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[Marvel Movies] What's the importance of the Aether in Thor 2? (Thor 2 Spoilers)

So Malekith wants to release it when the 9 realms are in convergence, but why would nine planets being aligned be so imporant? I could see the Aether destroying all of those nine realms but why the whole universe? Is it because they're super far apart?
gpt
The Aether doesn't destroy the universe, it returns it to darkness, the Elves' natural habitat. "In the beginning" there was a battle between light and darkness, and the light won out (that's what Bor's battle in  Svartalfheim at the beginning was all about). Many forms of life that could thrive in the light came to power; asgardians, humans, etc. but the Elves, the last of the species that can thrive in darkness, want to return the universe to darkness so that their kind and others like them can live and expand their influence. The problem being that all life that has already evolved to live in the light cannot live in darkness, and will die out.

*That's* that the Aether was all about. The planetary alignment coincides with the metaphysical alignment of the nine "Realms" (or dimensions, or realities, whatever you want to call them) where they're all "closest". That's why various portals were opening up all over the place, and how Jane and Thor are able to travel from Svartalfheim to Earth seemingly instantaneously. Having portals to all the realms easily accessible means Malekith could infect the entire universe with the Aether at once instead of having to go from place and place and giving each's inhabitants time to prepare and fight him.

I suspect the analogies of "light" and "darkness" are actually referring to matter and anti-matter. Scientists believe there were originally slightly unequal amounts of matter and anti-matter in the beginning that mutually eliminated each other until all the anti-matter was gone. Because there was slightly more normal matter, there was some left and that's what creates the observable universe today. Thor 2 just added a Norse twist to the idea.