Genuine Dyons in Born-Infeld Electrodynamics

Abstract

Study of magnetic monopoles in the original version of Born-Infeld (BI) electrodynamics is performed. It then is realized that interesting new physics emerge and they include exotic behavior of radial electric monopole field such as its regularity as $r\to 0$ and its changing behavior with the absence or presence of the radial magnetic monopole field. This last point has been interpreted as the manifestation of the existence of point-like dyons in abelian BI theory. Two pieces of clear evidences in favor of this dyon interpretation are provided. It is also demonstrated that despite these unique features having no analogues in standard Maxwell theory, the cherished Dirac quantisation condition remains unchanged. Lastly, comments are given concerning that dyons found here in the original version of BI electrodynamics should be distinguished from the ones with the same name or BIons being studied in the recent literature on D-brane physics.