English
Related papers

Related papers: New Developments in FeynCalc 9.0

200 papers

We present a method for rewriting dimensionally regulated Feynman parameter integrals in the Minkowski regime as a sum of real, positive integrands multiplied by complex prefactors. This representation eliminates the need for contour…

High Energy Physics - Phenomenology · Physics 2025-07-01 Stephen Jones , Anton Olsson , Thomas Stone

New methods for obtaining functional equations for Feynman integrals are presented. Application of these methods for finding functional equations for various one- and two- loop integrals described in detail. It is shown that with the aid of…

High Energy Physics - Phenomenology · Physics 2015-12-31 O. V. Tarasov

A new kind of cut diagram is introduced to sum Feynman diagrams with nonabelian vertices. Unlike the Cutkosky diagrams which compute the discontinuity of single Feynman diagrams, the nonabelian cut diagrams represent a resummation of both…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. S. Lam

Feynman diagrams may be evaluated by Mellin-Barnes representations of their Feynman parameter integrals in d=4-2\eps dimensions. Recently, the Mathematica toolkit AMBRE has been developed for the automatic derivation of such representations…

High Energy Physics - Phenomenology · Physics 2009-04-16 J. Gluza , F. Haas , K. Kajda , T. Riemann

We find that all Feynman integrals (FIs), having any number of loops, can be completely determined once linear relations between FIs are provided. Therefore, FIs computation is conceptually changed to a linear algebraic problem. Examples up…

High Energy Physics - Phenomenology · Physics 2022-12-07 Zhi-Feng Liu , Yan-Qing Ma

We invent an automated method for computing the divergent part of Feynman integrals in dimensional regularization. Our method exploits simplifications from four-dimensional integration-by-parts identities. Leveraging algorithms from the…

High Energy Physics - Theory · Physics 2023-09-19 Johannes Henn , Rourou Ma , Kai Yan , Yang Zhang

Feynman integrals play a central role in the modern scattering amplitudes research program. Advancing our methods for evaluating Feynman integrals will, therefore, strengthen our ability to compare theoretical predictions with data from…

High Energy Physics - Theory · Physics 2024-01-03 Henrik J. Munch

An algorithm for the systematic analytical approximation of multi-scale Feynman integrals is presented. The algorithm produces algebraic expressions as functions of the kinematical parameters and mass scales appearing in the Feynman…

High Energy Physics - Phenomenology · Physics 2018-09-26 Sophia Borowka , Thomas Gehrmann , Daniel Hulme

We develop a new representation for the integrals associated with Feynman diagrams. This leads directly to a novel method for the numerical evaluation of these integrals, which avoids the use of Monte Carlo techniques. Our approach is based…

High Energy Physics - Phenomenology · Physics 2009-10-31 Richard Easther , Gerald Guralnik , Stephen Hahn

We present a user-friendly software for photonic analog quantum computing with an installable MATLAB package and the graphical user interface (GUI) that allows for convenient operation without requiring programming skills. Arbitrary…

Quantum Physics · Physics 2018-10-05 Hao Tang , Yan-Yan Zhu , Jun Gao , Marcus Lee , Peng-Cheng Lai , Xian-Min Jin

Systems of integration-by-parts identities play an important role in simplifying the higher-loop Feynman integrals that arise in quantum field theory. Solving these systems is equivalent to reducing integrals containing numerator products…

High Energy Physics - Phenomenology · Physics 2018-07-18 David A. Kosower

We introduce a machine-learning framework based on symbolic regression to extract the full symbol alphabet of multi-loop Feynman integrals. By targeting the analytic structure rather than reduction, the method is broadly applicable and…

High Energy Physics - Phenomenology · Physics 2025-10-28 Yuanche Liu , Yingxuan Xu , Yang Zhang

Some of the difficulties faced when calculating multi-loop amplitudes with several mass scales are reviewed. We then focus on one particular difficulty, the evaluation of the Feynman integrals, and introduce the program pySecDec which can…

High Energy Physics - Phenomenology · Physics 2018-06-08 S. P. Jones , B. Ruijl

The program package SecDec is presented, allowing the numerical evaluation of multi-loop integrals. The restriction to Euclidean kinematics of version 1.0 has been lifted: thresholds can be handled by an automated deformation of the…

High Energy Physics - Phenomenology · Physics 2012-09-28 Sophia Borowka , Gudrun Heinrich

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

We present version 3.4 of the CalcHEP software package which is designed for effective evaluation and simulation of high energy physics collider processes at parton level. The main features of CalcHEP are the computation of Feynman…

High Energy Physics - Phenomenology · Physics 2015-06-05 Alexander Belyaev , Neil D. Christensen , Alexander Pukhov

We present a historiographical review of algorithms and computer codes developed for solving integration-by-parts relations for Feynman integrals. This procedure is one of the key steps in the evaluation of Feynman integrals, since it…

High Energy Physics - Theory · Physics 2025-11-13 Alexander Smirnov , Vladimir Smirnov

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

Over the last year significant progress was made in the understanding of the computation of Feynman integrals using differential equations. These lectures give a review of these developments, while not assuming any prior knowledge of the…

High Energy Physics - Phenomenology · Physics 2015-06-23 Johannes M. Henn

We describe our method for rewriting dimensionally regulated Feynman parameter integrals in the Minkowski regime as a sum of real, positive integrands multiplied by complex prefactors. This representation eliminates the need for a contour…

High Energy Physics - Phenomenology · Physics 2026-03-06 Stephen P. Jones , Anton Olsson , Thomas Stone