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Related papers: Loop Amplitudes and Quantum Homotopy Algebras

200 papers

We describe new on-shell recursion relations for tree-amplitudes in N=1 and N=2 gauge theories and use these to show that the structure of the S-matrix in pure N=1 and N=2 gauge theories resembles that of pure Yang-Mills. We proceed to…

High Energy Physics - Theory · Physics 2010-05-25 Shailesh Lal , Suvrat Raju

This thesis describes some of the recent (and some less recent) developments in calculational techniques for scattering amplitudes in quantum field theory. The focus is on on-shell recursion relations in complex momenta and on the use of…

High Energy Physics - Theory · Physics 2008-04-22 Kasper Risager

Scattering equations for tree-level amplitudes are viewed in the context of string theory. As a result of the comparison we are led to define a new dual model which coincides with string theory in both the small and large $\alpha'$ limit,…

High Energy Physics - Theory · Physics 2015-06-19 N. E. J Bjerrum-Bohr , P. H. Damgaard , P. Tourkine , P. Vanhove

We conjecture a new set of analytic relations for scattering amplitudes in planar N=4 super Yang-Mills theory. They generalise the Steinmann relations and are expressed in terms of the cluster algebras associated to Gr(4,n). In terms of the…

High Energy Physics - Theory · Physics 2018-04-25 James Drummond , Jack Foster , Omer Gurdogan

We analyze the off-shell scattering amplitudes in the framework of the light-front perturbation theory. It is shown that the previously derived recursion relation between tree level off-shell amplitudes in this formalism actually resums…

High Energy Physics - Phenomenology · Physics 2015-06-24 C. Cruz-Santiago , P. Kotko , A. Stasto

We characterise possible identities among the two-loop partial amplitudes of gluon scattering in Yang-Mills theory. We use known amplitudes in an exhaustive search to identify potential new relations. We find two candidate relations which…

High Energy Physics - Theory · Physics 2023-08-15 David C. Dunbar

We study a novel geometric expansion for scattering amplitudes in the planar sector of N=4 super Yang-Mills theory, in the context of the Amplituhedron which reproduces the all-loop integrand as a canonical differential form on the positive…

High Energy Physics - Theory · Physics 2024-01-01 Taro V. Brown , Umut Oktem , Shruti Paranjape , Jaroslav Trnka

We show how to apply the BCFW recursion relation to Feynman loop integrals with the help of the Feynman-tree theorem. We deconstruct in this way all Feynman diagrams in terms of on-shell subamplitudes. Every cut originating from the…

High Energy Physics - Theory · Physics 2016-05-18 M. Maniatis , C. M. Reyes

We present an amplitude-generating formula in renormalizable quantum field theory. It reflects the self-similarity of loop amplitudes, in which an amplitude can also be a subamplitude of another. Amplitudes are generated by a small number…

High Energy Physics - Theory · Physics 2025-03-19 Kang-Sin Choi

We present new relations for scattering amplitudes of color ordered gluons, massive quarks and scalars minimally coupled to gravity. Tree-level amplitudes of arbitrary matter and gluon multiplicities involving one graviton are reduced to…

High Energy Physics - Theory · Physics 2018-07-18 Jan Plefka , Wadim Wormsbecher

These lectures are centred around tree-level scattering amplitudes in pure Yang-Mills theories, the most prominent example is given by the tree-level gluon amplitudes of QCD. I will discuss several ways of computing these amplitudes,…

High Energy Physics - Theory · Physics 2017-01-23 Stefan Weinzierl

Perturbatively around flat space, the scattering amplitudes of gravity are related to those of Yang-Mills by colour-kinematic duality, under which gravitational amplitudes are obtained as the 'double copy' of the corresponding gauge theory…

High Energy Physics - Theory · Physics 2017-12-20 Tim Adamo , Eduardo Casali , Lionel Mason , Stefan Nekovar

This is the first in a series of papers presenting a new understanding of scattering amplitudes based on fundamentally combinatorial ideas in the kinematic space of the scattering data. We study the simplest theory of colored scalar…

High Energy Physics - Theory · Physics 2024-10-01 N. Arkani-Hamed , H. Frost , G. Salvatori , P-G. Plamondon , H. Thomas

Multiloop scattering amplitudes describing the quantum fluctuations at high-energy scattering processes are the main bottleneck in perturbative quantum field theory. The loop-tree duality is a novel method aimed at overcoming this…

These notes were given as lectures at the CERN Winter School on Supergravity, Strings and Gauge Theory 2010. We describe the structure of scattering amplitudes in gauge theories, focussing on the maximally supersymmetric theory to highlight…

High Energy Physics - Theory · Physics 2015-03-17 J. M. Drummond

We derive new amplitudes relations revealing a hidden unity among wide-ranging theories in arbitrary spacetime dimensions. Our results rely on a set of Lorentz invariant differential operators which transmute physical tree-level scattering…

High Energy Physics - Theory · Physics 2018-04-04 Clifford Cheung , Chia-Hsien Shen , Congkao Wen

Quantum field theory provides us with the means to calculate scattering amplitudes. In recent years a dramatic new development has lead to great simplification of such calculations. This is based on the discovery of the``amplituhedron'' in…

High Energy Physics - Theory · Physics 2022-08-24 Deepak Vaid , Devadharshini Suresh

Recently it has been argued that tree-level scattering amplitudes in N=4 Yang-Mills theory are uniquely determined by a careful study of their superconformal and Yangian symmetries. However, at one-loop order these symmetries are known to…

High Energy Physics - Theory · Physics 2010-04-22 Niklas Beisert , Johannes Henn , Tristan McLoughlin , Jan Plefka

Scattering amplitudes in planar super-Yang-Mills theory satisfy several basic physical and mathematical constraints, including physical constraints on their branch cut structure and various empirically discovered connections to the…

High Energy Physics - Theory · Physics 2017-07-05 Thomas Harrington , Marcus Spradlin

We identify a large class of one-loop amplitudes for massless particles that can be constructed via unitarity from tree amplitudes, without any ambiguities. One-loop amplitudes for massless supersymmetric gauge theories fall into this…

High Energy Physics - Phenomenology · Physics 2010-11-15 Z. Bern , L. Dixon , D. C. Dunbar , D. A. Kosower