Okay Earth and our entire galaxy is moving through the universe at some unknown high speed, if we went back in time how would we know we are gonna land in the correct space on Earth if its moved.
However if we are going back in time are we going back in time through the universe as we shall see the universe as it was say 40years ago?
Going on them lines the power required to create such a rift would likely be enough to make man able to travel to the stars, as if you can rip the space/time continuem apart to go back in time then likely you can rip it to move through it forward to a distance keeping the time/space similar, because as Einstien said so I believe ( need to research this bit ) That at the speed of light time stands still so it would bring a new era of space travel and time travel.
Sorry for mindless drivel space travel is something I am getting big on
