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Related papers: spinney: A Form Library for Helicity Spinors

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Following suggestions of Nekrasov and Siegel, a non-minimal set of fields are added to the pure spinor formalism for the superstring. Twisted $\hat c$=3 N=2 generators are then constructed where the pure spinor BRST operator is the…

High Energy Physics - Theory · Physics 2009-11-11 Nathan Berkovits

We introduce a notion of holonomy in twistor space and construct a holonomy operator by use of a spinor-momenta formalism in twistor space. The holonomy operator gives a monodromy representation of the Knizhnik-Zamolodchikov (KZ) equation,…

High Energy Physics - Theory · Physics 2009-11-09 Yasuhiro Abe

Spinons are among the generic excitations in one-dimensional spin systems, they can be massless or massive. The quantitative description of massive spinons poses a considerable challenge in spite of various variational approaches. We show…

Strongly Correlated Electrons · Physics 2017-05-30 Mohsen Hafez-Torbati , Götz S. Uhrig

A prototype for an extensible interactive graphical term manipulation system is presented that combines pattern matching and nondeterministic evaluation to provide a convenient framework for doing tedious algebraic manipulations that so far…

Symbolic Computation · Computer Science 2007-05-23 Thomas Fischbacher

A method to efficiently compute, in a automatic way, helicity amplitudes for arbitrary scattering processes at leading order in the Standard Model is presented. The scattering amplitude is evaluated recursively through a set of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Costas G. Papadopoulos , Malgorzata Worek

An algorithm is presented that formalizes different steps in a classical Supersymmetric (SUSY) calculation. Based on the algorithm Dill, a symbolic software package, that can perform the calculations, is developed in the Mathematica…

High Energy Physics - Phenomenology · Physics 2009-10-28 Vladan Lucic

In this work we present a mathematical description of how one can produce and read a thin hologram. We use different kinds of waves, such as scalar, vector (electromagnetic field, Maxwell-Proca fields, acoustic waves, etc.). For reading of…

Optics · Physics 2011-09-26 Zoltan Batiz , Bhag C. Chauhan

The discovery of pure spinor formalism makes the computation of superstring scattering amplitudes possible. In this paper, we will illustrate how computer algebra system Cadabra is used in computing the supersymmetric amplitude in pure…

High Energy Physics - Theory · Physics 2016-08-17 Ke-Sheng Sun , Xiang-Mao Ding , Fei Sun , Hai-Bin Zhang

Two-component spinors are the basic ingredients for describing fermions in quantum field theory in four space-time dimensions. We develop and review the techniques of the two-component spinor formalism and provide a complete set of Feynman…

High Energy Physics - Phenomenology · Physics 2022-05-25 Herbi K. Dreiner , Howard E. Haber , Stephen P. Martin

A systematic presentation of spinors in various dimensions is given.

High Energy Physics - Theory · Physics 2007-05-23 M. A. De Andrade , I. V. Vancea

The authors present SHarmonic, a new implementation of the spherical harmonics targeted for electronic-structure calculations. Their approach is to use explicit formulas for the harmonics written in terms of normalized Cartesian…

Computational Physics · Physics 2025-10-08 Xavier Andrade , Jacopo Simoni , Yuan Ping , Tadashi Ogitsu , Alfredo A. Correa

We present Simphony, a free and open-source software toolbox for abstracting and simulating photonic integrated circuits, implemented in Python. The toolbox is both fast and easily extensible; plugins can be written to provide compatibility…

Emerging Technologies · Computer Science 2020-09-14 Sequoia Ploeg , Hyrum Gunther , Ryan M. Camacho

Fortran subroutines to calculate helicity amplitudes with massive spin-3/2 particles, such as massive gravitinos, which couple to the standard model and supersymmetric particles via the supercurrent, are added to the HELAS (HELicity…

High Energy Physics - Phenomenology · Physics 2011-02-09 K. Hagiwara , K. Mawatari , Y. Takaesu

In this paper we present a space-time calculus for symmetric spinors, including a product with a number of index contractions followed by symmetrization. As all operations stay within the class of symmetric spinors, no involved index…

General Relativity and Quantum Cosmology · Physics 2023-03-29 Steffen Aksteiner , Thomas Bäckdahl

We propose a simple heralded amplification scheme for small rotations of the collective spin of an ensemble of particles. Our protocol makes use of two basic primitives for quantum memories, namely partial mapping of light onto an ensemble,…

Quantum Physics · Physics 2015-05-28 Nicolas Brunner , Eugene S. Polzik , Christoph Simon

The unitarity method for calculating one-loop amplitudes provides algorithms of polynomial complexity. This is primarily beneficial for the computation of multi-leg one loop amplitudes and it is therefore of great interest to develop a…

High Energy Physics - Phenomenology · Physics 2009-04-14 R. Keith Ellis , Walter T. Giele , Zoltan Kunszt

In this paper we extend our previous result on the description of the partcle motion in a generalized Heisenberg picture to a relativistic fermion. The operators of the Lorentz algebra in this picture may be regarded as field operators. In…

High Energy Physics - Theory · Physics 2007-05-23 Rudolf A. Frick

We survey some general-purpose symbolic software packages that implement algorithms from enumerative and analytic combinatorics. Software for the following areas is covered: basic combinatorial objects, symbolic combinatorics, P\'olya…

Mathematical Software · Computer Science 2016-01-13 Andrew MacFie

We introduce FORM 4.2, a new minor release of the symbolic manipulation toolkit. We demonstrate several new features, such as a new pattern matching option, new output optimization, and automatic expansion of rational functions.

High Energy Physics - Phenomenology · Physics 2017-07-21 Ben Ruijl , Takahiro Ueda , Jos Vermaseren

The formalism of quantum field theory in operator form, based on the anti self-adjoint operators of the imaginary coordinate and momentum and the self-adjoint operators of the real coordinate, momentum, energy and time, is used in…

General Physics · Physics 2024-06-05 Slobodan Prvanovic