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Related papers: A Course in Amplitudes

200 papers

We review current efficient techniques for the construction of multi-leg and multi-loop on-shell scattering amplitudes in supersymmetric gauge theories. Examples in the maximally supersymmetric Yang-Mills theory in four dimensions are…

High Energy Physics - Theory · Physics 2015-05-20 R. Roiban

Recent progress in unitarity techniques for one-loop scattering amplitudes makes a numerical implementation of this method possible. We present a 4-dimensional unitarity method for calculating the cut-constructible part of amplitudes and…

High Energy Physics - Phenomenology · Physics 2009-09-17 R. K. Ellis , W. T. Giele , Z. Kunszt

We generalise the reconstruction theorem of Stern, Sazdjian, and Fuchs based on the dispersion relations to the case of the (2 -> 2) scattering of all the pseudoscalar octet mesons (pi, K, eta). We formulate it in a general way and include…

High Energy Physics - Phenomenology · Physics 2008-12-30 M. Zdrahal , J. Novotny

We review some recent developments in the understanding of field theories in the perturbative regime. In particular, we discuss the notions of analyticity, unitarity and locality, and therefore the singularity structure of scattering…

High Energy Physics - Theory · Physics 2015-06-18 Paolo Benincasa

Results for four-, five-, and six-parton tree amplitudes for massive quark-antiquark scattering with gluons are calculated using the recursion relations of Britto, Cachazo, Feng, and Witten. The required diagrams are generated using shifts…

High Energy Physics - Phenomenology · Physics 2008-11-26 Anthony Hall

We present an extension of the spinor integration formalism of one loop amplitudes from the double-cut to the single-cut case. This technique can be applied for the computation of the tadpole coefficients. Moreover we describe an off-shell…

High Energy Physics - Phenomenology · Physics 2012-02-14 Ruth Britto , Edoardo Mirabella

Twistor ideas have led to a number of recent advances in our understanding of scattering amplitudes. Much of this work has been indirect, determining the twistor space support of scattering amplitudes by examining the amplitudes in momentum…

High Energy Physics - Theory · Physics 2014-11-18 Lionel Mason , David Skinner

Attached to both Yang-Mills and General Relativity about Minkowski spacetime are distinguished gauge independent objects known as the on-shell tree scattering amplitudes. We reinterpret and rigorously construct them as $L_\infty$ minimal…

Mathematical Physics · Physics 2022-07-12 Andrea Nützi , Michael Reiterer

We present a new method for computing multi-loop scattering amplitudes in Quantum Field Theory. It extends the Generalized Unitarity method by constraining not only the integrand of the amplitude but also its full integrated form. Our…

High Energy Physics - Theory · Physics 2025-12-18 Piotr Bargiela

In this review we describe a non-trivial relationship between perturbative gauge theory and gravity scattering amplitudes. At the semi-classical or tree level, the scattering amplitudes of gravity theories in flat space can be expressed as…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Zvi Bern

The Cachazo-Svrcek-Witten approach to perturbative gauge theory is extended to gauge theories with quarks and gluinos. All googly amplitudes with quark-antiquark pairs and gluinos are computed and shown to agree with the previously known…

High Energy Physics - Theory · Physics 2010-02-03 Jun-Bao Wu , Chuan-Jie Zhu

This thesis is focused on the development of new mathematical methods for computing multi-loop scattering amplitudes in gauge theories. In this work we combine, for the first time, the unitarity-based construction for integrands, and the…

High Energy Physics - Phenomenology · Physics 2014-10-21 Ulrich Schubert

Based on the joined work performed together with Z. Bern, D. Forde, and D. Kosower [1], in this talk it is recalled the (twistor-motivated) diagrammatic formalism describing tree-level scattering amplitudes presented by Cachazo, Svr\v{c}ek…

High Energy Physics - Phenomenology · Physics 2015-06-25 Pierpaolo Mastrolia

We show that on-shell recursion relations hold for tree amplitudes in generic two derivative theories of multiple particle species and diverse spins. For example, in a gauge theory coupled to scalars and fermions, any amplitude with at…

High Energy Physics - Theory · Physics 2011-03-02 Clifford Cheung

After a brief review (in the first part) of some relevant properties of the high-energy parton-parton scattering amplitudes, in the second part we shall discuss the infrared finiteness and some analyticity properties of the loop-loop…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Meggiolaro

Using relationships between open and closed strings, we present a construction of tree-level scattering amplitudes for gravitons minimally coupled to matter in terms of gauge theory partial amplitudes. In particular, we present examples of…

High Energy Physics - Theory · Physics 2009-10-31 Z. Bern , A. De Freitas , H. L. Wong

Recently two of the authors presented a spinorial extension of the scattering equations, the `polarized scattering equations' that incorporates spinor polarization data. These led to new worldsheet amplitude formulae for a variety of gauge,…

High Energy Physics - Theory · Physics 2020-12-02 Giulia Albonico , Yvonne Geyer , Lionel Mason

As a step toward satisfactory understanding of the quantum dynamics of Dirichlet \break (D-) particles, the amplitude for the basic process describing the scattering of two quantized D-particles is computed in bosonic string theory. The…

High Energy Physics - Theory · Physics 2007-05-23 Yoichi Kazama

We calculate on-shell scattering amplitudes involving fermions at the tree level in open superstring field theory. We confirm that four-point and five-point amplitudes in the world-sheet path integral with the standard prescription using…

High Energy Physics - Theory · Physics 2016-12-05 Hiroshi Kunitomo , Yuji Okawa , Hiroki Sukeno , Tomoyuki Takezaki

We use the recently developed massive spinor-helicity formalism [1] of Arkani- Hamed et al. to propose a new class of recursion relations for tree-level amplitudes in gauge theories. These relations are based on a combined complex…

High Energy Physics - Theory · Physics 2021-05-13 Sourav Ballav , Arkajyoti Manna