Hi Jim,
Very helpful, thanks.
Barycentric coordinates are an interesting adjunct to your, as I understand, proposed mass-centric coordinate system. FYI, not all mass is spherically configured, i.e., condensing clouds of gas and/or dust and, especially at larger scales where innumerable discrete objects of mass are aggregated.
But I'm thinking more of a point in space between two objects of mass where a small body would be equally accelerated in opposing directions. I can't explain this expectation in the context of any theory, but I think there is such a location, although the differential effects may not be very stable. A nudge towards either object of mass would result in the small body being continuously accelerated in the direction of that object.
I have read that there are strong similarities between GR gravitation and fluid dynamics. I'm a relatively simple person who primarily thinks in conceptual terms. As such, I think that ascribing physical actions to dimensional effects is unrealistic. While, as you explain so well, GR very precisely describes the effects of gravitation through an abstract system of dimensional coordinates, as I understand it attributes the cause of those effects to some undescribed property of spacetime.
Perhaps I'm too naive, but I must insist that the effects of gravitation must be the product of some physical process or mechanism acting on physical elements. I am not harping back tho the idea of a material medium (ether) once proposed to have been required for EM wave propagation.
I suggest that spacetime may contain vacuum energy that is manifested in the appearance of virtual particles in space. I envision that this kinetic energy contained within space (with time being an aspect of this energy) is condensed by interaction with the (aggregated) potential mass-energy of matter.
This should be testable by observing the annihilation rate of virtual particles and antiparticles near and far from significantly massive objects - the virtual particle annihilation rate should vary as a function of gravitational field strength (or vice versa).
In this conception, it is the density gradient of vacuum energy in space that produces the directional accelerating effect of gravitation. Gravity is not only equivalent to acceleration, it IS acceleration produced by the interaction between the potential mass-energy of localized matter and the kinetic energy of space. It also is that accelerating energy that produces temporal effects.
Sorry for going off on this tangent, but I cannot accept the idea that actions could be caused caused by dimensional effects - I can accept dimensional changes produced by physical actions...
Thanks again for your help and consideration!
Jim Dwyer