Consider 2 lifts ,one on ground and other on acceleration, principle of equivalance says you can't find you are on a gravitational field, or accelerating. g decrease when r increase so I can find which lift on gravitational field ?
Because the lift is a small region and the equivalence principle applies approximately. Calculate the different (Newtonian) accelerations at the bottom and top of a typical lift. Could you detect that difference?If it is a point then how lift experiment could possible,