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Related papers: Bootstrapping the QCD soft anomalous dimension

200 papers

We present universal factorization formulas describing the behavior of one-loop QCD amplitudes as external momenta become either soft or collinear. Our results are valid to all orders in the dimensional regularization parameter, $\eps$.…

High Energy Physics - Phenomenology · Physics 2016-08-25 Z. Bern , V. Del Duca , W. B. Kilgore , C. R. Schmidt

We evaluate the one-loop soft current for the emission of two soft gluons or a soft quark-anti-quark pair in massless Quantum Chromodynamics. The results are exact in dimensional regularisation up to a single Feynman integral. Two terms of…

High Energy Physics - Phenomenology · Physics 2023-04-20 Michał Czakon , Felix Eschment , Tom Schellenberger

We present a symbol-level bootstrap construction of the planar, two-loop six-gluon scattering amplitude for the --++++ helicity configuration in QCD, focusing on the maximal weight pieces-the "most complicated terms" in the sense of Lipatov…

High Energy Physics - Theory · Physics 2026-03-24 Sérgio Carrôlo , Dmitry Chicherin , Johannes Henn , Qinglin Yang , Yang Zhang

Gauge theories and perturbative gravity in four dimensions are governed by a tower of infinite-dimensional symmetries which arise from tree-level soft theorems. However, aside from the leading soft theorems which are all-loop exact,…

High Energy Physics - Theory · Physics 2024-12-24 Sangmin Choi , Alok Laddha , Andrea Puhm

We compute the two-loop four-point form factor of a length-3 half-BPS operator in planar N=4 SYM, which belongs to the class of two-loop five-point scattering observables with one off-shell color-singlet leg. A new bootstrapping strategy is…

High Energy Physics - Theory · Physics 2021-10-13 Yuanhong Guo , Lei Wang , Gang Yang

We construct perturbation series for the q-th moment of eigenfunctions of various critical random matrix ensembles in the strong multifractality regime close to localization. Contrary to previous investigations, our results are valid in the…

Quantum Physics · Physics 2015-06-03 E. Bogomolny , O. Giraud

Singular factors originating from the QCD factorisation of scattering amplitudes in soft and collinear limits play a prominent role in both organising and computing high-order perturbative contributions to hard-scattering cross sections. In…

High Energy Physics - Phenomenology · Physics 2022-08-16 Prasanna K. Dhani

1+1 dimensional integrable quantum field theories correspond to a sparse subset of quantum field theories where the calculation of physically interesting observables can be brought to explicit, closed and manageable expressions thanks to…

Mathematical Physics · Physics 2023-05-12 Karol K. Kozlowski

We study massive $2 \to 2$ scattering of identical scalar particles in spacetime dimensions 3 to 11 using non-perturbative S-matrix bootstrap techniques. Treating $d$ as a continuous parameter, we compute two-sided numerical bounds on…

High Energy Physics - Theory · Physics 2026-01-01 Mehmet Asim Gumus , Simon Metayer , Piotr Tourkine

Dyson-Schwinger equations are used to evaluate the 4-loop anomalous dimensions of quenched QED in terms of finite, scheme-independent, 3-loop integrals. Three of the results serve as strong checks of terms from scheme-dependent 4-loop QCD…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. J. Broadhurst

We study the infrared behaviour of tree-level QCD amplitudes and we derive infrared-factorization formulae that are valid at any perturbative order. We explicitly compute all the universal infrared factors that control the singularities in…

High Energy Physics - Phenomenology · Physics 2015-06-25 S. Catani , M. Grazzini

Recently, an all-order conjecture for the anomalous-dimension matrix of n-jet operators in SCET was proposed, which allows one to predict the structure of the infrared divergences of dimensionally regularized, massless gauge-theory…

High Energy Physics - Phenomenology · Physics 2011-12-16 Leonardo Vernazza

We have studied the recently completed analytic all-N expressions for the four-loop anomalous dimensions corresponding to the next-to-next-to-next-to-leading order splitting functions for the non-singlet quark distribution in perturbative…

High Energy Physics - Phenomenology · Physics 2026-05-06 S. Moch , A. Vogt

We study logarithmic conformal field theory (LogCFT) in four dimensions using conformal bootstrap techniques in the large spin limit. We focus on the constraints imposed by conformal symmetry on the four point function of certain…

High Energy Physics - Theory · Physics 2019-12-24 Pinaki Banerjee , Parijat Dey

It is well known that soft singularities of massless amplitudes are significantly simpler than those of massive ones. However, the computation of the soft anomalous dimension (AD) using Wilson-lines correctors is only straightforward in the…

High Energy Physics - Phenomenology · Physics 2025-09-23 Einan Gardi , Zehao Zhu

We derive analytic results for the symbol of certain two-loop Feynman integrals relevant for seven- and eight-point two-loop scattering amplitudes in planar $\mathcal{N}=4$ super-Yang--Mills theory. We use a bootstrap inspired strategy,…

High Energy Physics - Theory · Physics 2018-11-14 Johannes Henn , Enrico Herrmann , Julio Parra-Martinez

We show that for a particular model, the quantum mechanical bootstrap is capable of finding exact results. We consider a solvable system with Hamiltonian $H=SZ(1-Z)S$, where $Z$ and $S$ satisfy canonical commutation relations. While this…

High Energy Physics - Theory · Physics 2024-02-07 Lewis Sword , David Vegh

I present results for two-loop soft anomalous dimensions, which are derived from dimensionally regularized diagrams with eikonal quark lines and control soft-gluon emission in hard-scattering processes. Detailed results for the UV poles of…

High Energy Physics - Phenomenology · Physics 2009-10-06 Nikolaos Kidonakis

In this paper, we study celestial amplitudes of Goldstone bosons and conformal soft theorems. Motivated by the success of soft bootstrap in momentum space and the important role of the soft limit behavior of tree-level amplitudes, our goal…

High Energy Physics - Theory · Physics 2024-01-02 Karol Kampf , Jiri Novotny , Jaroslav Trnka , Petr Vasko

We present a factorization formula for the production of pairs of heavy coloured particles in hadronic collisions at the production threshold, which forms the basis for the resummation of soft gluons and Coulomb gluons. We construct a basis…

High Energy Physics - Phenomenology · Physics 2010-04-08 M. Beneke , P. Falgari , C. Schwinn