|   | 
Details
   web
Records
Author (up) Aguilera-Verdugo, J.D.; Driencourt-Mangin, F.; Hernandez-Pinto, R.J.; Plenter, J.; Prisco, R.M.; Ramirez-Uribe, N.S.; Renteria-Olivo, A.E.; Rodrigo, G.; Sborlini, G.F.R.; Torres Bobadilla, W.J.; Tramontano, F.
Title A Stroll through the Loop-Tree Duality Type Journal Article
Year 2021 Publication Symmetry-Basel Abbreviated Journal Symmetry-Basel
Volume 13 Issue 6 Pages 1029 - 37pp
Keywords Feynman integrals; multi-loop calculations; perturbative QFT; higher orders
Abstract The Loop-Tree Duality (LTD) theorem is an innovative technique to deal with multi-loop scattering amplitudes, leading to integrand-level representations over a Euclidean space. In this article, we review the last developments concerning this framework, focusing on the manifestly causal representation of multi-loop Feynman integrals and scattering amplitudes, and the definition of dual local counter-terms to cancel infrared singularities.
Address [de Jesus Aguilera-Verdugo, Jose; Driencourt-Mangin, Felix; Plenter, Judith; Selomit Ramirez-Uribe, Norma; Ernesto Renteria-Olivo, Andres; Rodrigo, German; Sborlini, German] Univ Valencia, Inst Fis Corpuscular, CSIC, Parc Cient, E-46980 Paterna, Spain, Email: jesus.aguilera@ific.uv.es;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000666742200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4889
Permanent link to this record
 

 
Author (up) Aguilera-Verdugo, J.J.; Driencourt-Mangin, F.; Hernandez-Pinto, R.J.; Plenter, J.; Ramirez-Uribe, S.; Renteria-Olivo, A.E.; Rodrigo, G.; Sborlini, G.F.R.; Torres Bobadilla, W.J.; Tracz, S.
Title Open Loop Amplitudes and Causality to All Orders and Powers from the Loop-Tree Duality Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 124 Issue 21 Pages 211602 - 6pp
Keywords
Abstract Multiloop scattering amplitudes describing the quantum fluctuations at high-energy scattering processes are the main bottleneck in perturbative quantum field theory. The loop-tree duality is a novel method aimed at overcoming this bottleneck by opening the loop amplitudes into trees and combining them at integrand level with the real-emission matrix elements. In this Letter, we generalize the loop-tree duality to all orders in the perturbative expansion by using the complex Lorentz-covariant prescription of the original one-loop formulation. We introduce a series of mutiloop topologies with arbitrary internal configurations and derive very compact and factorizable expressions of their open-to-trees representation in the loop-tree duality formalism. Furthermore, these expressions are entirely independent at integrand level of the initial assignments of momentum flows in the Feynman representation and remarkably free of noncausal singularities. These properties, that we conjecture to hold to other topologies at all orders, provide integrand representations of scattering amplitudes that exhibit manifest causal singular structures and better numerical stability than in other representations.
Address [Jesus Aguilera-Verdugo, J.; Driencourt-Mangin, Felix; Plenter, Judith; Ramirez-Uribe, Selomit; Renteria-Olivo, Andres E.; Rodrigo, German; Sborlini, German F. R.; Torres Bobadilla, William J.; Tracz, Szymon] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient, E-46980 Valencia, Spain, Email: jesus.aguilera@ific.uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000535862200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4404
Permanent link to this record
 

 
Author (up) Aguilera-Verdugo, J.J.; Hernandez-Pinto, R.J.; Rodrigo, G.; Sborlini, G.F.R.; Torres Bobadilla, W.J.
Title Causal representation of multi-loop Feynman integrands within the loop-tree duality Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 69 - 26pp
Keywords Duality in Gauge Field Theories; Perturbative QCD; Scattering Amplitudes
Abstract The numerical evaluation of multi-loop scattering amplitudes in the Feynman representation usually requires to deal with both physical (causal) and unphysical (non-causal) singularities. The loop-tree duality (LTD) offers a powerful framework to easily characterise and distinguish these two types of singularities, and then simplify analytically the underling expressions. In this paper, we work explicitly on the dual representation of multi-loop Feynman integrals generated from three parent topologies, which we refer to as Maximal, Next-to-Maximal and Next-to-Next-to-Maximal loop topologies. In particular, we aim at expressing these dual contributions, independently of the number of loops and internal configurations, in terms of causal propagators only. Thus, providing very compact and causal integrand representations to all orders. In order to do so, we reconstruct their analytic expressions from numerical evaluation over finite fields. This procedure implicitly cancels out all unphysical singularities. We also interpret the result in terms of entangled causal thresholds. In view of the simple structure of the dual expressions, we integrate them numerically up to four loops in integer space-time dimensions, taking advantage of their smooth behaviour at integrand level.
Address [Jesus Aguilera-Verdugo, J.; Rodrigo, German; Sborlini, German F. R.; Torres Bobadilla, William J.] Univ Valencia, Inst Fis Corpuscular, CSIC, Parc Cientif, E-46980 Valencia, Spain, Email: jesus.aguilera@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000609437600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4697
Permanent link to this record
 

 
Author (up) Aguilera-Verdugo, J.J.; Hernandez-Pinto, R.J.; Rodrigo, G.; Sborlini, G.F.R.; Torres Bobadilla, W.J.
Title Mathematical properties of nested residues and their application to multi-loop scattering amplitudes Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 112 - 42pp
Keywords NLO Computations; QCD Phenomenology
Abstract The computation of multi-loop multi-leg scattering amplitudes plays a key role to improve the precision of theoretical predictions for particle physics at high-energy colliders. In this work, we focus on the mathematical properties of the novel integrand-level representation of Feynman integrals, which is based on the Loop-Tree Duality (LTD). We explore the behaviour of the multi-loop iterated residues and explicitly show, by developing a general compact and elegant proof, that contributions associated to displaced poles are cancelled out. The remaining residues, called nested residues as originally introduced in ref. [1], encode the relevant physical information and are naturally mapped onto physical configurations associated to nondisjoint on-shell states. By going further on the mathematical structure of the nested residues, we prove that unphysical singularities vanish, and show how the final expressions can be written by using only causal denominators. In this way, we provide a mathematical proof for the all-loop formulae presented in ref. [2].
Address [Jesus Aguilera-Verdugo, J.; Rodrigo, German; Sborlini, German F. R.; Torres Bobadilla, William J.] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient, E-46980 Valencia, Spain, Email: jesus.aguilera@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000620526300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4726
Permanent link to this record
 

 
Author (up) de Florian, D.; Sassot, R.; Epele, M.; Hernandez-Pinto, R.J.; Stratmann, M.
Title Parton-to-pion fragmentation reloaded Type Journal Article
Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 91 Issue 1 Pages 014035 - 17pp
Keywords
Abstract We present a new, comprehensive global analysis of parton-to-pion fragmentation functions at next-to-leading-order accuracy in QCD. The obtained results are based on the latest experimental information on single-inclusive pion production in electron-positron annihilation, lepton-nucleon deep-inelastic scattering, and proton-proton collisions. An excellent description of all data sets is achieved, and the remaining uncertainties in parton-to-pion fragmentation functions are estimated based on the Hessian method. Extensive comparisons to the results from our previous global analysis are performed.
Address [de Florian, Daniel; Sassot, R.; Hernandez-Pinto, Roger J.] Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis, RA-1428 Buenos Aires, DF, Argentina, Email: deflo@df.uba.ar;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000348679000002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2110
Permanent link to this record