  In Einstein's general relativity, geometry replaces the concept of force in
the description of the gravitation interaction. Such an approach rests on the
universality of free-fall--the weak equivalence principle--and would break down
without it. On the other hand, the teleparallel version of general relativity,
a gauge theory for the translation group, describes the gravitational
interaction by a force similar to the Lorentz force of electromagnetism, a
non-universal interaction. It is shown that, similarly to the Maxwell's
description of electromagnetism, the teleparallel gauge approach provides a
consistent theory for gravitation even in the absence of the weak equivalence
principle.
