English
Related papers

Related papers: Evaluating double and triple (?) boxes

200 papers

Local, manifestly dual-conformally invariant loop integrands are now known for all finite quantities associated with observables in planar, maximally supersymmetric Yang-Mills theory through three loops. These representations, however, are…

High Energy Physics - Theory · Physics 2019-05-01 Jacob L. Bourjaily , Falko Dulat , Erik Panzer

The operator approach to analytical evaluation of multi-loop Feynman diagrams is proposed. We show that the known analytical methods of evaluation of massless Feynman integrals, such as the integration by parts method and the method of…

High Energy Physics - Theory · Physics 2008-11-26 A. P. Isaev

We explore inequality constraints as a new tool for numerically evaluating Feynman integrals. A convergent Feynman integral is non-negative if the integrand is non-negative in either loop momentum space or Feynman parameter space. Applying…

High Energy Physics - Phenomenology · Physics 2023-10-05 Mao Zeng

We describe a method to numerically compute multi-loop integrals, depending on one dimensionless parameter $x$ and the dimension $d$, in the whole kinematic range of $x$. The method is based on differential equations, which, however, do not…

High Energy Physics - Phenomenology · Physics 2021-10-13 Matteo Fael , Fabian Lange , Kay Schönwald , Matthias Steinhauser

We apply a recently suggested new strategy to solve differential equations for Feynman integrals. We develop this method further by analyzing asymptotic expansions of the integrals. We argue that this allows the systematic application of…

High Energy Physics - Theory · Physics 2015-06-18 Johannes M. Henn , Alexander V. Smirnov , Vladimir A. Smirnov

A new approach to compute Feynman Integrals is presented. It relies on an integral representation of a given Feynman Integral in terms of simpler ones. Using this approach, we present, for the first time, results for a certain family of…

High Energy Physics - Phenomenology · Physics 2020-03-18 Costas G. Papadopoulos , Christopher Wever

In this talk we discuss a class of Feynman integrals, which can be expressed to all orders in the dimensional regularisation parameter as iterated integrals of modular forms. We review the mathematical prerequisites related to elliptic…

High Energy Physics - Phenomenology · Physics 2018-07-04 Luise Adams , Stefan Weinzierl

In this work, we calculate two-loop six-point planar massless Feynman integrals at higher orders in the dimensional regulator $\epsilon$, corresponding to higher transcendental weights. In previous works, these integrals were calculated up…

High Energy Physics - Phenomenology · Physics 2026-04-03 Yuanche Liu , Antonela Matijašić , Tiziano Peraro , Yingxuan Xu , Zihua Yang , Yang Zhang

A recently proposed scheme for numerical evaluation of Feynman diagrams is extended to cover all two-loop two-point functions with arbitrary internal and external masses. The adopted algorithm is a modification of the one proposed by F. V.…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. Passarino , S. Uccirati

We present analytic results on physical kinematics for four integral families that are relevant to the production of two off-shell vector bosons with different masses. Our study consists of a ladder-box, a tennis-court, and two reducible…

High Energy Physics - Phenomenology · Physics 2025-11-05 Dhimiter Canko , Mattia Pozzoli

We study a recently-proposed approach to the numerical evaluation of multi-loop Feynman integrals using available sector decomposition programs. As our main example, we consider the two-loop integrals for the $\alpha \alpha_s$ corrections…

High Energy Physics - Phenomenology · Physics 2017-11-08 Andreas von Manteuffel , Robert M. Schabinger

General prescriptions for evaluation of coefficients at arbitrary powers and logarithms in the asymptotic expansion of Feynman diagrams in the Sudakov limit are discussed and illustrated by two-loop examples. Peculiarities connected with…

High Energy Physics - Phenomenology · Physics 2009-10-31 V. A. Smirnov , E. R. Rakhmetov

Renormalization of massless Feynman amplitudes in $x$-space is reexamined here, using almost exclusively real-variable methods. We compute a wealth of concrete examples by means of recursive extension of distributions. This allows us to…

High Energy Physics - Theory · Physics 2017-02-23 José M. Gracia-Bondía , Heidy Gutiérrez , Joseph C. Várilly

We study the elliptic double-box integral, which contributes to generic massless QFTs and is the only contribution to a particular 10-point scattering amplitude in N=4 SYM theory. Based on a Feynman parametrization, we express this integral…

High Energy Physics - Theory · Physics 2022-01-07 Alexander Kristensson , Matthias Wilhelm , Chi Zhang

In this paper we develop further and refine the method of differential equations for computing Feynman integrals. In particular, we show that an additional iterative structure emerges for finite loop integrals. As a concrete non-trivial…

High Energy Physics - Theory · Physics 2015-06-19 Simon Caron-Huot , Johannes M. Henn

For certain dimensionally-regulated one-, two- and three-loop diagrams, problems of constructing the epsilon-expansion and the analytic continuation of the results are studied. In some examples, an arbitrary term of the epsilon-expansion…

High Energy Physics - Theory · Physics 2025-10-20 A. I. Davydychev , M. Yu. Kalmykov

This paper continues our previous study of Feynman integrals in configuration spaces and their algebro-geometric and motivic aspects. We consider here both massless and massive Feynman amplitudes, from the point of view of potential theory.…

Mathematical Physics · Physics 2013-08-28 Ozgur Ceyhan , Matilde Marcolli

We elaborate on the application of on-shell and unitarity-based methods for evaluating renormalization group coefficients, and generalize this framework to account for the mixing of operators with different dimensions and leading mass…

High Energy Physics - Phenomenology · Physics 2026-05-26 L. C. Bresciani , G. Levati , P. Mastrolia , P. Paradisi

We identify cluster algebras for planar kinematics of conformal Feynman integrals in four dimensions, as sub-algebras of that for top-dimensional $G(4,n)$ corresponding to $n$-point massless kinematics. We provide evidence that they encode…

High Energy Physics - Theory · Physics 2026-04-16 Song He , Zhenjie Li , Qinglin Yang

The diagrammatic coaction encodes the analytic structure of Feynman integrals by mapping any given Feynman diagram into a tensor product of diagrams defined by contractions and cuts of the original diagram. Feynman integrals evaluate to…

High Energy Physics - Theory · Physics 2021-11-04 Einan Gardi , Aris Ioannou