Oh guys you talk nonsense. I do dabble in time travel at times, so I know :).
(Why I'm here today? I'm particularly fond of this time period; it's the perfect time when humans had enough computing power to do something interesting, but before the whole industry went to shit. Remind me to tell you about the future some other time.)
State machines can be checkpoint at any state, load up whatever time you like, is there time per se?