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Your links always hurt my head, Yor_on. What the equivalence principle basically says is that any experiment you perform in a freely falling reference frame is identical to being in an inertial reference frame in deep space (i.e. one that's moving at a constant velocity). This could also be stated that space-time is curved, but tiny patches of it look flat if you're free-falling. I think the point they're making about the time scale "stretching" is something like this: From your vantage point in deep space, you measure your geodesic to the earth and say "from here, it would take me 10 time steps to reach the earth if I were moving at a constant speed (in an inertial reference frame)." Then you start free falling. After falling 1 time step, you look down and say "Oh my goodness, my clock has changed! What was 1 time step worth of distance has stretched to 2 time steps worth!" Etc. I think "stretching" in this sense means that each "tick" is worth more distance along your path as you get closer to the earth. I'm not sure if that's clear. It's starting to make sense to me, but I don't think I understand it well enough to really explain it any clearer than mud...
I read this but I'm not sure of how to understand it?"Objects in free-fall really do not accelerate, but rather the closer they get to an object such as the Earth, the more the time scale becomes stretched due to spacetime distortion around the planetary object (this is gravity). An object in free-fall is in actuality inertial, but as it approaches the planetary object the time scale stretches at an accelerated rate, giving the appearance that it is accelerating towards the planetary object when, in fact, the falling body really isn't accelerating at all. This is why an accelerometer in free-fall doesn't register any acceleration; there isn't any." From Equivalence principle
(But the fluid have to get very hot I guess as the rotational pressure builds up?