Purple dosn't beleve in relativity

I've studied Special Relativity although it was quite a long time ago.The fundamental problem with your post is that Special Relativity only applies in inertial reference frames (i.e. with no acceleration) - it's "Special" because it deals with that "special case".So your version of the "twins paradox" runs into trouble because acceleration is involved. John accelerates to 0.6c on the way out and decelerates to match velocities with Hunter.

Just as Newtonian mechanics is an adequate approximation for Special Relativity when speeds are low enough then surely Special Relativity can be an adequate approximation for General Relativity if the accelerations are low enough.

Sorry, but Newtonian mechanics is still taught in schools. A sufficiently good approximation is fine - even if it isn't entirely correct. And there's nothing I know of that says that a good approximation is unscientific (indeed without infinite accuracy on measurements we can't know that any quantitative theory is anything more than an approximation).

Newtonian mechanics can only work EXACTLY if all objects are stationary relative to each other. If there is ANY relative movement at all Special Relativity gives more accurate results.The REASON Newtonian mechanics works is because it is a very close approximation unless the relative speed is an appreciable fraction of c.I'm sorry but if you don't get that then I'm afraid that you have no business trying to critique General Relativity.

What I'm saying is that if you don't realise the limits of sciences ability to test theories - and if as a result you make unreasonable demands for "proof" of theories you disagree with you are wasting everyones time.And Newtonian mechanics isn't completely wrong - far from it. It's every bit as good as we need for most applications on Earth. Thats why it is still taught - very few people will go into particle physics or astrophysics where they need Relativity. Special Relativity is even more accurate and General Relativity is better still.

Ever heard of the Heisenberg Uncertainty Principle ?The more accurately you know a particle's position the less accurately you can know its momentum. And vice versa.And then theres the problem that we can' measure anything with infinite precision. So even if there were an exact theory which described everything we could never know if we had it or not.And this tangent isn't a waste of your time - you should be learnimg from it. It just would have been better if you actually had found out about it for yourself.