[HappMacDonald]

Per relativity, any medium that could conceptually facilitate transfer of information or of causality (which are basically the same thing) faster than the speed that light happens to travel at would also be able to reverse direction and arrive at their source in space earlier than the time that they left. That effect is completely unrelated to light itself.

[bookofjoe]

"If time travel is possible, then there is no such thing as time." — Kurt Gödel, Einstein's great friend at Princeton's Institute For Advanced Study.

Einstein once remarked that he went to his office "just to have the privilege of walking home with Kurt Gödel."

https://imgur.com/a/avUwwHk

https://archive.ph/6doQh#selection-707.279-711.1

https://www.amazon.com/When-Einstein-Walked-G%C3%B6del-Excur...