The Deep Underground Neutrino Experiment - A lecture by Dr. Stefan Söldner-Rembold

The Long-Baseline Neutrino Facility and Deep Underground Neutrino Experiment are the largest international particle physics project ever built in the United States, hosted by Fermilab. DUNE is a groundbreaking experiment that will send the world’s most powerful neutrino beam from Fermilab’s particle accelerator complex 800 miles through the earth to the world’s most advanced liquid-argon neutrino detector, which will be located one mile underground at the Sanford Underground Research Facility in South Dakota. More than 1,000 scientists from institutions in over 30 countries are working on DUNE. They seek to find out the role neutrinos play in the universe and look for rare subatomic interactions never seen before. Are neutrinos the reason that the universe is filled with matter? How do they contribute to the formation of black holes? In this hour-long public lecture Dr. Stefan Söldner-Rembold, professor at the University of Manchester and co-spokesperson of the DUNE collaboration, presents the latest information on this project. For further information see www.fnal.gov and www.fnal.gov/dune/ .

[@johnathanhenley2251]

The spice must flow!

[@xSUBIACOx]

A neutrino walks into a bar. Someone asked him if he wanted a pint. The neutrino said, "No thanks, I'm just passing through!"

[@mentalimage2241]

That's hilarious

[@Do_Odles]

Lovely lecture, great speaker -thank you

[@justincotra6851]

great lecture was impressed by the clarity of the SM

[@feelingzhakkaas]

great lecture and excellent presentation ...very beautiful

[@GratefulFrog]

Thanks again Stefan for the great presentation. You are an inspiration speaker and teacher! I wish I could remember the relationship between DUNE and the Swindon magic-roundabout! Cheers!

[@kaushaltimilsina7727]

Wow! Incredible!

[@Emcee_Squared]

Questions: 1. We know neutrinos are almost as fast as light, but what is their official speed? Has it been measured? 2. Does a neutrinos speed change as the neutrino oscillates into higher mass generations? 3. The tau neutrino is very heavy, and it travels at relativistic speeds.. Does that make it a good contender for dark matter? 4. If it doesn't get it's intrinsic mass from the Higgs field, then where does it's mass come from?

[@BrunoPST2010]

I'm gonna try to help a little bit with the questions: 1. Since neutrinos have mass, it does not make sense to ask what is their "official" speed, since speeds below the speed of light are not absolute -- for massive particles, there's always a reference frame in which the particle is at rest. 2. The thing is precisely that, rigorously speaking, the flavor neutrinos propagating in free space do not have well-defined speeds; what happens is that its components (the mass eigenstates) propagate at different group velocities because of their different masses, and that's what causes the oscillations in the first place. You'd have to think of neutrinos as wave packets in this approach, in order to make sense of the oscillation behavior. 4. The mechanism by which neutrinos acquire mass is not contained in the Standard Model, so the official answer for that would be that we simply don't know. However, there are some proposals, the most famous of which is the so-called see-saw mechanism. About the 3rd question, I really don't know anything specific, but neutrinos are indeed one of the candidates for dark matter.

[@Emcee_Squared]

@@BrunoPST2010 Thanks for taking the time to answer these questions. With regard to the first question, I ask that because Dr. Stefan mentions in the lecture above that we can detect the neutrinos a few seconds before we can detect the light from a supernova, so I imagine the speed at which these neutrinos travel at must be fairly steady, just under the speed of light. And the fact that they have no Higgs interaction may also play a role in this. I will have to look up this "see-saw" mechanism and research some of the current hypotheses for how they obtain mass.

[@BrunoPST2010]

@@Emcee_Squared Indeed, the typical speed at which neutrinos are emmited in these processes is very close to the speed of light, precisely due to their small masses; but I imagine that neutrinos arrive earlier than light from the supernova has more to do with the fact that whereas the photons are constantly being scattered inside the supernova -- which effectively "traps" them and make them take longer to leave it -- the neutrinos almost don't interact and just fly off instantly.

[@Emcee_Squared]

@@BrunoPST2010 Yes, that is how I understand it too. The photons "bump" into a lot of things as they make their way out of the star, but the neutrinos go through without touching a thing. That, and the fact that they travel at near light speed, means they are detected even before the light. It's pretty amazing.

[@MrAlRats]

@@Emcee_Squared Neutrino emission occurs during the core collapse while light is produced when the shock wave reaches the surface of the star.

[@rafihussain]

Good luck. Fermi lab

[@justincotra6851]

seems logical that stuff ie particles of energy get smaller and smaller as processes on the big scalehappen over time, however does it nececarilly play a role just because it exists?

[@Ouvii]

A scientist concludes their experiment shows that neutrinos travel faster than light. The bartender says "we don't serve faster than light particles here" a neutrino walks into the bar

[@amirsadeghi9888]

what about the people that are in the path of the neutrino burst? Shouldn't this be done in remote areas???

[@xSUBIACOx]

Love how he had to convert worldwide metric, into silly American imperial measures so you lot could understand, lol. "Here Chuck, what's that 'metre' thing he just said?" "Fucked if I know, Meryl!"

[@tumbleddry2887]

yeh....one more embarrassing thing we have to deal in the US with these days

[@MCToon]

I think we should all switch to livestock based units. Starting the length. One sheep is the average length of all the sheep in Scotland. It can get re-evaluated every 10 years. Mass is measured in German Shepherds. Average mass is all shepherds in Germany. Not just dog based shepherds. Volume is measured in Male Spring Break using volume. All other units are available for definition.

[@procactus9109]

@@MCToon Americans wont get it. It has to be 'football fields' and 'empire state buildings'. Power is measured in DVD players.

[@relaxingnature2617]

The only thing more abundant than neutrinos is the amount of times this guy said ah ah ah ah ah ....

[@Bobby-fj8mk]

I can't see any useful information that will ever be gained by studying the neutrino except to satisfy our curiosity. On the other hand - studying the electron led to millions of applications and has helped us in almost every part of our lives. Can neutrino research ever be justified?

[@JohnPKING-nj8nc]

"Can neutrino research ever be justified?"

[@WilliamLeeSims]

I know this is silly, but Dune has a great logo. It's filled with subliminal outreach.

[@procactus9109]

To me, seeing those wigs pick up a shovel full of dirt and throw it back down is a big slap in the face to the people involved with actually making the device.

[@jerrygundecker743]

a neutrino just flew past my ear. It missed my by that much. Whew! That was a close one.

[@thetherorist9244]

....the mathematics show that you are trying to witness the future by measuring the distance between photons and neutrinos....bet you wondered how I know this?

[@khalifaofthemosthigh6853]

They are planning to use Neutrio as a specialized refined fuel to initiate time travel.

[@cherryg.3042]

Khalifa Of The Most High who is they? ASA

[@paulcalhounwaser7971]

Physicists have observed tachyons, so they are no longer “hypothetical.” Most physicists do not know it, but all neutrino speed measurements have yielded average speeds slightly faster than the speed of light. And the neutrinos’ rest mass-squared has been measured from neutrino oscillations, and they are negative. The square-root rest masses are thus imaginary. According to special relativity, positive relativistic mass must always travel slower than the speed of light. Conversely, negative relativistic mass must always travel faster than the speed of light. Thus, neutrinos have negative relativistic mass and negative-imaginary rest mass. Neutrinos are tachyons and cannot rest but must travel faster than the speed of light in a vacuum. Although we would measure neutrinos time as going slightly backward rather than stopped like light, they do not actually go there at all. Everything we see and measure is in the past, but nothing goes there. There is no “tachyonic antitelephone.” I have uploaded several papers on all these properties to Academia.com.

[@johnfarris6152]

You want to really mess with their minds, just say "On Earth as it is in Heaven."

[@laralara6799]

@23:00 @41:00

[@rkpetry]

*_..."neutrino...out...instantly" [_**_12:43_**_] but not straightly-scattering thousands of times..._* *_...tbd why is the neutrino only affected by the weak force yet it bounces on electrons..._*

[@jelinlikeafelin]

Electrons also interact weakly

[@scottanderson8167]

Didn’t he give this talk a couple years ago?

[@yootoob6003]

You know how it goes, giving talks at symposiums and conferences... Just rejig your last .ppt you presented at a previous symposium...

[@scottanderson8167]

Yoo Toob that makes sense.

[@douglasgreene5197]

I think I understand the standing wave within a wave. Seems obvious.

[@sakadabara]

おっばいチョコ

[@executivesteps]

Uh!

[@3Space1time]

First

[@xSUBIACOx]

Of all thosse 1,000 scientists ~ Not one African???

[@philipsmith7904]

If neutrino can pass through lead for a year without being stopped , why can the deep n trap only capture 1 per hour instead of millions of them ?