Your statement agrees that the subject is changed, whatever be the reason.
I don't think the subject aka the observer has changed at all, in any sense that matters for noticing that the gravity of the sun bends the light from distant stars. If by 'subject' you mean 'medium' then yes, mass seems to 'change' or warp it.
I speculated, there must be a pre-set status quo, else the to and fro actions which cause the waves would not occur.
I assume you refer to some kind of 'aether'? You should probably go back to
Message 8 to begin reading the discussion as to how this fits in with modern physics.
A stream of water heads for the sea - but this is driven by terrain and impacting forces.
To be pedantic it is driven by gravity, but its exact path is determined by also by geographical considerations.
In space, to determine the force of gravity in its pristine form, one must eliminate all debris in space.
I'm not sure you are barking up the right tree here, and I don't think your experiment is technically possible. I'm not sure there is some kind of Platonic Gravity that we can track down. Do you need to determine the force gravity in a massless universe? In modern physics it kind of sounds like you just want to calculate the shape of a universe with no mass in it - it might be interesting, but what would this tell us about gravity or why light bends as it passes near objects of high mass (such as the sun).
IOW, would there be gravity in space without space bodies?
This could be a philosophical question. As a scientific question, I'm not sure what the answer would be - and I assume by 'space bodies' you refer to anything that has mass, including WIMPS, should the promising new discoveries be verified. I think the answer would be 'no' but that would only be on the assumption we were talking about bog-standard gravity which is a force that occurs for some reason between two masses. Do you have a better reason than the curvature of space proposed by Einstein? That
was the original question I asked...