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A quantum processor to import, process, and export optical quantum states is a common core technology enabling various photonic quantum information processing. However, there has been no photonic processor which is simultaneously universal,…

Quantum Physics · Physics 2021-11-16 Yutaro Enomoto , Kazuma Yonezu , Yosuke Mitsuhashi , Kan Takase , Shuntaro Takeda

We compute the one-loop QCD amplitudes for the decay of an off-shell vector boson with vector couplings into a quark-antiquark pair accompanied by two gluons keeping, for the first time, all orders in the number of colours. Together with…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. M. Campbell , E. W. N. Glover , D. J. Miller

In this presentation we review the current status in the automated evaluation of scattering amplitudes, with particular attention to the developments related with NLO calculations, which led to the construction of powerful multi-purpose…

High Energy Physics - Phenomenology · Physics 2015-08-11 Giovanni Ossola

We present results for the complete one-loop electroweak logarithmic corrections for general processes at high energies and fixed angles. Our results are applicable to arbitrary matrix elements that are not mass-suppressed. We give explicit…

High Energy Physics - Phenomenology · Physics 2011-09-13 Ansgar Denner , Stefano Pozzorini

We present the complete set of Feynman rules producing the rational terms of kind R_2 needed to perform any 1-loop calculation in the Electroweak Standard Model. Our formulae are given both in the R_xi gauge and in the Unitary gauge,…

High Energy Physics - Phenomenology · Physics 2011-01-17 M. V. Garzelli , I. Malamos , R. Pittau

We present a new approximation technique for quantum field theory. The standard one-loop result is used as a seed for a recursive formula that gives a sequence of improved Gaussian approximations for the generating functional. In a…

High Energy Physics - Theory · Physics 2011-08-08 Antun Balaz , Aleksandar Belic , Aleksandar Bogojevic

In the recent years there has been an enormous development in the evaluation of higher order quantum corrections. An essential ingredient in the practical calculations is provided by vacuum diagrams, i.e. integrals without external momenta.…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Steinhauser

We present a method for the integrand-level reduction of two-loop helicity amplitudes in both $d=4-2\epsilon$ and $d=4$ dimensions. The amplitude is expressed in terms of a set of Feynman integrals and their coefficients that depend on the…

High Energy Physics - Phenomenology · Physics 2025-11-14 Giuseppe Bevilacqua , Dhimiter Canko , Costas Papadopoulos , Aris Spourdalakis

We give an overview of state-of-the-art multi-loop Feynman diagram computations, and explain how we use symbolic manipulation to generate renormalized integrals that are then evaluated numerically. We explain how we automate BPHZ…

High Energy Physics - Phenomenology · Physics 2007-12-07 A. D. Kennedy , T. Binoth , T. Rippon

We present a description of calculations of the amplitude for E+ E- --> F anti-F process with account of electroweak and QED one-loop corrections. This study is performed within the framework of the project SANC. The calculations are done…

High Energy Physics - Phenomenology · Physics 2011-01-13 A. Andonov , D. Bardin , S. Bondarenko , P. Christova , L. Kalinovskaya , G. Nanava

We present new versions of the Mathematica package FeynCalc and the FeynHelpers add-on that represent an important contribution to the collection of public codes for semi-automatic evaluation of multiloop Feynman diagrams. FeynHelpers…

High Energy Physics - Phenomenology · Physics 2025-12-24 Vladyslav Shtabovenko

The complete set of Feynman rules for the rational part R of QCD corrections in the MSSM are calculated at the one-loop level, which can be very useful in the next-to-leading order calculations in supersymmetric models. Our results are…

High Energy Physics - Phenomenology · Physics 2015-06-05 Hua-Sheng Shao , Yu-Jie Zhang

FormCalc is a Mathematica package for the automatic computation of tree-level and one-loop Feynman amplitudes. It accepts diagrams generated by FeynArts, simplifies them, and generates a complete Fortran code for their numerical evaluation.…

High Energy Physics - Phenomenology · Physics 2009-11-10 T. Hahn

The lectures are a practical introduction to perturbative calculations in QED and QCD. I discuss methods of calculation of one- and two-loop diagrams in dimensional regularization, MSbar and on-shell renormalization schemes, decoupling of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrey Grozin

A method for calculating loop amplitudes at the multiboson threshold is presented, based on Feynman-diagram techniques. We explicitly calculate the one-loop amplitudes in both $\phi^4$-symmetric and broken symmetry cases, using dimensional…

High Energy Physics - Phenomenology · Physics 2009-10-22 E. N. Argyres , Ronald H. P. Kleiss , Costas G. Papadopoulos

This article reviews on-shell methods for analytic computation of loop amplitudes, emphasizing techniques based on unitarity cuts. Unitarity techniques are formulated generally but have been especially useful for calculating one-loop…

High Energy Physics - Theory · Physics 2015-05-20 Ruth Britto

Nonadiabatic holonomic quantum computation provides the means to perform fast and robust quantum gates by utilizing the resilience of non-Abelian geometric phases to fluctuations of the path in state space. While the original scheme [New J.…

Quantum Physics · Physics 2016-11-14 Emmi Herterich , Erik Sjöqvist

We discuss the current status of our automatic perturbation theory program as applied to Fermilab Fermions. We give an overview of our methods, a discussion of tree level matching, and one loop results for the coefficients of the higher…

High Energy Physics - Lattice · Physics 2009-11-07 Matthew Nobes , Howard Trottier

We present results on the two-loop leading and angular-dependent next-to-leading logarithmic virtual corrections to arbitrary processes at energies above the electroweak scale. In the `t Hooft-Feynman gauge the relevant Feynman diagrams…

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

We present the complete automation of the computation of one-loop QCD corrections, including UV renormalization, to an arbitrary scattering process in the Standard Model. This is achieved by embedding the OPP integrand reduction technique,…

High Energy Physics - Phenomenology · Physics 2015-05-27 Valentin Hirschi , Rikkert Frederix , Stefano Frixione , Maria Vittoria Garzelli , Fabio Maltoni , Roberto Pittau