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Related papers: Relations and representations of QCD amplitudes

200 papers

In this paper, we investigate tree-level scattering amplitude relations in $U(N)$ non-linear sigma model. We use Cayley parametrization. As was shown in the recent works [23,24] both on-shell amplitudes and off-shell currents with odd…

High Energy Physics - Theory · Physics 2015-06-17 Gang Chen , Yi-Jian Du

In this series of lectures the basic ideas of the $1/m_Q$ expansion in QCD ($m_Q$ is the mass of a heavy quark) are outlined. Applications to exclusive and inclusive decays are given.

High Energy Physics - Phenomenology · Physics 2009-10-28 Thomas Mannel

I review some recent work that describes the close analogy between self-dual Yang--Mills amplitudes and QCD amplitudes with external gluons of positive helicity. This analogy is carried at tree level for amplitudes with two external quarks…

High Energy Physics - Theory · Physics 2009-10-30 Daniel Cangemi

We generalize the scattering equations to include both massless and massive particles. We construct an expression for the tree-level n-point amplitude with n-2 gluons or gravitons and a pair of massive scalars in arbitrary spacetime…

High Energy Physics - Theory · Physics 2015-06-22 Stephen G. Naculich

In this introductory article a brief description of Quantum Field Theories (QFT) is presented with emphasis on the distinction between strongly and weakly coupled theories. A case is made for using numerical simulations to solve QCD, the…

High Energy Physics - Lattice · Physics 2007-05-23 Rajan Gupta

We describe a new set of public, self-contained, and versatile computational tools for the investigation, manipulation, and evaluation of tree-level amplitudes in pure (super)Yang-Mills and (super)Gravity, $\phi^p$-scalar field theory, and…

High Energy Physics - Theory · Physics 2024-01-01 Jacob L. Bourjaily

These lectures describe the use of effective field theories to extrapolate results from the parameter region where numerical simulations of lattice QCD are possible to the physical parameters (physical quark masses, infinite volume,…

High Energy Physics - Lattice · Physics 2007-05-23 Stephen. R. Sharpe

We study the twisted $N=2$ supersymmetric Yang-Mills theory coupled with the hypermultiplets (TQCD). We suggest that the family of TQCD can be served as a powerful tool for studying the quantum field theoretic properties of the underlying…

High Energy Physics - Theory · Physics 2015-06-26 Seungjoon Hyun , Jaemo Park , Jae-Suk Park

This thesis aims at providing better understanding of the perturbative expansion of gauge theories with and without supersymmetry. At tree level, the BCFW recursion relations are analyzed with respect to their validity for general off-shell…

High Energy Physics - Theory · Physics 2014-09-30 Alexander Ochirov

Color-ordered amplitudes in gauge theories satisfy non-linear identities involving amplitude products of different helicity configurations. We consider the origin of such identities and connect them to the Kawai-Lewellen-Tye (KLT) relations…

High Energy Physics - Theory · Physics 2011-01-20 N. E. J. Bjerrum-Bohr , Poul H. Damgaard , Bo Feng , Thomas Sondergaard

We investigate the existence of relations for finite one-loop amplitudes in Yang-Mills theory. Using a diagrammatic formalism and a remarkable connection between tree and loop level, we deduce sequences of amplitude relations for any number…

High Energy Physics - Theory · Physics 2015-05-27 N. E. J. Bjerrum-Bohr , Poul H. Damgaard , Henrik Johansson , Thomas Sondergaard

This paper studies various properties of amplitudes in 3d super Yang Mills theory. First we explain how to obtain the amplitudes of 3d super Yang Mills theories from 4d super Yang Mills theories and obtain their helicity structure. Next, we…

High Energy Physics - Theory · Physics 2015-06-05 Arthur E. Lipstein , Lionel Mason

In this letter, we extend the tree-level Kawai--Lewellen--Tye (KLT) and Bern--Carrasco--Johansson (BCJ) amplitude relations to loop integrands of gauge theory and gravity. By rearranging the propagators of gauge and gravity loop integrands,…

High Energy Physics - Theory · Physics 2017-06-15 Song He , Oliver Schlotterer

We review recent progress in Non-Relativistic QCD and in related Non-Relativistic Effective Field Theories with emphasis on the applications to heavy quarkonia.

High Energy Physics - Phenomenology · Physics 2008-11-26 Nora Brambilla

The theory talks at Moriond QCD and High-Energy Interactions 2025 covered the full range of scales from BSM, top, Higgs, EW, and hard QCD physics, through resummation, factorisation, and PDFs, to hadronic, heavy-ion, nonperturbative, and…

High Energy Physics - Phenomenology · Physics 2025-06-18 Peter Skands

We present a set of one-loop integral coefficient relations in QCD. The unitarity method is useful for exposing one-loop amplitudes in terms of tree amplitudes. The coefficient relations are induced by tree-level BCJ amplitude relations. We…

High Energy Physics - Theory · Physics 2016-03-30 David Chester

We present the complete map of any pair of super Yang-Mills theories to supergravity theories as dictated by the KLT relations in four dimensions. Symmetries and the full set of associated vanishing identities are derived. A graphical…

High Energy Physics - Theory · Physics 2015-06-05 Poul H. Damgaard , Rijun Huang , Thomas Sondergaard , Yang Zhang

We discuss the spectrum of open string and point particle excitations in QCD with various source representations. Some general relations are introduced and lattice results presented. In particular we discuss the short-distance behaviour,…

High Energy Physics - Phenomenology · Physics 2009-11-10 Gunnar S. Bali

We discuss a general model for effective quantum field theories (QFTs), which for example comprises quantum chromodynamics and quantum electrodynamics. We assume in the model a perturbative expansion of the Lagrangian with respect to a…

Mathematical Physics · Physics 2013-02-19 Andreas Raab

I discuss application of the BLM method to obtain commensurate scale relations connecting QCD exclusive amplitudes to other observables, in particular the heavy quark potential.

High Energy Physics - Phenomenology · Physics 2007-05-23 David G. Robertson