I'm no expert, but I don't think you've got two equivalent experiments there. Imagine two spacecraft, one that is accelerating in intergalactic space, and anot

I'm no expert, but I don't think you've got two equivalent experiments there. Imagine two spacecraft, one that is accelerating in intergalactic space, and another that is spiralling into a black hole, and is in fact already inside the event horizon. In both cases, a beam of light from outside the craft passes into one window and out another on the opposite side. The passengers of both craft can measure the path of the beam, and both discover that the beam is slightly bent. The amount of bending is the same in both cases, even though one is in a gravitational field and the other is accelerating under its own power. The degree of bending is proportional to the strength of that field and to the amount of acceleration, and neither passenger can tell from this experiment which circumstance they are in. There are, of course, some differences. Inside the black hole, all paths end at the singularity. This means that the light beam is spiralling in towards the singularity just like the spacecraft, but at a different angle. Pretty neat, but the passenger on the ship can't tell that this is happening, because they can't catch up with the beam.