[Red Badger]

Yes, every atom of your body existed a billion years ago, just somewhere else. If you travel back or forward in time, you would essentially be ‘creating’ mass that did not exist previously in that universe, which is a no-no..............

[Cboldt]

Well, except that time is relative, and that what we think of as "time travel" actually does take place. See twins paradox, played out on much smaller time variation with GPS system.

Everything is going forward in time though.

I do agree with you that the "replicator" aspect is forbidden. Still made for a good story.