someones got to invent it first...as soon as we do,
all the future folks will start visiting us.....
they can't do it until we do it! Get it????
This is real easy...
My guess, is that what is gonna change is the understanding
of physics will progress so that most of the suppositions we
have now will be proven to be impossible, and only a few
will be provable, and/or doable. (just a guess, however!)
So no flames from the past, present or future please.
If they can’t cure the common cold, they certainly can’t invent a way to time travel.