Conformal correlators as simplex integrals in momentum space

Abstract We find the general solution of the conformal Ward identities for scalar n-point functions in momentum space and in general dimension. The solution is given in terms of integrals over (n − 1)-simplices in momentum space. The n operators are inserted at the n vertices of the simplex, and the...

Full description

Bibliographic Details
Main Authors: Adam Bzowski, Paul McFadden, Kostas Skenderis
Format: Article
Language:English
Published: SpringerOpen 2021-01-01
Series:Journal of High Energy Physics
Subjects:
Online Access:https://doi.org/10.1007/JHEP01(2021)192
_version_ 1818877792556679168
author Adam Bzowski
Paul McFadden
Kostas Skenderis
author_facet Adam Bzowski
Paul McFadden
Kostas Skenderis
author_sort Adam Bzowski
collection DOAJ
description Abstract We find the general solution of the conformal Ward identities for scalar n-point functions in momentum space and in general dimension. The solution is given in terms of integrals over (n − 1)-simplices in momentum space. The n operators are inserted at the n vertices of the simplex, and the momenta running between any two vertices of the simplex are the integration variables. The integrand involves an arbitrary function of momentum-space cross ratios constructed from the integration variables, while the external momenta enter only via momentum conservation at each vertex. Correlators where the function of cross ratios is a monomial exhibit a remarkable recursive structure where n-point functions are built in terms of (n − 1)-point functions. To illustrate our discussion, we derive the simplex representation of n-point contact Witten diagrams in a holographic conformal field theory. This can be achieved through both a recursive method, as well as an approach based on the star-mesh transformation of electrical circuit theory. The resulting expression for the function of cross ratios involves (n − 2) integrations, which is an improvement (when n > 4) relative to the Mellin representation that involves n(n − 3)/2 integrations.
first_indexed 2024-12-19T14:03:55Z
format Article
id doaj.art-c9b9e1409f55405a82df8c87442942ca
institution Directory Open Access Journal
issn 1029-8479
language English
last_indexed 2024-12-19T14:03:55Z
publishDate 2021-01-01
publisher SpringerOpen
record_format Article
series Journal of High Energy Physics
spelling doaj.art-c9b9e1409f55405a82df8c87442942ca2022-12-21T20:18:23ZengSpringerOpenJournal of High Energy Physics1029-84792021-01-012021114610.1007/JHEP01(2021)192Conformal correlators as simplex integrals in momentum spaceAdam Bzowski0Paul McFadden1Kostas Skenderis2Department of Physics and Astronomy, Uppsala UniversitySchool of Mathematics, Statistics & Physics, Newcastle UniversitySTAG Research Center & Mathematical Sciences, University of SouthamptonAbstract We find the general solution of the conformal Ward identities for scalar n-point functions in momentum space and in general dimension. The solution is given in terms of integrals over (n − 1)-simplices in momentum space. The n operators are inserted at the n vertices of the simplex, and the momenta running between any two vertices of the simplex are the integration variables. The integrand involves an arbitrary function of momentum-space cross ratios constructed from the integration variables, while the external momenta enter only via momentum conservation at each vertex. Correlators where the function of cross ratios is a monomial exhibit a remarkable recursive structure where n-point functions are built in terms of (n − 1)-point functions. To illustrate our discussion, we derive the simplex representation of n-point contact Witten diagrams in a holographic conformal field theory. This can be achieved through both a recursive method, as well as an approach based on the star-mesh transformation of electrical circuit theory. The resulting expression for the function of cross ratios involves (n − 2) integrations, which is an improvement (when n > 4) relative to the Mellin representation that involves n(n − 3)/2 integrations.https://doi.org/10.1007/JHEP01(2021)192AdS-CFT CorrespondenceConformal and W SymmetryConformal Field Theory
spellingShingle Adam Bzowski
Paul McFadden
Kostas Skenderis
Conformal correlators as simplex integrals in momentum space
Journal of High Energy Physics
AdS-CFT Correspondence
Conformal and W Symmetry
Conformal Field Theory
title Conformal correlators as simplex integrals in momentum space
title_full Conformal correlators as simplex integrals in momentum space
title_fullStr Conformal correlators as simplex integrals in momentum space
title_full_unstemmed Conformal correlators as simplex integrals in momentum space
title_short Conformal correlators as simplex integrals in momentum space
title_sort conformal correlators as simplex integrals in momentum space
topic AdS-CFT Correspondence
Conformal and W Symmetry
Conformal Field Theory
url https://doi.org/10.1007/JHEP01(2021)192
work_keys_str_mv AT adambzowski conformalcorrelatorsassimplexintegralsinmomentumspace
AT paulmcfadden conformalcorrelatorsassimplexintegralsinmomentumspace
AT kostasskenderis conformalcorrelatorsassimplexintegralsinmomentumspace