[Tyabann]

Originally Posted by cicero

(shameless credit grab) I wrote the haruhi=free will theory on the baka-tsuki forums. Was I the first one to do so? Because if I was, I can feel good about being original...

Yes, that was you.

Originally Posted by Roger Rambo

How exactly does the Novikov theory "prevent" an event from occurring in the past? That's another thing I've always found weird about time travel dealing with paradoxes, is how exactly the universe prevents a paradox from taking place?

There are things that a time traveler could do to prevent the titanic form sinking, or at least change the history of that episode. He could transport of a hundred of his friends all dressed out in futuristic gear on board the titanic, walk up to the captain while exposing himself to the entire crew, and have all his friends sing a musical number about the fate of the Titanic, and when it will happen.

When someone tries to do this, does the universe manifest in the form of Yotsuba, and kick them all in the nades before they can depart to the past?

Maybe it does. In any case, the time traveler would find themselves, through a combination of circumstance, either unable to stop the Titanic's sinking, or be the cause of the Titanic's sinking.

The latter is more likely, in my books.

How this occurs isn't explained by the principle, nor does it need to. For the purposes of fiction, we only need to know that "A wizard did it."

Originally Posted by PastPrime

In "Back to the Future" Time Travel when he returned to his time the Titanic would not have sunk and the Time line would have changed. In "DBZ" Time Travel a new Time Line would be created where the Titanic did not sink, but when he returned to his time nothing would have changed. And, according to Nostradamus, there are many possible futures. His prophesies were just the most likely.
And, for another thing, has the author stated what version of Time travel he is using. I don't think we can go by what Mikuru said since there is evidence that the Time Travelers have affected the Time Line. It is obvious that they can change things, at least through a third party. Otherwise there would be no point in having Kyon do things to restore the Time Line.

What Mikuru says is clearly wrong anyway...

The Haruhi series probably uses the version that avoids the grandfather paradox, i.e. self-consistency.

Restoring the timeline is not the same thing as changing the timeline.