I am writing a novel about time travel and don't quite understand the theoretical science behind it. If I understand correctly, Einstein's General Relativity theory opened up the door for the possibility of time travel even though he dismissed the idea as impractical. Einstein proved that time and space were linked as one and called this the Space Time Continum. And this Space Time Continum is curved not straight allowing for the possibility of a closed loop being created and being referred to as a CTC or a Closed Timelike Curve. What I would like explained is how theoretical time travel is accomplished along this CTC. Does the time traveler have to be traveling in space and at a certain speed along the CTC. Is it by pure chance that he even finds the CTC to allow for his time travel. Would he have to be traveling at the speed of light or close to this maximum universal speed. Does he have to enter a worm hole that connects two distant points along the CTC or could he just fly along the CTC and eventually lap his own lifeline winding up in his past. If you could explain this in the simplest terms possible I would greatly appreciate it.