I saw two enormous UFOs flying along about eight years ago. Say what you want, but it was a clear day, they were ~1500 above me, and I know what I saw. They maneuvered and moved in such a beautifully graceful way it has puzzled me ever since. Finally, I think I may have an explanation. What I saw were two objects which had no weight, and thus no inertia. Anything we are used to seeing moves with inertia and turning or accelerating requires a counteracting force which creates what we call G forces because gravity and inertia are equivalent. A weightless thing would have no inertia and could turn or accelerate without any G force. I think this is why their movement was so graceful and striking. Somehow, I believe these things separate themselves from the inertial field of our space/time and move in their own inertial bubble. This would explain why they can move without creating a sonic boom, how they make radical turns, and how they accelerate instantly.
When Jesus appeared to Thomas in the upper room, He was 'at' the room before He stepped into the room, e.g. He was therre in the upper room but at a higher spatial variable plane, then it is like His shadow appeared to them. Perhaps the three spatial manifestation is the sort of shadow of the four spatial reality og His real glorified body.