We review the role of the momentum of the electromagnetic (EM) fields
P
e in several areas of modern physics.
P
e represents the EM interaction in equations for matter and light waves propagation. As an application of wave propagation
properties, a first order optical experiment which tests the speed of light in moving rarefied gases is presented. Within
a classical context, the momentum
P
e appears also in proposed tests of EM interactions involving open currents and angular momentum conservation laws.
Moreover, P
e is the link to the unitary vision of the quantum effects of the Aharonov-Bohm (AB) type and, for several of these effects,
the strength of P
e is evaluated. These effects provide a quantum approach to evaluate the limit of the photon mass m
ph. A new effect of the AB type, together with the scalar AB effect, provides the basis for table-top experiments which yield
the limit m
ph = 9.4 × 10−52g, a value that improves the results achieved with recent classical and quantum approaches.
Keywords electromagnetic momentum - Aharonov-Bohm effect - magnetic model of light - Rowland experiment - photon mass
PACS numbers 03.30.+p - 03.65.Ta - 01.55.+b - 42.15.-i