  A detailed distribution of the force of electromagnetic radiation in and
around dielectric media can be obtained by a direct application of the Lorentz
law of force in conjunction with Maxwell's equations. We develop a theory of
the force exerted by a focused light beam on the free surface as well as within
the volume of a transparent dielectric medium. Although the medium can be
either solid or liquid, here we emphasize the application of the formulas to
liquids since, in principle at least, surface deformations and liquid motions
are measurable. Our theory predicts that, upon entering the liquid from the
free space, the beam of light exerts an outward vertical force on the entrance
surface that tends to produce a localized bulge. This surface force, however,
is much weaker than that predicted by prevailing theories and, in contrast to
current beliefs, is found to depend on the polarization state of the incident
beam. Within the volume of the liquid we predict that the forces of radiation
tend to create four counter-rotating vortices at the four corners of the
focused spot; the sense of rotation within these vortices depends on the
direction of the incident polarization. These striking departures from
conventional wisdom with regard to the force of radiation arise from a revision
in the form of the Lorentz law as applied to the bound charges/currents within
a dielectric medium.
