  The effects of a nonzero photon rest mass can be incorporated into
electromagnetism in a simple way using the Proca equations. In this vein, two
interesting implications regarding the possible existence of a massive photon
in nature, i.e., tiny alterations in the known values of both the anomalous
magnetic moment of the electron and the gravitational deflection of
electromagnetic radiation, are utilized to set upper limits on its mass. The
bounds obtained are not as stringent as those recently found; nonetheless, they
are comparable to other existing bounds and bring new elements to the issue of
restricting the photon mass.
