Stephen King’s Rules for Time Travel

Here is a Wired interview with Stephen King about the mechanics of time travel.  They cover: "the grandfather paradox, and the scariest thing about trying to change history."  The grandfather paradox is the question: What if you went back in time and killed your own grandfather?  They also discuss the "butterfly effect" which is dealt with in detail in the novel.

Here's a clip from their discussion of the "reset" idea:
King: The idea of the reset was one of the more interesting things about the book to me. You can get the idea from computers, where you can delete all this material and start over again and it never even leaves a mark. You just highlight everything, bop Delete, and it’s gone.

Wired: Well, on a computer you think it’s gone, but it’s actually not.

King: It’s like in the story. They think it’s a complete reset, but the guardian tells Jake that it really isn’t. It looked that way to you, but that stuff was still there.