"Light years…have never been proven”? Uh….what? What the hell does this person think a light year IS? That’s like saying, oh I dunno…”miles haven’t been proven.” Light travels at a certain speed, we can measure it, and hence, a light-year is (oddly enough) the distance light travels in a year. Is he saying we haven’t measured the speed of light, or something?
And I don’t think anyone is actually saying parallel universes ARE proven. It’s a hypothesis at best, really.