Abstract

The Pound-Rebka experiment is often presented as an experimental proof of the Equivalence Principle. However, careful examination of this experiment reveals five different ways that its results can be interpreted. While all are compatible with the Equivalence Principle. each offers a distinct view of both gravity and the nature of the photons being measured. As a result, the Equivalence Principle has a different meaning and definition fur each interpretation. After each of these five possibilities has been presented, the listeners will be asked the following questions for discussion. Does anyone have a different explanation of this experiment? Which Equivalence Principle do you believe in? Since only one of these explanations can be correct, does anyone know of an experimental method by which one of these could be shown to be superior over the others and thus established as the true reality?