: : : : : A Quasar is 60 billion light years away. Right now : : : : on that quasar the are watching us enter the Cenozoic : : : : era. If they had a device to see well enough than : : : : they could watch us right this second 60 billion : : : : years ago. If someday it is possible to travel many : : : : many many light years we might be able to view earth : : : : as it was a long time ago. Is this somewhat right?

: : : Do yo mean 60 Million light-years?

: : : John

: : : Actually, 60 M sounds right, but that places us in the Cretaceous period of the Dinosaurs. If you pack up right now and travel at NON-RELATIVISTIC speeds away from earth, and you live long enough to get to X-million LY from earth, your vision of earth from that distance would be as it was X-million Years ago. After all, when you are stationary, light from anywhere travels to reach you at a given velocity, and you will see light from that source as it appeared years ago according to your distance from that object. This is not the same as time travel, however, and a million years to you will seem like a million years to your friends back on earth, as long as you don't approach light speed. Once you approach light-speed, time dilation takes over and aging slows...but this is still not the same as time travel. Time marches inexorably forward, and only slows down when relativity says so.

: To me time does not exist, the thing that we call time is simply the memories and traces that we leave behind. There are only moments, each moment that passes by is part of the "time" that we gather in our minds. According to this time-travel is impossible. If there ever will be time-travel (EVER) then it will have already been present because of visiting people from the future. Time travel to the future is impossible because, for ex., if I went back and killed my grandfather then would I simply disappear (violating the first law of thermodynamics, I think)..Please respond.. I am only 15 and don't really get to discuss these sorts of issues..

Actually, time must exist. This is evident of a couple experiments done involving the theory of relativity. And travel back in time might also indeed be possible through a wormhole. For example, if one could sustain a wormhole open at a size in which he could travel through, manipulation of the speed of one of the gates of the wormhole could allow for one opening of the wormhole to be at a different point in time than the other point. The reasoning for this suggests that you could not go back and kill your grandfather because you could not travel back in time before the orrignal manipulation of the wormhole. There is also another theory that suggests that if you could travel back in time to interrupt past events, there would always exist a scenario in which all changed events would react to exiting events in a way so to cancel out the changed event and that scenario would always occur.