qualitative behavior of the SU(N) gauge beta functions in QCD with many massless flavors. Non-perturbative beta functions can be obtained by extracting the renormalized trajectories in the exact renormalization group framework.…

High Energy Physics - Phenomenology · Physics 2015-05-27 Yuki Kusafuka , Haruhiko Terao

Using lattice simulations, we study the extent of the conformal window for an $\text{SU}(3)$ gauge theory with $N_f$ Dirac fermions in the fundamental representation. We present evidence that the infrared behavior is conformal for $12 \leq…

High Energy Physics - Phenomenology · Physics 2009-12-15 Thomas Appelquist , George T. Fleming , Ethan T. Neil

We study the evolution of the coupling in SU(2) gauge field theory with $N_f=8$ fundamental fermion flavors on the lattice. This model is expected to have an infrared fixed point at high coupling. We use HEX-smeared Wilson-clover action,…

High Energy Physics - Lattice · Physics 2017-07-18 Viljami Leino , Jarno Rantaharju , Teemu Rantalaiho , Kari Rummukainen , Joni M. Suorsa , Kimmo Tuominen

QCD with gauge group $SU(N_c)$ flows to an interacting conformal fixed point in three spacetime dimensions when the number of four-component Dirac fermions $N_f \gg N_c$. We study the stability of this fixed point via the…

High Energy Physics - Theory · Physics 2016-09-28 Hart Goldman , Michael Mulligan

We introduce a gauge invariant and string independent two-point fermion correlator which is analyzed in the context of the Schwinger model (QED_2). We also derive an effective infrared worldline action for this correlator, thus enabling the…

High Energy Physics - Theory · Physics 2008-11-26 D. G. Barci , L. E. Oxman , S. P. Sorella

The dynamics with an infrared stable fixed point in the conformal window in QCD like theories (with a relatively large number of fermion flavors) is studied. The dependence of masses of colorless bound states on a bare fermion mass is…

High Energy Physics - Phenomenology · Physics 2009-10-31 V. A. Miransky

Starting from the strong-coupling SU(2) Wilson action in D=3 dimensions, we derive an effective, semi-local action on a lattice of spacing L times the spacing of the original lattice. It is shown that beyond the adjoint color-screening…

High Energy Physics - Lattice · Physics 2009-10-31 M. Faber , J. Greensite , S. Olejnik

We investigate the infrared dynamics of a nonsupersymmetric SU(X) gauge theory featuring an adjoint fermion, Nf Dirac flavors and an Higgs-like complex Nf x Nf scalar which is a gauge singlet. We first establish the existence of an infrared…

High Energy Physics - Phenomenology · Physics 2015-05-28 Oleg Antipin , Matin Mojaza , Francesco Sannino

We show that the discrepancy on the critical flavor number of fermions $N_f^c$ for the appearance of the infrared fixed point based on the t'Hooft anomaly matching condition and derived from the Schr\"odinger functional method ($N_f^c\sim…

High Energy Physics - Lattice · Physics 2010-08-23 Sadataka Furui

SU(2) gauge theory with Nf=24 massless fermions is non-interacting at long distances, i.e. it has an infrared fixed point at vanishing coupling. With massive fermions the fermions are expected to decouple at energy scales below the fermion…

High Energy Physics - Lattice · Physics 2022-09-26 Tobias Rindlisbacher , Kari Rummukainen , Ahmed Salami , Kimmo Tuominen

The existence of non-trivial IR and UV fixed points in gauge theories as a function of the number of fermion flavors and bare coupling is discussed in the light of recent work. It is pointed out that in fact only a small subset of potential…

High Energy Physics - Phenomenology · Physics 2014-01-23 E. T. Tomboulis

Walking technicolor theory attempts to realize electroweak symmetry breaking as the spontaneous chiral symmetry breakdown caused by the gauge dynamics with slowly varying gauge coupling constant and large mass anomalous dimension.…

High Energy Physics - Lattice · Physics 2011-05-12 M. Hayakawa , K. -I. Ishikawa , Y. Osaki , S. Takeda , S. Uno , N. Yamada

We study the SU(3) lattice gauge theory, with two flavors of sextet Wilson-clover fermions, near its finite-temperature phase transition. We find metastable states that have Wilson line expectation values whose complex phases are near 2pi/3…

High Energy Physics - Lattice · Physics 2010-01-27 Olga Machtey , Benjamin Svetitsky

In previous work we have presented scheme-independent calculations of physical properties of operators at a conformally invariant infrared fixed point in an asymptotically free gauge theory with gauge group $G$ and $N_f$ fermions in a…

High Energy Physics - Theory · Physics 2018-11-14 Thomas A. Ryttov , Robert Shrock

We present a non-perturbative lattice study of SU(4) gauge theory with two flavors of fermions in the fundamental representation and two in the two-index antisymmetric representation: a theory closely related to a minimal…

High Energy Physics - Lattice · Physics 2019-09-10 Guido Cossu , Luigi Del Debbio , Marco Panero , David Preti

We study non-perturbative improvement in SU(3) lattice gauge theory coupled to fermions in the fundamental and two-index symmetric representations. Our lattice action is defined with hypercubic smeared links incorporated into the…

High Energy Physics - Lattice · Physics 2011-06-07 Yigal Shamir , Benjamin Svetitsky , Evgeny Yurkovsky