Towards gauge theories in four dimensions

• Published in: The journal of high energy physics Vol. 2016; no. 2; pp. 1 - 14
• Main Authors: Hernández-Pinto, Roger J., Sborlini, Germán F. R., Rodrigo, Germán
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2016
• Subjects: Cancellation; Classical and Quantum Gravitation; Elementary Particles; Emission; Gauge theory; Infrared; Mathematical analysis; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; Singularities; String Theory; Subtraction; Theorem proving; NLO Computations
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP02(2016)044

A bstract The abundance of infrared singularities in gauge theories due to unresolved emission of massless particles (soft and collinear) represents the main difficulty in perturbative calculations. They are typically regularized in dimensional regularization, and their subtraction is usually achieved independently for virtual and real corrections. In this paper, we introduce a new method based on the loop-tree duality (LTD) theorem to accomplish the summation over degenerate infrared states directly at the integrand level such that the cancellation of the infrared divergences is achieved simultaneously, and apply it to reference examples as a proof of concept. Ultraviolet divergences, which are the consequence of the point-like nature of the theory, are also reinterpreted physically in this framework. The proposed method opens the intriguing possibility of carrying out purely four-dimensional implementations of higher-order perturbative calculations at next-to-leading order (NLO) and beyond free of soft and final-state collinear subtractions.