@Jaden3 Here is another diagram that I find helpful in understanding #TimeTravel re the speed of light in. It depicts #Spacetime intervals. A cone is positioned on 3D axes. The vertical axis is time, two (for simplicity) horizontal axes are space. The narrowest point of the cone is at the origin; the here and now. #WorldLines inside the cone are called time-like. Outside the cone world lines are space-like. Time travel involves going from time-like to space-like world-lines.