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We present a Mathematica package which finds a basis of master integrals for the Feynman integral reduction. In this basis the dependence on the dimensional regularization in the denominators factorizes in kinematic independent polynomials.

High Energy Physics - Phenomenology · Physics 2020-04-03 Johann Usovitsch

Different mathematical methods have been applied to obtain the analytic result for the massless triangle Feynman diagram yielding a sum of four linearly independent hypergeometric functions $F_4$. In this paper I work out the diagram and…

High Energy Physics - Theory · Physics 2008-08-12 Alfredo Takashi Suzuki

In this paper we exploit factorisation properties of Picard-Fuchs operators to decouple differential equations for multi-scale Feynman integrals. The algorithm reduces the differential equations to blocks of the size of the order of the…

High Energy Physics - Phenomenology · Physics 2017-04-12 Luise Adams , Ekta Chaubey , Stefan Weinzierl

We compute three-point functions of general operators in the su(1|1) sector of planar N = 4 SYM in the weak coupling regime, both at tree-level and one-loop. Each operator is represented by a closed spin chain Bethe state characterized by a…

High Energy Physics - Theory · Physics 2015-06-19 Joao Caetano , Thiago Fleury

In the dynamical triangulation model of 4D euclidean quantum gravity we measure two-point functions of the scalar curvature as a function of the geodesic distance. To get the correlations it turns out that we need to subtract a squared…

High Energy Physics - Lattice · Physics 2009-07-09 Bas V. de Bakker , Jan Smit

In this paper it is shown how the generating functional for Green's functions in relativistic quantum field theory and in thermal field theory can be evaluated in terms of a standard quantum mechanical path integral. With this calculational…

High Energy Physics - Theory · Physics 2011-07-19 D. G. C. McKeon , A. Rebhan

We present a new method for the momentum expansion of Feynman integrals with arbitrary masses and any number of loops and external momenta. By using the parametric representation we derive a generating function for the coefficients of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 O. V. Tarasov

We compute all planar two-loop six-point Feynman integrals entering scattering observables in massless gauge theories such as QCD. A central result of this paper is the formulation of the differential-equations method under the algebraic…

High Energy Physics - Phenomenology · Physics 2024-12-31 Samuel Abreu , Pier Francesco Monni , Ben Page , Johann Usovitsch

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 introduce a new method for computing massless Feynman integrals analytically in parametric form. An analysis of the method yields a criterion for a primitive Feynman graph $G$ to evaluate to multiple zeta values. The criterion depends…

Algebraic Geometry · Mathematics 2009-03-24 Francis Brown

In order to calculate cross sections with a large number of particles/jets in the final state at next-to-leading order, one has to reduce the occurring scalar and tensor one-loop integrals to a small set of known integrals. In massless…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Heinrich , T. Binoth

Hypergeometric function method is proposed to calculate the scalar integrals of Feynman diagrams. For the scalar integral of three-loop vacuum diagram with four-propagator, we verify the equivalency of Feynman parametrization and the…

High Energy Physics - Phenomenology · Physics 2019-09-04 Zhi-Hua Gu , Hai-Bin Zhang

A short review of expansion by regions is presented. It is a well-known strategy to obtain an expansion of a given multiloop Feynman integral in a given limit where some kinematic invariants and/or masses have certain scaling measured in…

High Energy Physics - Theory · Physics 2024-06-18 Vladimir A. Smirnov

Quantum corrections significantly influence the quantities observed in modern particle physics. The corresponding theoretical computations are usually quite lengthy which makes their automation mandatory. This review reports on the current…

High Energy Physics - Phenomenology · Physics 2011-08-17 R. Harlander , M. Steinhauser

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

We present a new method for numerically computing generic multi-loop Feynman integrals. The method relies on an iterative application of Feynman's trick for combining two propagators. Each application of Feynman's trick introduces a…

High Energy Physics - Phenomenology · Physics 2022-06-30 Martijn Hidding , Johann Usovitsch

A short review of the method for the tensor reduction of Feynman integrals based on recurrence relations with respect to space-time dimension d- is given. A solution of the difference equation with respect to d for the n - point one-loop…

High Energy Physics - Phenomenology · Physics 2009-11-07 O. V. Tarasov

Motivated by the precision results in the electroweak theory studies of two-loopFeynman diagrams are performed. Specifically this paper gives a contribution to the knowledge of massive two-loop self-energy diagrams in arbitrary and…

High Energy Physics - Phenomenology · Physics 2011-09-30 S. Bauberger , F. A. Berends , M. Boehm , M. Buza

We provide high-energy approximations for all one-loop scalar 3- and 4-point functions and the corresponding tensor integrals that appear in scattering processes with four external on-shell particles. Our expressions are valid if all…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Roth , A. Denner

Feynman integral reduction based on intersection theory provides an alternative to the traditional integration-by-parts method, yet its practical application has been constrained by the large number of variables required in the computation.…

High Energy Physics - Theory · Physics 2026-04-08 Li-Hong Huang , Yan-Qing Ma , Ziwen Wang , Li Lin Yang