Astrophysical invariance of the fine-structure constant: observation and theory

A theoretical result based on nonlinear quantum electrodynamics could suggest the invariance of the fine-structure constant everywhere in the Universe and at any epochs of its history. The present paper updates while summarizing this theoretical framework, and provides a critical survey of recent astrophysical observations related to this constant’s value. We conclude that, from an observational point of view, this constant could indeed be invariant over cosmic space and epochs, in line with the theoretical study.