Comments by "p11" (@porky1118) on "Trope Talk: Time Travel" video.

There's only one time travel system, that makes sense: Travelling back in time creates a new timeline. Everything done in the past, will have consequences in the future. But you could timetravel back and forth between two alternate timelines without creating a new one, as long as you never travel to a point in time, which is in the past of a time in this timeline you already visited. It would also be allowed, when the timeline you come from is deleted. But this would not mean, that if you kill your father, you will disappear as well.
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