In this mock-up universe there exists two observers on a large disc of great mass, and there is a third observer a great distance away. In this scenario we take the observation of the spinning disc from the distant (third) observer. I was thinking about Special Relativity and Mach's Principle and I thought about an enormous spinning rigid disk, one that spun such that it rotated at such that the edge of the disc approached .999999c or something like that. I was thinking about the implications of Mach's principle when applied to for this large rigid, isolated disc. According to whatever observers are on the disc, they would not observe each other to be moving at all, they are at rest to all other observers on the disc. Yet if a distant observer were to look at this disc from a great distance. The observer would see that the edge of the disc is not rigid, it would appear to warping. - because the edge of the disc could not travel faster than the speed of light. Which it would if the speed of the outside part of the disc is 2pi times the rate of rotation. This would appear to me to be some kind of contradiction, because the outside observer would be influenced by the inside observer as if the disc were not warped and the observer observing the thing on the outer part of the disc would see both the warpage, and observe the acted influence as if the disc were not warped. I am pretty confident so far, but then I started to think of something that I am a bit less sure of. I thought that maybe that wasn't possible, I thought that the centripetal force would be so great that the outer observers would detach themselves from the disc before the contradiction ever occurred - because it would simply have to. Then I thought that because of Mach's principle the centripetal force of the distant observer should be reflexive of that centripetal force. - I think this is a stretch - but it's as if the distant observer is also spinning around the center - because the true motion of rotation is relative - so that distant observer would experience a centripetal force as well. So then I thought that maybe the interaction of galaxies could be like that - that expansion may be correlated with the sum distribution of all centrifuges.