How do parallel timelines and dimensions affect each other?
This is my theory on how something that happens in one timeline affects the other timeline.
Just after Link returns to being a child in OoT, he lefts for Termina. With the Door of Time closed, Ganondorf's attack on Hyrule Castle fails, and it's arrested. A few months after that, when he is about to be executed, he unexplainably obtains the Triforce of Power.
Well, what if that was caused because around that same time, in the other timeline, Ganondorf stole the Triforce of Power? Seems logical, that if the Triforce is nearly as omnipotent and omnipresent as they say, it could break the space-time continum to cross to a dimension that runs parallel.
In the same manner in wich Ganondorf's Triforce of Power in the Child Timeline could have been the result of an event in a timeline that runs parallel; the return of Ganondorf in the Adult Timeline could have been the result of an event in a dimension parallel to Hyrule.
In the Adult Timeline, Link was never able to travel to Termina, because he was sealed inside the Sacred Realm. Termina was destroyed by the Moon in the Adult Timeline.
Could it have been possible, that the impact of the Moon over Termina caused such a great explosion that it not only destroyed Termina and everything around it but eventually, after some years, crossed throught dimensions, seeing that Termina and Hyrule have an extradimensional link, in the manner of "a fell wind"? The impact of the Moon over Termina could have reached Hyrule, but not in the form of an explosive wave, but in the form of a distruptive wave that weakened the seal over Ganondorf, and allowed him to free himself?
Re: How do parallel timelines and dimensions affect each other?
I don't think that there is any way that the two alternate timelines could ever physically cross. They are not bound on any sort of similar physical plane.
Where the idea of the timelines converging DOES get interesting, however, is with the gods. Are there two separate sets of deities in the two different timelines? Or are the gods "above" time and watch over them both?