English
Related papers

Related papers: A simple method for multi-leg loop calculations

200 papers

An improved PV-reduction method for one-loop integrals with auxiliary vector $R$ has been proposed in \cite{Feng:2021enk,Hu:2021nia}. It has also been shown that the new method is a self-completed method in \cite{Feng:2022uqp}. Analytic…

High Energy Physics - Phenomenology · Physics 2022-08-24 Bo Feng , Chang Hu , Tingfei Li , Yuekai Song

A simplified differential equations approach for Master Integrals is presented. It allows to express them, straightforwardly, in terms of Goncharov Polylogarithms. As a proof-of-concept of the proposed method, results at one and two loops…

High Energy Physics - Phenomenology · Physics 2017-09-15 Costas G. Papadopoulos

Tensor methods are among the most prominent tools for the numerical solution of high-dimensional problems where functions of multiple variables have to be approximated. These methods exploit the tensor structure of function spaces and apply…

Numerical Analysis · Mathematics 2021-02-01 Anthony Nouy

In this talk we review the GOLEM approach to one-loop calculations and present an automated implementation of this technique. This method is based on Feynman diagrams and an advanced reduction of one-loop tensor integrals which avoids…

We consider the problem of recovering a low-multilinear-rank tensor from a small amount of linear measurements. We show that the Riemannian gradient algorithm initialized by one step of iterative hard thresholding can reconstruct an…

Numerical Analysis · Mathematics 2021-01-14 Jian-Feng Cai , Lizhang Miao , Yang Wang , Yin Xian

By a tensor we mean an element of a tensor product of vector spaces over a field. Up to a choice of bases in factors of tensor products, every tensor may be coordinatized, that is, represented as an array consisting of numbers. This note is…

Functional Analysis · Mathematics 2019-01-11 R. N. Gumerov , A. S. Sharafutdinov

In this paper we have studied the most general generating function of reduction for one loop integrals with arbitrary tensor structure in numerator and arbitrary power distribution of propagators in denominator. Using IBP relations, we have…

High Energy Physics - Phenomenology · Physics 2024-11-12 Bo Feng , Chang Hu , Jiyuan Shen , Yaobo Zhang

We calculate the complete set of two-loop Master Integrals with two off mass-shell legs with massless internal propagators, that contribute to amplitudes of diboson $V_1V_2$ production at the LHC. This is done with the Simplified…

High Energy Physics - Phenomenology · Physics 2015-07-22 Costas G. Papadopoulos , Damiano Tommasini , Christopher Wever

We propose a sampling-based method for computing the tensor ring (TR) decomposition of a data tensor. The method uses leverage score sampled alternating least squares to fit the TR cores in an iterative fashion. By taking advantage of the…

Numerical Analysis · Mathematics 2021-07-12 Osman Asif Malik , Stephen Becker

Using the matrix product state (MPS) representation of the recently proposed tensor ring decompositions, in this paper we propose a tensor completion algorithm, which is an alternating minimization algorithm that alternates over the factors…

Machine Learning · Computer Science 2017-07-27 Wenqi Wang , Vaneet Aggarwal , Shuchin Aeron

Low rank tensor learning, such as tensor completion and multilinear multitask learning, has received much attention in recent years. In this paper, we propose higher order matching pursuit for low rank tensor learning problems with a convex…

Machine Learning · Statistics 2015-03-10 Yuning Yang , Siamak Mehrkanoon , Johan A. K. Suykens

In this work we present recent results on application of low-rank tensor decompositions to modelling of aggregation kinetics taking into account multi-particle collisions (for three and more particles). Such kinetics can be described by…

Numerical Analysis · Mathematics 2020-08-18 Daniil A. Stefonishin , Sergey A. Matveev , Dmitry A. Zheltkov

We present OPITeR, a FORM program for the reduction of multi-loop tensor Feynman integrals. The program can handle tensors, including spinor indices, with rank of up to 20 and can deal with up to 8 independent external momenta. The…

High Energy Physics - Phenomenology · Physics 2025-04-29 Jae Goode , Franz Herzog , Sam Teale

As a key method to deal with loop integrals, Integration-By-Parts (IBP) method can be used to do reduction as well as establish the differential equations for master integrals. However, when talking about tensor reduction, the…

High Energy Physics - Theory · Physics 2022-06-01 Bo Feng , Tingfei Li , Hongbin Wang , Yaobo Zhang

A new approach for the reduction of tensor integrals is described. The standard decomposition \`{a} la Davydychev is applied. Integrals with higher indices are then expressed in terms of scalar higher-dimensional integrals with generic…

High Energy Physics - Phenomenology · Physics 2012-11-19 Jochem Fleischer , Janusz Gluza , Marek Gluza , Tord Riemann , Radomir Sevillano

Extending the method successful for one-loop integrals, the computation of two-loop diagrams with general internal masses is discussed. For the two-loop vertex of non-planar type, as an example, we show a calculation related to…

High Energy Physics - Phenomenology · Physics 2011-03-02 J. FUJIMOTO , Y. SHIMIZU , K. KATO , T. KANEKO

A Mathematica implementation of the program LERG-I is presented that performs the reduction of tensor integrals, encountered in one-loop Feynman diagram calculations, to scalar integrals. The program was originally coded in REDUCE and in…

High Energy Physics - Phenomenology · Physics 2009-10-28 Robin G. Stuart

The goal of this paper is to find a low-rank approximation for a given tensor. Specifically, we give a computable strategy on calculating the rank of a given tensor, based on approximating the solution to an NP-hard problem. In this paper,…

Numerical Analysis · Mathematics 2016-10-20 Xiaofei Wang , Carmeliza Navasca

We study the problem of calculating two-loop three-point diagrams with irreducible numerators (i.e. numerators which cannot be expressed in terms of the denominators). For the case of massless internal particles and arbitrary (off-shell)…

High Energy Physics - Phenomenology · Physics 2014-11-17 Natalia I. Ussyukina , Andrei I. Davydychev

We give a new method for the reduction of tensor integrals to finite integral representations and UV divergent analytic expressions. This includes a new method for the handling of the gamma-algebra. TYPO IN EQUATION (5) CORRECTED, MACROS…

High Energy Physics - Phenomenology · Physics 2009-10-22 Dirk Kreimer