LIMITS ON NEW FORCES COEXISTING WITH ELECTROMAGNETISM

We consider the limits arising from different electromagnetic systems on the existence of a possible new electromagnetic analogue of the fif th force. Although such a force may have no intrinsic connection to el ectromagnetism (or gravity), its effects could be manifested through v arious anomalies in electromagnetic systems, for appropriate values of the coupling strength and range. Our work generalizes that of Bartlet t and Logl (who considered the case of a massive vector field coexisti ng with massless electrodynamics) to encompass a broad class of phenom enological interactions mediated by both scalar and vector exchanges. By combining data from both gravitational and electromagnetic systems, one can eventually set limits on a new force whose range lambda exten ds from the subatomic scale (lambda almost-equal-to 10(-15) m) to the astrophysical scale (lambda almost-equal-to 10(12) m).