This paper shows how difficult it is for FTL information transfer to fit within the two main theories that currently form the hallmark of modern physics, General Relativity and Quantum Physics. In a nutshell, quantum physics says there must be instantaneous action between two distant points.  This is fine as long as those two points are not moving with respect with each other. But what if those two points are in motion with respect to each other? This is where Einstein's General Theory of Relativity comes into play - if there is relativistic motion (motion comparable to the speed of light) - then your communicators will no longer be in the same frame of reference. The device that is being moved will experience less time than the device that is stationary. This means if the two devices are linked via a FTL conduit, then it would be possible to speak through them into the future or past... but this messes up the reason quantum physics is giving us the ability to link the two communicators in the first place. Quantum Mechanics always wants the connection between your two FTL communicators to be simultaneous (where the time delay between transmission and reception is always zero no matter what), but General Relativity says that since time can be distorted due to motion, simultaneity is no longer guaranteed. This is an example where each theory provides results that say exactly the opposite things. Sheesh.

           How EPR Kindred Methodologies Show Disagreement Between Quantum and Relativity Theories               

Which theory is right? Well, we can make speculations based on what we know about each theory. These are called Gedanken experiments - thought experiments. They come in handy especially when the would be experimenter is too poor to be able to afford to do the experiment for real, or it is just plain impossible to perform any experiment because the tools or means do not exist.  Well, if we can do an experiment where one FTL communicator is kept at home and the other is accelerated close to light speed and then the transmit button is pressed, what will be the outcome? Will the other communicator instantly activate despite the fact they are no longer experiencing time the same way and proving quantum theory is correct, or will the  listening device register a signal before the other communicator transmitted it, demonstrating time-parity non-conservation and proving relativity theory? What do you predict?