2020/05/31 by Eduardo Casali, Sebastian Mizera, Piotr Tourkine
Physics and Astronomy · Social Sciences · #Black Holes and Theoretical Physics #Duality (order theory) #Feynman diagram #International Science and Diplomacy #Limit (mathematics) #Monodromy #Noncommutative and Quantum Gravity Theories #Perturbation theory (quantum mechanics) #Scattering amplitude #String (physics) #String duality #String field theory #String theory #hep-th
paper · pdf · doi:10.1007/jhep03(2021)048
published as JHEP 2021, 48 (2021) · 26 pages, 15 figures. Figures in IPE (http://ipe.otfried.org/). v2: clarified discussions, added a few references. Published version
openalex created_date 2020/05/21 · openalex publication_date 2021/03/03 · arxiv created 2021/03/07 · arxiv updated 2021/03/09 · openalex updated_date 2026/08/06
A bstract Color-kinematics duality is a remarkable conjectured property of gauge theory which, together with double copy, is at the heart of a wealth of new developments in scattering amplitudes. So far, its validity has been verified in most cases only empirically, with limited ab initio understanding beyond tree-level. In this paper we provide initial steps in a first-principle understanding of color-kinematics duality and double-copy at loop level, through a detailed analysis of the field-theory limit of the monodromy relations of string theory at one loop. In this limit, we dissect the type of Feynman graphs generated and the relations they obey. We find that graphs with contact-terms are unavoidable and are generated in the field theory limit of “bulk” contours which do not have a standard physical interpretation in string perturbation theory. We show how they are related to ambiguities in the definition of the loop momentum and that their role is precisely to cancel those ambiguities.