Is dark matter’s “nightmare scenario” true?
The great hope is that beyond the indirect, astrophysical evidence we have today, we’ll someday detect it directly. But what if we can’t?
There’s an enormous puzzle to the Universe, and it’s one that might remain puzzling for a long time: dark matter. For generations, now, it’s been recognized that the known law of gravity, Einstein’s General Relativity, combined with the matter and radiation that’s known to exist in the Universe — including all the particles and antiparticles described by the Standard Model of physics — doesn’t add up to describe what we see. Instead, on a variety of cosmic scales, from the insides of individual galaxies to groups and clusters of galaxies all the way up to the largest filamentary structures of all, an additional source of gravity is required.
It’s possible that we’ve got the law of gravity wrong, but if that’s the problem, it’s wrong in an extremely complicated way that also seems to require an additional source of matter (or something that behaves equivalently). Instead, the most common and successful hypothesis is that of dark matter: that there’s an additional form of matter out there, and we feel its gravity, but have yet to experimentally detect it. That hope, of direct experimental confirmation, is only possible…
