madman,

Your analysis of the twin paradox is much too complex. All you need is two twins with synchronized watches. One twin remains home while the other leaves. When the other twin returns they compare watches and the twin who was away finds that his watch has lost time. In the many variations on the theme, acceleration is the one thing that breaks the symmetry. The twin who left home experienced a greater amount of acceleration than the twin who remained behind. He may have traveled to Alpha Centari and back or he may have been in the next room sitting next to a black hole. In one case the acceleration is inertial and in the other it is gravitational but acceleration is acceleration (Einstein’s equivalency principle) and acceleration slows time.