Time travel in my current perception to me is more like elevators. An elevator going Vertical is more like Time travel from past and future, wheres as an elevator going up and down or more of dimensional shifting. Of course there is much more involved but that is just my perception for now. I started to study this on the simplest terms. I seem to be interested more on how things work in theory and I am no longer feel as if I need to just walk into a plasma field and end up somewhere in the past and or future. If I went back to the 1800's and told someone I could travel from New York to Los Angeles in 4 days I would have been burned me at the stake, think about it.