Amazing ways to look for dark matter

Dark matter remains one of the unsolved mysteries of modern physics. In this video, Fermilab’s Dr. Don Lincoln explains two innovative methods whereby Fermilab scientists are looking for types of dark matter largely overlooked by the broader community.

Fermilab physics 101:

Fermilab home page:

[Grandunifiedcelery]

You finally made a "Physics is everything" T-shirt😁

[jvkurtz]

Hey, Dr. Lincoln, you forgot to equip your moustache

[crashmancer]

I like the part about how “we’re not sure how heavy dark matter is, but it’s somewhere between the smallest particle we can imagine and an unusually large black hole.”

[williamhenry]

The starting point here is there’s a missing particle out there. Since we’re really talking about “ dark gravity”, how about a comment on all the other theories to explain the observations ( MOND, quantum inertia, etc.)

[justpaulo]

It isn't only dark matter we can't find... Dr. Lincoln mustache is gone too!

[OldGamerNoob]

Nice, simple description for what Axions would be but an angle I hadn't heard before. Thanks!

[XionLuis]

Moustacheless Dr Lincoln. What parallel universe must I've been teleported to?!

[johnmorin]

Uh oh, is his mustache made of virtual particles popping into and out of existence?

[cauchym]

Looks like there's a bunch of Myazaki fans at the Sensei team. 😄

[thedemongodvlogs]

As weird as it is to see dr. Lincoln without a moustache, i gotta say your looking great doc!

[zirize]

4:49 'sensei' physicists know memes.

[SamudraSanyal]

Why are physicists so obsessed with particles? Our most accurate theory of gravity is based on curvature of spacetime, which for regular matter happens with mass/energy but couldn't dark matter just be some type of intrinsic topography of spacetime and galaxies end up clustering near those topographic features?

[busybillyb]

Dr. Don has time travelled back to his younger self to produce this video.

[RME]

Nice presentation!

OK, here's an admittedly far-fetched idea.

1) Neutrinos pour out of the Sun at rates of about 2 * 10^38/second and photons about 10^45/second. These numbers may be off, but the idea is, a huge number of neutrinos are emitted. Surely, with the number of stars in a galaxy (let alone the Universe), there is an enormous flood of neutrinos screaming silently and almost invisibly through spacetime.
2) Neutrinos are notoriously difficult to detect because they interact extremely weakly with ordinary matter.
3) The mass of a neutrino is incredibly small, about 1/500, 000 that of an electron (again, the value may be off, but it gives a sense of their relative mass).
4) Neutrinos are continuously produced by stars so the net mass of neutrinos in a galaxy at any given moment should be fairly large and anything but 'insignificant, ' and the local density would be, assuming no external forces influencing their flight path**, would be akin to an inverse distance-squared law.
5) BUT, WHAT IF something IS influencing the neutrinos during their flight?

Perhaps some form of neutrino shock waves forming where the local density is far higher than in regions of spacetime where they travel more-or-less under no external influence?

If neutrinos could undergo compression (not unlike a gas experiences in, say, a normal shock in a supersonic jet and, in this case, by causes unknown) to form regions of higher density during their flight, is the resulting mass of the standing shock wave region(s) and its potential location(s) sufficient to account for a non-negligible amount of the estimated mass of dark matter?

Neutrinos are thought to oscillate between three different flavors. What if the number of oscillation cycles has some statistical limit at which time they decay into a different (presently unknown and more massive) form or an entirely different particle (that interacts strongly with gravity, but is otherwise 'invisible')?

Yeah, I know, nothing but questions, conjecture and the vivid imagination of somebody that watches every episode of Dr. Don and Dr. Matt.

** I muse, a neutrino's path is in a straight line, but, spacetime is warped due to mass, with greater degrees of warping around more massive objects such as Sun-like stars up to behemoth black holes, so, like photons, they too follow curved paths through spacetime as a consequence and thus there should be pockets of lesser and greater neutrino densities just as there are for photons that show, for example, in gravitational lensing.

[Onegod-vh]

#question the vacuum energy of free space has been estimated to be 10^−9 joules, or ~5 GeV per cubic meter.However, in quantum electrodynamics, consistency with the principle of Lorentz covariance and with the magnitude of the Planck constant suggest a much larger value of 10^113 joules per cubic meter. Where is the problem?

Making a video on it will be helpful Sir

[NathanZamprogno]

Could it be that we’re just in a region of space that has no dark matter to detect?
I’ve seen maps that predict regions of dark matter between galaxies to account for specific observed lensing. If those results suggest dark matter is denser in some regions than others, maybe we’re just in a barren area?

[misterphmpg]

Thanks for another great video. Maybe you could explain also the hints of dark matter hidden in the cosmic microwave background which might cause the observed mass structures of the very early universe.

[ooiirraa]

#question: I understand why dark matter particles with the mass of the sun are ruled out by astronomy. But why massive subatomic particles are roled out by physics? Might at be that they are there, but they just don't interract with matter at all? So they are not toally ruled out? Or?

[eliadbu]

I think that sometimes it can frustrating to look for somethings you can't be sure they exist, especially when you look for them for decades.

[sir-yzcw]

You're a fantastic educator, doc. Please keep up the great work. Thank you.