These concepts, 200 years ago, would have been regarded with the same vigorous skepticism and outright
disbelief as the notion of time travel has presently.
If you recognize that time travel is only a few more technological advancements away, ponder this:
If the ability to time travel is in our future, why aren't you, or your children, or your grandchildren, coming back
to visit you NOW?
Ponder this...it may hold some clues.....