  There have been various claims that the Equivalence Principle, as originally
formulated by Einstein, presents several difficulties when extended to the
quantum domain, even in the regime of weak gravity. Here we point out that by
following the same approach as used for other classical principles, e.g. the
principle of conservation of energy, one can, for weak fields, obtain a
straightforward quantum formulation of the principle. We draw attention to a
recently performed test that confirms the Equivalence Principle in this form
and discuss its implications.
