I'm certain that the following thoughts cannot be original, but I'll write them anyway.
I've always wanted to travel back in time; I think most people have thought about it. As an interesting sidenote, ask someone how they would adapt to the new time period if they go back in time without mentioning when. When I think of this question, I immediately think about the Roman era, where my professor had thought about the 13th century. I'm sure a psychiatrist could make some sense out of it.
But I feel reasonably confident that time travel is not possible, and I make the argument excluding the 'arrow of time' (entropy, fundamental disorder of the universe caused mostly by heat transfer energy loss). Here's the simple case:
Let's say you have a can of Green Giant green beans sitting on a table for twenty minutes. You then take that can of green beans back in time ten minutes and set it on the table next to the beans that are already there. What's wrong with this picture? The same atoms (and hence subatomic particles, etc) are in two different places at the sme time. Basically, continuity (in the chemical engineering sense) is violated because the same mass is in two different places at the same time. Same problems for future travel (although special relativity could make this happen if you had a fast enough spaceship).
Theoretically, continuity violation is not possible. Even considering nuclear physics, both mass and energy have to be conserved. So unless there is some phenomenon with which I am not familiar (and there are many), I am ruling out time travel as a potential area for future study in my lifetime.
I will still enjoy the movies though.
By the way, if someone wants to use the sound barrier as a reason not to exclude time travel research, understand that the physical laws in discussion are a little more rigid than the mechanical engineering problem of supersonic travel.
Farewell Reader, have a good day.
Hussman
