Dark Universe
You know dark matter, the mysterious stuff that most physicists now believe makes up the bulk of the universe — even though it remains completely undetectable, except for its gravitational effects on regular matter?
There’s no shortage of far-out theories about the hypothetical material: that it’s hiding inside an extra dimension, that it originated in a second Bing Bang, that it’s information itself, or even that it doesn’t exist at all.
Now, as spotted by Flatiron Institute astrophysicist and indefatigable science journalist Paul Sutter, a new paper offers yet another exotic potential explanation: that dark matter resides in a deformed mirror universe inside of own, where atoms failed to form.
Coincidencer
As Sutter explains, the research builds off a pair of intriguing coincidences. First, observations suggest that there’s a roughly comparable amount of regular and dark matter out there (tipped a bit toward dark matter, which is believed to outweigh conventional matter by a factor of about five.) And second, neutrons and protons have almost precisely the same mass, allowing them to form stable atoms — a fortuitous property, because otherwise our universe wouldn’t be host to any of the lovely atoms that make up stuff like stars, planets, and ourselves.
Basically, the theory goes, maybe there’s a shadow universe to our own in which neutrons and protons don’t have that convenient symmetry in mass, meaning the whole thing is a sad soup of subatomic particles that don’t interact much, explaining why dark matter doesn’t seem to clump up much.
Important to note: the paper isn’t yet peer reviewed, and it’s just another theory among many jostling to crack the mysteries of dark matter, a galling and lingering unknown in our understanding of the universe. But it does have an impressive author list, with researchers ranging from Fermilab to the University of Chicago — so we’ll be watching to see how it’s received in the broader world of physics.
More on dark matter: China Opens Huge Underground Dark Matter Lab