"Dark," cosmologists call it, in what could go down in history as the ultimate semantic surrender. This is not "dark" as in distant or invisible. This is "dark" as in unknown for now, and possibly forever.
If so, such a development would presumably not be without philosophical consequences of the civilization-altering variety. Cosmologists often refer to this possibility as "the ultimate Copernican revolution": not only are we not at the center of anything; we're not even made of the same stuff as most of the rest of everything. We're just a bit of pollution, Lawrence M. Krauss, a theorist at Case Western Reserve, said not long ago at a public panel on cosmology in Chicago. "If you got rid of us, and all the stars and all the galaxies and all the planets and all the aliens and everybody, then the universe would be largely the same. We're completely irrelevant."
All well and good. Science is full of homo sapiens-humbling insights. But the trade-off for these lessons in insignificance has always been that at least now we would have a deeper "simpler" understanding of the universe. That the more we could observe, the more we would know. But what about the less we could observe? What happens to new knowledge then? It's a question cosmologists have been asking themselves lately, and it might well be a question we'll all be asking ourselves soon, because if they're right, then the time has come to rethink a fundamental assumption: When we look up at the night sky, we're seeing the universe.
Not so. Not even close.
