|>> || >>79293 |
I don't think a time machine as popular conceived would ever be possible, because of certain implications of Everett-interpretation quantum theory. (But I also think that's why the 'grandfather paradox', even Hawking's radiation version of it, aren't the actual reason time travel is impossible; besides, since when did the universe prevent something just because it would have a destructive consequence? There must be another reason.)
So, you go back in time, to an earlier evolution of spacetime that you previously passed through (nvm how you got there.) The picosecond you arrive, your presence will alter the evolution of dynamical systems on a quantum level, which will propagate to the macro level. Like, just the very first atom of your probe or whatever would cause one photon to veer off in a different direction; that's all it would take for you to suddenly be 'off-course' for the world-line you originally left. But it's not like you wouldn't be in a real world that would still continue to evolve from that point in time under natural laws, but nothing you did would ever affect the wordline you came from, just the evolution of the new universe you had arrived in, because you diverged from that reality the second one single fundamental particle began to evolve in a different way
(i.e. the world where you didn't appear back in time -- say, like our world, where no one showed up to Hawking's time traveler party -- is, from an information theoretic perspective, exactly like the world where some future humans do discover time travel and ultimately travel to that time period, but we will never get to that world; those time travelers just left their home universe, to seemingly disappear and be lost forever, those who sent them out wondering why their history books don't miraculously change, while those who receive them at the party wonder how the time travelers, who are now just a normal part of their universe, can continue to exist, since their arrival should surely disrupt the chain of events that leads to their creation? But in reality, they are just hopping between quantum realities, which are eternally separated from one another by whatever force it is that causes the many-worlding of realities.)
Essentially, if the many worlds interpretation is true, the fact that different outcomes of quantum events segregates worldlines from one another means you can never travel to a different time, only to a different reality, even in principle, regardless of whatever exotic means you might propose to actually accomplish the thing.
And, anyway, I don't think that's what OP is really asking, OP is asking about technologies to experience the past without actually going there. So to OP; 100 years from now future tech prediction, full brain immersive simulated environments where individual aspects of brain function can be enhanced or suppressed by program; so boot up life as a medieval peasant and actually become as dumb as a medieval peasant while you're 'playing.'