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Related papers: Integration by parts: An introduction

200 papers

Many multi-loop calculations make use of integration by parts relations to reduce the large number of complicated Feynman integrals that arise in such calculations to a simpler basis of master integrals. Recently, Gluza, Kajda, and Kosower…

High Energy Physics - Phenomenology · Physics 2015-06-03 Robert M. Schabinger

This course on Feynman integrals starts from the basics, requiring only knowledge from special relativity and undergraduate mathematics. Topics from quantum field theory and advanced mathematics are introduced as they are needed. The course…

High Energy Physics - Theory · Physics 2022-06-15 Stefan Weinzierl

In this talk, we discuss how ideas from geometry help to improve Feynman integral reduction and the construction of $\varepsilon$-factorised differential equations. In particular, we outline a systematic procedure to obtain an…

We present a novel approach to optimizing the reduction of Feynman integrals using integration-by-parts identities. By developing a priority function through the FunSearch algorithm, which combines large language models and genetic…

High Energy Physics - Phenomenology · Physics 2025-02-14 Zhuo-Yang Song , Tong-Zhi Yang , Qing-Hong Cao , Ming-xing Luo , Hua Xing Zhu

In these lectures I will give an introduction to Feynman integrals. In the first part of the course I review the basics of the perturbative expansion in quantum field theories. In the second part of the course I will discuss more advanced…

High Energy Physics - Phenomenology · Physics 2010-05-12 Stefan Weinzierl

We illustrate the usefulness of functional equations in establishing relationships between master integrals under the integration-by-parts reduction procedure by considering a certain two-loop propagator-type diagram as an example.

High Energy Physics - Theory · Physics 2016-02-02 Bernd A. Kniehl , Oleg V. Tarasov

We introduce an algebro-geometrically motived integration-by-parts (IBP) reduction method for multi-loop and multi-scale Feynman integrals, using a framework for massively parallel computations in computer algebra. This framework combines…

We show that the integration-by-parts reductions of various two-loop integral topologies can be efficiently obtained by applying unitarity cuts to a specific set of subgraphs and solving associated polynomial (syzygy) equations.

High Energy Physics - Theory · Physics 2016-07-08 Kasper J. Larsen , Yang Zhang

We present an interesting study of Feynman integral reduction that does not employ integration-by-parts identities. Our approach proceeds by studying the equivalence relations of integral contours in the Feynman parameterization. We find…

High Energy Physics - Theory · Physics 2026-04-30 Ziwen Wang , Li Lin Yang

Intersection numbers are rational scalar products among functions that admit suitable integral representations, such as Feynman integrals. Using these scalar products, the decomposition of Feynman integrals into a basis of linearly…

High Energy Physics - Phenomenology · Physics 2023-10-16 Gaia Fontana , Tiziano Peraro

We present the powerful module-intersection integration-by-parts (IBP) method, suitable for multi-loop and multi-scale Feynman integral reduction. Utilizing modern computational algebraic geometry techniques, this new method successfully…

High Energy Physics - Theory · Physics 2018-09-11 Janko Boehm , Alessandro Georgoudis , Kasper J. Larsen , Hans Schoenemann , Yang Zhang

Feynman integral reduction by means of integration-by-parts identities is a major power gadget in a theorist toolbox indispensable for calculation of multiloop quantum effects relevant for particle phenomenology and formal theory alike. An…

High Energy Physics - Phenomenology · Physics 2024-02-13 A. V. Belitsky , A. A. Kokosinskaya , A. V. Smirnov , V. V. Voevodin , M. Zeng

The reduction of Feynman integrals to a basis of linearly independent master integrals is a pivotal step in loop calculations, but also one of the main bottlenecks. In this paper, we assess the impact of using transverse integration…

High Energy Physics - Phenomenology · Physics 2025-06-17 Vsevolod Chestnov , Gaia Fontana , Tiziano Peraro

Phase space cuts are implemented by inserting Heaviside theta functions in the integrands of momentum-space Feynman integrals. By directly parametrizing theta functions and constructing integration-by-parts (IBP) identities in the…

High Energy Physics - Phenomenology · Physics 2021-03-29 Wen Chen

In this paper we show how to improve and extend the Integration by Fractional Expansion technique (IBFE) by applying it to certain families of scalar massive Feynman diagrams. The strategy is based on combining this method together with the…

High Energy Physics - Theory · Physics 2010-02-03 Ivan Gonzalez , Marcelo Loewe

We review the Laporta algorithm for the reduction of scalar integrals to the master integrals and the differential equations technique for their evaluation. We discuss the use of the basis of harmonic polylogarithms for the analytical…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Bonciani

We present a detailed description of the recent idea for a direct decomposition of Feynman integrals onto a basis of master integrals by projections, as well as a direct derivation of the differential equations satisfied by the master…

The integration by parts recurrence relations allow to reduce some Feynman integrals to more simple ones (with some lines missing). Nevertheless the possibility of such reduction for the given particular integral was unclear. The recently…

High Energy Physics - Phenomenology · Physics 2009-10-31 P. A. Baikov

An algorithm for the reduction of one-loop n-point tensor integrals to basic integrals is proposed. We transform tensor integrals to scalar integrals with shifted dimension and reduce these by recurrence relations to integrals in generic…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Fleischer , F. Jegerlehner , O. V. Tarasov

The reduction of Feynman integrals to a basis of master integrals plays a crucial role for many high-precision calculations and Kira is one of the leading tools for this task. In these proceedings we discuss some of the new features and…

High Energy Physics - Phenomenology · Physics 2024-07-02 Fabian Lange , Johann Usovitsch , Zihao Wu