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Related papers: The diamond rule for multi-loop Feynman diagrams

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We introduce a novel, systematic method for the complete symbolic reduction of multi-loop Feynman integrals, leveraging the power of generating functions. The differential equations governing these generating functions naturally yield…

High Energy Physics - Phenomenology · Physics 2026-01-30 Bo Feng , Xiang Li , Yuanche Liu , Yan-Qing Ma , Yang Zhang

New algebraic approach to analytical calculations of D-dimensional integrals for multi-loop Feynman diagrams is proposed. We show that the known analytical methods of evaluation of multi-loop Feynman integrals, such as integration by parts…

High Energy Physics - Theory · Physics 2010-04-05 A. P. Isaev

A modular application of the integration by fractional expansion (IBFE) method for evaluating Feynman diagrams is extended to diagrams that contain loop triangle subdiagrams in their geometry. The technique is based in the replacement of…

High Energy Physics - Theory · Physics 2009-07-09 Ivan Gonzalez , Ivan Schmidt

Several powerful techniques for evaluating massless scalar Feynman diagrams are developed, viz: the solution of recurrence relations to evaluate diagrams with arbitrary numbers of loops in $n=4-2\omega$ dimensions; the discovery and use of…

High Energy Physics - Theory · Physics 2016-04-28 David J. Broadhurst

N=4 supersymmetric Yang-Mills theory exhibits a rather surprising duality of Wilson-loop vacuum expectation values and scattering amplitudes. In this paper, we investigate this correspondence at the diagram level. We find that one-loop…

High Energy Physics - Theory · Physics 2015-03-17 Charalampos Anastasiou , Andrea Banfi

Negative dimensional integration is a step further dimensional regularization ideas. In this approach, based on the principle of analytic continuation, Feynman integrals are polynomial ones and for this reason very simple to handle,…

High Energy Physics - Theory · Physics 2009-10-30 Alfredo T. Suzuki , Alexandre G. M. Schmidt

We compute the two and three loop corrections to the beta function for Yang-Mills theories in the background gauge field method and using the background gauge field as the only source. The calculations are based on the separation of the one…

High Energy Physics - Phenomenology · Physics 2015-06-04 Renata Jora

Recently, loop integrands for certain Yang-Mills scattering amplitudes and correlation functions have been shown to be systematically expressible in dlog form, raising the possibility that these loop integrals can be performed directly…

High Energy Physics - Theory · Physics 2015-06-16 Arthur E. Lipstein , Lionel Mason

Scattering amplitudes at loop level can be expressed in terms of Feynman integrals. The latter satisfy partial differential equations in the kinematical variables. We argue that a good choice of basis for (multi-)loop integrals can lead to…

High Energy Physics - Theory · Physics 2013-06-26 Johannes M. Henn

For the calculation of multi-loop Feynman integrals, a novel numerical method, the Direct Computation Method (DCM) is developed. It is a combination of a numerical integration and a series extrapolation. In principle, DCM can handle…

High Energy Physics - Phenomenology · Physics 2012-01-31 K. Kato , E. de Doncker , N. Hamaguchi , T. Ishikawa , T. Koike , Y. Kurihara , Y. Shimizu , F. Yuasa

We present an algorithm to compute arbitrary multi-loop massive Feynman diagrams in the region where the typical energy scale \sqrt{s} is much larger than the typical mass scale M, i.e. s>>M^2, while various different energy and mass…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , S. Pozzorini

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

Relations between multiple unitarity cuts and coproducts of Feynman integrals are extended to allow for internal masses. These masses introduce new branch cuts, whose discontinuities can be derived by placing single propagators on shell and…

High Energy Physics - Theory · Physics 2015-04-02 Samuel Abreu , Ruth Britto , Hanna Grönqvist

Higher order corrections in perturbative quantum field theory are required for precise theoretical analysis to investigate new physics beyond the Standard Model. This indicates that we need to evaluate Feynman loop diagram with multi-loop…

High Energy Physics - Phenomenology · Physics 2014-12-02 Shinji Motoki , Hiroshi Daisaka , Naohito Nakasato , Tadashi Ishikawa , Fukuko Yuasa , Toshiyuki Fukushige , Atsushi Kawai , Junichiro Makino

Finite Feynman integrals have been advocated as the optimal components for constructing a basis of master integrals in multiloop calculations, due to their improved analytic and numerical properties. In this paper, we show how the Loop-Tree…

Higher-order diagrams required for radiative corrections to mixed electroweak and QCD processes at the LHC and anticipated future colliders will require numerically stable representations of the associated Feynman diagrams. The…

Mathematical Physics · Physics 2011-10-25 S. A. Yost , V. V. Bytev , M. Yu. Kalmykov , B. A. Kniehl , B. F. L. Ward

The differential-reduction algorithm, which allows one to express generalized hypergeometric functions with parameters of arbitrary values in terms of such functions with parameters whose values differ from the original ones by integers, is…

High Energy Physics - Theory · Physics 2010-05-19 Vladimir V. Bytev , Mikhail Yu. Kalmykov , Bernd A. Kniehl

In many field theoretical models one has to resum two- and four-legged subdiagrams in order to determine their behaviour. In this article we present a novel formalism which does this in a nice way. It is based on the central limit theorem…

Statistical Mechanics · Physics 2008-11-26 Detlef Lehmann

One-loop integrands in Cachazo-He-Yuan (CHY) formula, which is based on the forward limit of tree-level amplitudes, involves linear propagators that are different from quadratic ones in traditional Feynman diagrams. In this paper, we…

High Energy Physics - Theory · Physics 2024-12-23 Chongsi Xie , Yi-Jian Du

We describe an efficient practical procedure for enumerating and regrouping vacuum Feynman graphs of a given order in perturbation theory. The method is based on a combination of Schwinger-Dyson equations and the two-particle-irreducible…

High Energy Physics - Phenomenology · Physics 2009-11-07 K. Kajantie , M. Laine , Y. Schroder