[mad aetherist (OP)]

Einstein reckoned that the speed of light in vacuum was slowed by the gravitational field near mass. But he reckoned that light had to accord with his principle that the speed of light appeared constant. So he invented spacetime. The time in spacetime is the slowing of ticking near mass. The space in spacetime is the shrinking of distance in the radial direction near mass. Spacetime doesnt affect the speed of light, it is the gravitational field that reduces c to say c' measured tangentially to the mass, & further reduces c' to say c" measured radially to the mass, each-both reductions needing an application of gamma.
But the time in spacetime affects an observer's measurement of the speed of light because Einstein says that time is reduced by gamma, where the V in gamma is the speed of the observer if the observer fell to that location from infinity (ie V is the escape velocity of the observer).  And the space in spacetime shrinks the observer's metre-rod by gamma.  Einstein reckons that the four gammas offset exactly resulting in an observer being tricked into seeing a constant c (in vacuum), even tho the real c in vacuum varies (due to the nearness of mass).
Thats my summary of what i have read re Einstein's reckoning.  He needed spacetime in his general theory to explain the apparent constant speed of light in vacuum in his special theory.

Re the bending of light passing mass, Einstein (or was it someone else) said that light did not bend, light always goes straight – he said it was spacetime that bent (due to the nearness of mass), tricking observers into seeing a bending.  I don’t know whether all Einsteinians  agree.

I suspect that Einsteinians don’t agree on much of this, & u can expect to read various versions of their silly spacetime theories.

However i think that we can accept that light does indeed slow near mass (eg Shapiro Delay).  The slowing is due to photaeno drag (which i explained in another thread).

Re light bending near mass i dont accept that light goes straight & that spacetime bends & that we are tricked into thinking that light bends -- i reckon that spacetime does not exist, it is light that bends -- the bending having two causes, (1) an aetheric cause involving the flow of aether into mass, plus (2) a contribution due to photaeno drag.

The non-constant value of c kmps in vacuum is largely ignored. I think that there is a danger that the modern definitions of metre & kilogram & second etc are flawed -- but praps the trickery of gamma exactly overcomes the real variations & our modern definitions are ok.
Actually, it aint just gamma, photaeno drag is not directly involved in gamma, hencely variations in photaeno drag (tween one location & another) must affect m-kg-sec, hencely we have a problem (our standard standards aint standard). 

[Bored chemist]

I suspect that Einsteinians don’t agree on much of this, & u can expect to read various versions of their silly spacetime theories.

They might just say "you are mistaken"
and leave it at that.

[mad aetherist (OP)]

I suspect that Einsteinians don’t agree on much of this, & u can expect to read various versions of their silly spacetime theories.

They might just say "you are mistaken" and leave it at that.

SR & GR & spacetime etc are so complicated & so badly defined & so badly derived that few Einsteinians would agree about much of it. In other words few understand it. Einstein didnt understand it -- he changed it say 30 times before he died, & everyone else changed it hundreds of times during & after. Anyhow my version of spacetime is simply what i remember of what has been written. Any corrections are welcome. I dont believe in spacetime but i am always happy to learn about the theory. The version that i mentioned is i think the smartest (probly from several authors)(cant remember).