In a neutron interferometer experiment which can successfully demonstrate a quantitative fringe shift due to the different gravitational potential for the neutron in the two legs of the apparatus, an adjunctive consideration must be the nonzero angular velocity of Earth and the lab. As in the classic Michelson-Gale-Pearson experiment done with light, and offset in the fringe pattern is predicted. Such a shift may not be subliminal at present precision levels.

• Received 16 June 1975

DOI:https://doi.org/10.1103/PhysRevLett.35.543