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What is the basic premise of general relativity? It just might be general covariance even if the content of that phrase is controversial. For example: Einstein offered the principle of general covariance as the fundamental physical principle of his general theory of relativity and as responsible for extending the principle of relativity to ...

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The basic premise behind general relativity is the equivalence principle, the idea that an object moving in an accelerating (non-inertial) reference frame is indistinguishable from one moving under the influence of a gravitational field. (As an aside, Einstein's original proofs of time dilation, length contraction, even $E=mc^2$ don't involve any calculus - ...

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Remarkably, it is the case that as long as one is freely falling in a uniform gravitational field, one cannot "feel" the difference between an arbitrarily strong field and an arbitrarily weak one; one "feels" weightless in any case. However, in reality, there are tidal forces (no uniform gravitational fields) which, for extended bodies, tend to stretch one ...

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The sensation with respect to gravity will be almost identical, to be precise: undetectable by your body. While freely falling (in an earth orbit or towards some other body in deep space) only the gravitational tidal forces could be sensed and these vanish quickly (even faster than the square law) with distance from the planet or other body. Can you feel ...

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They should feel the same. You only feel forces in orbit if there is something causing sensations, and nothing does in either case. Even on earth, you don't feel the "force" of gravity; you feel the force of the floor pushing you up so that you don't start falling under gravity's influence. In orbit, there is no floor, so you don't feel gravity. You ...

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