The Grandfather Paradox

It's only potential in the sense that it doesn't say which events are really cause are related with each other. And so unfortunately, for Orson Scott Card, Enders game doesn't work. You cannot use the EPR to transfer any information. So there is no violation of causality. In this sense, quantum mechanics with all its weird stuff and panglement randomness is not at all with relative heat, with the causal structure.