I see no purpose to the referent field other than to have it be the three dimensional geometry in which particles with motion are interacting. Apparently, gravitons behave like extremely small "bullets" which interact with one another by direct collision.
Tom Van Flandern made the case for a light carrying medium - based on the simple fact that a wave is a geometrical form of momentum that must occur within a medium. Otherwise, it does not exist. It does appear that the electromagnetic wave does not behave the same as a compression wave in a vapor - i.e. sound. If we knew the nature of an Elyson, this behavior would be explainable.
Proton matter appears to have two fundamental characteristics: they are literally in the way - an obstacle - and they bind together to make structures.
When anyone proposes a phenomena or entity, it has no meaning or utility unless it can be observed, measured, tested. Otherwise a proposed entity is deuces wild.
An idea or theory must be testable in order to have any value.
Gregg Wilson