There’s a lot of chatter right now in the physics world that we may have evidence that
dark matter is Sterile Neutrinos.
Finally I can stop disinfecting my hands every time I touch Neutrinos.
Hello there viewers, Julian here for DNews.
There has been no direct evidence of dark matter, only things that strongly suggest
it must exist.
But now however, we may be on to something.
The European Space Agency’s XMM-Newton spacecraft has noticed an unusual spike in X-ray radiation
coming from the Andromeda galaxy and the Perseus Galaxy cluster.
As our own Dr. Ian O’Neill explains in this article, Atoms and baryonic particles give
off distinct electromagnetic spectrums, but this spike doesn’t correspond to any we
know about.
So something hitherto unseen must be the culprit.
While the discovery is fascinating, I want to take a minute to explain in depth what
he means by baryonic particles, because it’s something that links the very small to the
super-massive.
Be warned, I’m going to have to explain the basics of quantum mechanics, but learning
this will make you cool and interesting at parties.
So subatomic particles are divided into Bosons and Fermions based on their spin; the Bosons
have an integer spin, and the ones we’ve discovered are either 0 or 1.
There are Gauge bosons which carry force; Gluons carry the strong force, Z and W Bosons
carry the weak force, and our old friend the photon carries the electromagnetic force.
Then there’s the Higgs Boson, which comes into existence when the Higgs field is excited.
It proves that the Higgs field exists, and the Higgs field explains away some problems
of the standard model.
With me so far?
Good, because it’s about to get weird.
That brings us to Fermions, which have half-integer spins.
Fermions are divided into Quarks and Leptons.
We’ve discovered Quarks have 6 flavors; Up and Down, Charmed and Strange, and Top
and Bottom.
How these quarks are combined gives us different composite subatomic particles, some of which
you already know.
For instance, two Ups and a Down make a proton, while two Downs and an Up make a neutron.
These are called baryons, and they react to all 4 fundamental forces; the strong force,
the weak force, gravity, and electromagnetic radiation.
Because of that last one, we can observe baryonic matter directly.
That brings us all the way back to dark matter; the theory is that since we can’t see it
but we can observe its gravity, maybe it’s non-baryonic.
Now if you were keeping fastidious notes you’ll notice the Fermion group I haven’t explained
yet are Leptons.
We’ve discovered 3 charged leptons, one of which is the electron, and 3 neutral Leptons,
which are 3 different flavors of the neutrino.
Neutrinos have no charge and very small mass, making them extremely hard to detect because
they hardly interact with anything.
In fact every square centimeter of your skin gets hit with 65 BILLION neutrinos per second.
But they just pass right on through, like listless vagabonds.
It’s been proposed that there is a 4th flavor of Neutrino, the Sterile Neutrino.
It’s called that because it would ONLY react to something through a gravitational pull.
They don’t even react weakly with other matter like their 3 cousins.
They’d be almost impossible to detect.
But if there’s enough of them, they could account for the gravity that keeps entire
galaxies from flinging stars off into space.
And maybe, just maybe, some sterile Neutrinos are decaying and causing this weird spectrum
of x-ray radiation.
Or maybe they don’t exist at all and I just spent the last 5 minutes scrambling your brain
for nothing.
If you want to take a step back and review the 4 fundamental forces again so you can
get your head around some of this, Trace and I cover that in this video here.
If you’ve got questions or thoughts on Dark Matter, I’d love to hear them in the comments.
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