Ask Lemmy

Depends on which model of time travel you subscribe to.

If you're working under "Back to the Future" logic, then the best way is to not use time travel at all. Butterfly effect and all that.

If you're working under "Avengers: Endgame" logic where you're actually in an alternate reality, then you could muck around a bit without destroying your own "present" though you would be meddling with the destiny of that parallel universe (assuming you subscribe to the Prime Directive, that would be a bad thing).

You can't change the future (...of your original universe)

That die had already been cast, that wave function had already collapsed. The very act of traveling backwards immediately creates a new timeline no matter what.

Any change you make any step you take, is all affecting that new universe while your original universe keeps on keeping on the way that it was, except now without you in it.

So from your perspective, if you were to travel forward again, things would be different, yes. But only because you're no longer in your original universe. The people in your original universe would see no changes because in that universe, the wave function had already collapsed, the die had already been cast.

There is no chance to EVER get back to your original timeline no matter what. Every jump backwards instantly creates a new universe (one in which the wave function collapses to reveal that you have traveled through time) and every jump forward is in THAT new timeline.

Essentially, you can't go home again.

Well I travelled back in time and killed Hans-Johann Scherzlgruber-Vötzfenstein so the world wouldn't have to suffer through his atrocities.

Go outside the cabin, jerk off, go back.

Go back in time and meet Jesus while He was here on earth

Literally impossible to answer without discussing what type of time travel you mean.

Regardless, the cop out answer is that the time travel you do by existing is the least impactful. You are currently traveling forward through time merely by existing.