On the conventionality of simultaneity in special relativity

In this paper the classical topic of "conventionality" in defining the simultaneity (or synchrony) of distant events is tackled again, and the validity of Reichenbach's view is carefully circumscribed. In particular, the role of "one-way" assumptions in the foundations of special relativity is emphasized. The restriction by the round-trip isotropy condition Oil the admissible distance functions in inertial frames is studied, mad its relevance to several is-sues (absolute simultaneity, the interpretation of Michelson-Morley type experiments, the self-measured,speed of et clock) is shown. Two "clock transport" synchronizations in an inertial frame, using self-measured,speed and "proper distance," are presented in detail, and the agreement of the synchronies so established with standard synchrony is proven to be noncircular. By assuming a reasonable concept of "convention" this result is shown to dissolve several objections by supporters of a,strong version of conventionalism. Throughout, a number of common misapprehensions in the literature are pointed out.