2019/05/01 by T. Frederico, Dyana C. Duarte, Frederico, Tobias +9
Physics and Astronomy · #Advanced Differential Geometry Research #Cosmology and Gravitation Theories #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.1905.00703
openalex publication_date 2019/05/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The fermion self-energy is calculated from the rainbow-ladder truncation of the Dyson-Schwinger equation (DSE) in quantum electrodynamics (QED) for spacelike momenta and in the complex momentum plane close to the timelike region, both using Pauli-Villars regularization. Specifically, the DSE is solved in the complex momentum plane by rotating either the energy component of the four-momentum or the magnitude of Euclidean four-momentum to reach the timelike region in Minkowski space. The coupling constant is appropriately chosen to ensure the singularities of the fermion propagator are located in the timelike region while producing significant differences from the perturbative solutions. For simplicity, we choose Feynman gauge, but the method is applicable in other covariant gauges as well. We demonstrate that the approximate spectral representation based on the fermion self-energy near the timelike region is consistent with the solution of the DSE directly in the Euclidean space.