Time only goes forward but never backwards.
We naturally travel into the future. The rate at which we travel can be changed. When you approach the speed of light you are slowed down dramatically. The rest of the universe ticks on at the "normal " rate. When you drop out of your hyper speed it just appears that you jumped forward in time. Its effect is not much different than being cryogenically preserved and then thawed out in a few hundred years (like Buck Rogers). You would wake up in the future.
Traveling back in time however is quite impossible as the past does not exist anymore. You would have to put every particle back in its previous location in space with the same energy level, speed, direction, etc. Even if you could do that it really wouldn't be the past.
We naturally travel into the future. The rate at which we travel can be changed. When you approach the speed of light you are slowed down dramatically. The rest of the universe ticks on at the "normal " rate. When you drop out of your hyper speed it just appears that you jumped forward in time. Its effect is not much different than being cryogenically preserved and then thawed out in a few hundred years (like Buck Rogers). You would wake up in the future.
Traveling back in time however is quite impossible as the past does not exist anymore. You would have to put every particle back in its previous location in space with the same energy level, speed, direction, etc. Even if you could do that it really wouldn't be the past.
