Neutrino 'Flip' Discovery Earns Nobel For Japanese, Canadian Researchers

Dave Knott writes with news that the 2015 Nobel Prize in physics has been awarded to Takaaki Kajita (of the University of Tokyo in Japan) and Arthur McDonald (of Queens University in Canada), for discovering how neutrinos switch between different "flavours." As the linked BBC article explains: In 1998, Prof Kajita's team reported that neutrinos they had caught, bouncing out of collisions in the Earth's atmosphere, had switched identity: they were a different "flavour" from what those collisions must have released. Then in 2001, the group led by Prof McDonald announced that the neutrinos they were detecting in Ontario, which started out in the Sun, had also "flipped" from their expected identity. This discovery of the particle's wobbly identity had crucial implications. It explained why neutrino detections had not matched the predicted quantities — and it meant that the baffling particles must have a mass. This contradicted the Standard Model of particle physics and changed calculations about the nature of the Universe, including its eternal expansion.

Comments

As a Canadian

[SuiteSisterMary]

Sorry we hosed up your Standard Model, eh.

Re:As a Canadian

[fraxinus-tree]

Well, it wasn't that good anyway.

Re:As a Canadian

[UnknowingFool]

Like much of science, discoveries are based on previous work. Starting in the 1960s physicists encountered the solar neutrino problem. Ray Davis in the Homestake Experiment was trying to detect solar neutrinos but was only getting 1/3 of the amount he expected. But he could repeatedly get the same results. Either he was wrong or the Standard Model was wrong. In the 1980s, Masatoshi Koshiba confirmed Davis' results using a different technique with the Kamiokande II. For some reason there were far fewer solar neutrinos than predicted by the Standard Model.

In 1998, Takaaki Kajita's work at Kamiokande's successor, Super Kamiokande, gave hints at what may be causing the discrepancy. While the results were not conclusive and dealt with muon neutrinos, it suggested that the amount of neutrinos was in agreement with the Standard Model but that they were oscillating or changing into different flavors which previous experiments were not set up to detect. At the Sudbury Neutrino Observatory (SNO) in 1999, Arthur MacDonald and his team were able to confirm that solar neutrinos oscillate.

For their work, all four men have now received the Nobel Prize because they showed that the Standard Model of physics was wrong about something fundamental. Initial explanations about the discrepancy suggested that physicists were wrong about how the sun (and stellar fusion) works. The physicists were correct; however, they were wrong about the nature of neutrinos. Originally it was thought that neutrinos have no mass but by oscillating, neutrinos must have some mass even it is very, very small.

Re:As a Canadian

[lgw]

This work was huge, because it showed that neutrinos move slower than light. The "flip" was an inspired solution to the missing neutrino problem, as it required a string of assumptions that moved away from the "consensus": that neutrinos move slower than light, that they can "spontaneously" change flavor, and do so frequently, which meant assuming that there was some mechanism to allow the flip without the neutrinos interacting with something. Really quite a reach theoretically, but fully justified by the data.

This is common for the great physics breakthroughs: the evidence that the current model is wring is obvious, often for years, before someone has the inspiration of just how to accommodate the new data cleanly - often by moving far indeed from the current model. This wasn't relativity or QM, but it was still an impressive leap.

Gabor Fekete

[itamblyn]

Until Gabor Fekete weighs in on this, I'm unconvinced.

Re:Gabor Fekete

[KGIII]

I get all my science from Morgan Freeman, thank you very much.

Re:Nice, but...

[allcoolnameswheretak]

Spelling it correctly would be a worthwhile milestone on your quest.

"Flipped?"

[meta-monkey]

You sure the neutrinos, they're not mutating?

Re:"Flipped?"

[OakDragon]

Neutrinos are not stand-up guys.

Ridiculous

[Anonymous Coward]

If you notice from the summary these particles were "detected in Ontario". Since these neutrinos are clearly Canadian you can expect that they would differ strongly from neutrinos detected in other parts of the world. For example, maybe they obtained a coating of maple syrup or were dipped in poutine? Likewise the researchers were from Japan and Canada, thus you can expect additional differences. That is why it is important to call out the geographic area of the people involved when announcing Nobel Prizes.

Re:Ridiculous

[OakDragon]

I have to consult the exchange rates to see how the Canadian neutrino is faring against the American neutrino.

Re:Ridiculous

[KGIII]

78 to 100 Planck lengths.

Neutrinos only?

[Anonymous Coward]

They forgot Electrinos and Protinos.

Important info missing from summary

[Nidi62]

So what exactly does a neutrino taste like?

Re:Important info missing from summary

[willworkforbeer]

So what exactly does a neutrino taste like?

Probability says: Chicken.

Re:Important info missing from summary

[Anonymous Coward]

I don't care what they taste like until they bring back Lime!

Re:Important info missing from summary

[Spinalcold]

Before tasted they are both triple fudge chocolate and not. At the time you measure it, by tasting it, it becomes either fudge or...I'll let you figure out the other 'fudge' flavour.

As a Canadian Particle Physicist

[Roger W Moore]

While it is physics beyond the Standard Model it is really easy to incorporate it into the model. In fact it makes the leptons more like the quarks in that they now both have a mixing matrix.

It's fantastic to hear that Art finally won the Nobel though - many of us were wondering how long it would be before he did! It's very well deserved for a discovery which was at least as significant, and far more surprising, than the Higgs.

Re:As a Canadian Particle Physicist

[budgenator]

I remember Isaac Asimov saying "Either everything we know about particle physics is wrong, or the sun has gone out; therefore the sun has gone out". in regards to neutrino flip.

Re:As a Canadian Particle Physicist

[tehcyder]

I remember Isaac Asimov saying "Either everything we know about particle physics is wrong, or the sun has gone out; therefore the sun has gone out". in regards to neutrino flip.

So which was it then? Don't leave us in suspense.

Re:As a Canadian Particle Physicist

[Anonymous Coward]

The Sun Has Gone Out.

Fortunately for us that transition started in the core, and it'll take millions of years to propagate out to the surface.

Re:As a Canadian Particle Physicist

[daknapp]

It's fantastic to hear that Art finally won the Nobel though - many of us were wondering how long it would be before he did!

Indeed he does deserve it. His tenacity is legendary. SNO is amazing.

Oh, and I now feel ever so slightly more important, as he was my thesis advisor.

Re:As a Canadian Particle Physicist

[esonik]

Well, no. Since neutrino oscillations are confirmed we are good again as we expect to see only 1/3 of the total neutrino flux (the other 2/3 are the two neutrino flavours muon- and tau-neutrinos that our detectors are not sensitive to)

Before the experimental proof, most scientists tended to side with the Standard Model, i.e. massless neutrinos and therefore no oscillations - which meant that seeing only 1/3 of the expected neutrino flux from the sun indicates something's wrong, either with the sun or with the model of the sun predicting neutrino flux.

Re:As a Canadian Particle Physicist

[budgenator]

Neither, the point is scientific hubris almost always gets bitch slapped by reality;

Re:Nice, but...

[Anonymous Coward]

Understanding memes would be a breakthrough on your quest of understanding that crazy "internet" thing the kids are doing.

Reversing the polarity of the Neutron Flow...

[dlingman]

Suddenly sounds a lot more feasible.

Newts and Rhinos

[Viol8]

Alternately - they switch between tasting of one and the other. Obvious really.

Disappointing prize

[ganv]

It is disappointing to see the high energy physicists continue to dominate the nobel prize. Since the 1930s, anyone who discovers some new quirk about some fundamental particle gets the prize. Nevermind the fact that the discovered particle properties steadily become less and less relevant to anything that affects humans in any practical way. When Chadwick discovered the Neutron, that deserved a Nobel Prize. In many ways it was the beginning of nuclear physics. Neutrino mass was a nice puzzle. They (partly) solved it. Good work. But who cares? The future of physics is either to become solvers of interesting but irrelevant puzzles (which will be funded at the level that society funds other impractical but fascinating fields like poetry or classical music), or to become solvers of fundamental quantitative problems in materials science, environmental science, engineering, biology, and computational science that society needs solved. The overwhelming majority of actual physicists have already realized this fact and moved to work on relevant problems. But the nobel prize committee is stuck on the old path to irrelevance. The physiology prize is given to scientists who developed cures for parasitic diseases that affects many people while the physics prize goes to the discovery of a property of particles that can only be indirectly measured with massive detector. And we wonder why physics seems uninteresting to the next generation?

Re:Disappointing prize

[Anonymous Coward]

interesting but irrelevant puzzles

Like "why does this lump of rock ruin my film?" and "as if we'd ever figure out how to stick two atoms together?"

If you want a practical application of neutrino detectors and their relevance today, you need look no further than Online Monitoring of the Osiris Reactor with the Nucifer Neutrino Detector which has direct applications in the field of nonproliferation. Here's a map of the world as a function of its antineutrino flux. It's a little low-res as of last month, but it looks really interesting - as in, it's a map of every nuclear reactor on earth - once you subtract out the background from decay of naturally-occurring elements in the crust.

Not only have we used knowledge of new fundamental particles to learn how to split and fuse the atom to release energies that would have been unimaginable to the Curies, we can use knowledge of newer, harder-to-detect, and "irrelevant" fundamental particles to detect bad actors trying to build bombs on the sly. If the fundamental particles underlying the first nuclear war are Nobel-worthy, surely the particles that are being measured in order to prevent history's second nuclear war, ought to be worthy of consideration, even if nobody's figured out how to make a bomb out of them.

Re:Disappointing prize

[Anonymous Coward]

'Practical' uses for developments in advanced physics take a long time to be realized. Einstein wrote a paper called "Emission and Absorption of Radiation in Quantum Theory" in 1916. Basically the fundamentals of lasers. It took another 44 years for the first laser to be built. CDs weren't being sold until the 80s. Stop asking "What does it do NOW??" You sound like a child. Grow up and understand that science is a long term strategy.

Re:Disappointing prize

[Anonymous Coward]

High energy physics can lead the way to fusion energy. That is critically important and will affect many future generations in a real way. I would think that figuring out that neutrinos actually have mass is pretty important. If anything else, it proved my professors wrong when they taught us that neutrinos don't have mass. I never understood how something that actually exists cannot have mass. It is counter intuitive and really turned me off from the entire field. It makes physics sound like magic. This continues today with the insistence that "dark matter" exists.

Re:Disappointing prize

[Crowd Computing]

It is disappointing to see the high energy physicists continue to dominate the nobel prize. Since the 1930s, anyone who discovers some new quirk about some fundamental particle gets the prize.

I'm not sure what you mean by dominate but a significant share of prizes awarded in the last fifteen years were for physics with clear practical applications, including LEDs (2014), graphene (2010), fiber optics and CCDs (2009), giant magnetoresistance (2007), laser spectroscopy (2005), and the integrated circuit (2000). The 2003 prize was given for "contributions to the theory of superconductors and superfluids". Other years the prizes was awarded for astrophysics: 2011, 2006 and 2002. The other prizes appear to be for quantum physics, but not all of them deal with LHC-type of high energy physics.

Re:Disappointing prize

[Anonymous Coward]

At least it isn't a prize going to a politician for being elected.

Re:Disappointing prize

[Anonymous Coward]

The future of physics is either to become solvers of interesting but irrelevant puzzles (which will be funded at the level that society funds other impractical but fascinating fields like poetry or classical music), or to become solvers of fundamental quantitative problems in materials science, environmental science, engineering, biology, and computational science that society needs solved.

Why are you advocating doubling up on the amount of funding going to those things when classically fundamental physics discovers have been groundbreaking. Nobels aren't for things with immediate practical implications, they're for things that need to be done and nobody else will work on. Those "puzzles" will eventually lead to very useful things.

Re:Disappointing prize

[Bengie]

The prizes go to groups that solve or answer questions that are very hard to answer, not just because iterative technology has allowed them to create better materials.

Re:Disappointing prize

[ganv]

By dominate I mean 2 of the last 3 prizes and a fraction of recent prizes that is far larger than the fraction of physicists that work on high energy physics. (I count 6 out of 21 prizes since 1995 in high energy physics, or 28% to a community that is something like 15% of the American Physical Society). We simply haven't figured out how to recognize the more important contributions in less reductionist and more applied areas of physics. Last year's prize for semiconductor LED breakthroughs was a step in the right direction. But going back to neutrinos so quickly reflects the prize committee doesn't really get it.

Re:Disappointing prize

[Anonymous Coward]

If Alfred Nobel wanted to give out a Prize for Engineering, he would have done so. But then, he had no fondness for Mathematicians either.
Also, note that Nucleosynthesis is still a vibrant field, but a Nobel for the discovery of a new Element was last awarded in 1951. In Chemistry.
I'm not sure what field of Physics that you are in, that is so obviously neglected, but a lot of Nuclear Physicists, Nuclear Chemists, Accelerator Physicists, Detector Physicists, and Atomic Physicists are involved in Neutrino Research. It's a Branch that involves many Disciplines. But my guess is that you are actually a Wanker. Neutrino Research is not High Energy Physics.
Best current guesses for Neutrino Masses are in the milli-electron Volt region, and most reactions responsible for their production are in the MeV range.
Not much High Energy there.
By all means get rich and Endow a Medal for the Field or Fields that you feel are being neglected.
They can call it the Wanker Prize.

Re:Disappointing prize

[ShanghaiBill]

If you want a practical application of neutrino detectors and their relevance today ...

Neutrino detectors may also be useful in high frequency trading. That is certainly an application that benefits the common people.

Re:Disappointing prize

[cellocgw]

By dominate I mean 2 of the last 3 prizes and a fraction of recent prizes that is far larger than the fraction of physicists that work on high energy physics. (I count 6 out of 21 prizes since 1995 in high energy physics, or 28% to a community that is something like 15% of the American Physical Society). We simply haven't figured out how to recognize the more important contributions in less reductionist and more applied areas of physics. Last year's prize for semiconductor LED breakthroughs was a step in the right direction. But going back to neutrinos so quickly reflects the prize committee doesn't really get it.

So, what you're really saying is that there needs to be a minimum average amount of rest mass per Physics Nobel Prize, and the recent trend is underweight?

Re:Disappointing prize

[Anonymous Coward]

Do neutrino oscillations affect the detection and calculations associated with non-proliferation? Do they come into play?

Is there engineering application of GeV+ physics (quark engineering or GeV+ physics that goes into applications outside physics, such as nuclear weapon design or nuclear reactor design)? Is MeV theory enough to do all this?

If GeV energies go beyond engineering applications, how about TeV+ energies? The cost goes up, does the generated wealth keep pace?

Re:Disappointing prize

[Alomex]

Sorry but you are wrong. The question has to be first of all interesting. I can come up with a million different rather hard to answer questions that do not deserve a Nobel Prize, and yes, particle physics is over represented among the Nobel prizes. I have no opinion if this particular batch deserves it or not, but overall you need a result twice as good outside particle physics to get the Nobel prize.

Re:Disappointing prize

[ganv]

Alfred Nobel's will says that his estate should fund 'prizes to those who, during the preceding year, shall have conferred the greatest benefit to mankind'. He lived in an age when physics was the study of the fundamental problems facing engineers of his day. Look at the careers of Kelvin or Helmholtz or Maxwell to see how closely tied these areas were. (Kelvin built transatlantic telegraph equipment, Maxwell developed color photography and studied bridge design, Helmholtz worked on physiology and thermodynamics inspired by applied science). I suspect the distance between modern fundamental particle physics and practical benefits to humanity might seem very foreign to Nobel were he alive to see it.

My concern is not actually for a subfield of physics. Applied research is often better funded than traditional reductionist physics. My concern is for physics as a discipline, and for the career path our brightest young aspiring physicists are directed down. We are at a cross-roads. Either physics will be the search for ever more fundamental models of the constituents of matter that become ever more irrelevant, and all the useful work will be done by people who call themselves something else. Or physics will become the application of quantitative models to fundamental problems in wide areas of science, and much of modern science will become ever more indistinguishable from applied physics. In the former case physics drifts into obscurity. In the latter case, physics strengthens its place as the central and fundamental science.

Re:Disappointing prize

[Anonymous Coward]

Do you really believe that HFT benefits common people?

Besides that it's impractical, the energy you need to spend to generate a modulated flux of neutrino and detect it at the other end is so large that the energy costs would probably dwarf the profits.

Re:Disappointing prize

[Anonymous Coward]

Physicist here, although not a particle physicist. Photons have no mass, they only have an energy (and momentum). Special relativity implies that massless particles move at the speed of light. Particles are always associated with waves from basic quantum mechanics. All of this is basic and fairly easy to understand physics. Now quantum field theory and general relativity are another matter.

Re:Disappointing prize

[Anonymous Coward]

You are sort of missing the point. You claimed... here, I'll quote you:
"It is disappointing to see the high energy physicists continue to dominate the nobel prize."
And:
"By dominate I mean 2 of the last 3 prizes and a fraction of recent prizes that is far larger than the fraction of physicists that work on high energy physics."

As far as Particle/Nuclear Physics goes, Neutrino Research is about about as Low Energy as one can go. Cosmically, its average Energy is lower than the average Energy of the CMB background, which is something of a problem, because really Cold Neutrinos are interesting, and there should be a lot of them, but they are currently undetectable. More Engineering needed.
You have some Ax to grind about High Energy Physics. Fine. I'm reassured at this point that you aren't a Physicist. You are uninformed about the Field_s_. Eloquent, yes, but uninformed.
And there is no shortage of bright, young and enthusiastic Physicists just starting out. I hired a number of them.

I looked through some of your past posts, and you dance around whatever Field you are really in.
I'm an Accelerator Physics guy. One of the things I was involved in was the whole 7B+P=>8Be=>2Alpha+WeirdassNeutrinos affair, which was and is messy. I provided the P, at a variety of MeV, yet the Cross Sections still just don't look right. Others carry on.
I also did some Detector work, for which I was awarded one of the rarer of the Physics Prizes a decade back. (Not for SNO; for Gammasphere. But I also worked on SNO later. And ATLAS. More P, at much higher MeV, for that last one.)

Re:Disappointing prize

[Anonymous Coward]

I wonder if that tech can be used to spot/locate/track where nuclear submarines are?

Re:Disappointing prize

[Blaskowicz]

It likely can't : with fixed reactors you can accumulate a year of neutrino data, with submarines they're always on the move. We can imagine putting a mesh of dozens or hundreds neutrinos detectors on the ocean floors (or otherwise have a lot of neutrinos detectors in many places, ocean or sea floor is just one place they can work) at a staggering cost, not sure if that would work.

On the global antineutrino map 2015 you can't even see the low power reactors in Israel and North Korea (one for each) that are only used for producing bomb plutonium. But they're likely turned off or used infrequently.

Re:Disappointing prize

[Blaskowicz]

I don't understand how anything exists at all. Let's say energy from the Big Bang is not a problem (because it came from vacuum energy from.. somewhere). Then everything should be energy/photons and equal parts of matter and antimatter that meet and convert to energy then equal parts matter and antimatter again and over again.

Not African researchers then?

[Anonymous Coward]

I am surprised. No I'm not actually. Are you? Care to discuss?

Thought not.

Neutrino 'Flip' Discovery by Prof McDonald

[Anonymous Coward]

McFlip to be offered soon at McDonald's everywhere.

Re:Neutrino 'Flip' Discovery by Prof McDonald

[Anonymous Coward]

Dr. Richard McDonald's Neutrino involvement was in Low Background Counting, Neutrino Detector Research, and with an added interest in old Mercedes Diesels.
It was once his hunch that lots and lots of Buckyballs were to be found in the soot of Mercedes Diesel Tailpipes.
And so they were.
I'm not making this up.
It started a new, still small, field of Complex Carbon Combustion Engineering, about two decades back.
He still drives a Diesel, in retirement.

Re:Nice, but...

[Anonymous Coward]

Repeating memes isn't an "internet" thing, it's an "idiot" thing.

Loving it!

[Anonymous Coward]

My wife, a particle physicist a FermiLab (biggest neutrino experimental lab in the world) must be loving this! Of course, she doesn't like to discuss her work with me since I am just a lowly engineer... :-) I have to read Physics Today or such to get the news!

Re:Loving it!

[Anonymous Coward]

A woman that I used to work with, and then for, is a Plasma Physicist specializing in the Plasmas of Very High Charge State Heavy Ions. Her husband is a Mechanical Engineer. She thinks things up, he designs things so that they work, with a minimum of Explosions or Implosions, and when she goes to Conferences, he babysits.
I remember when their second Girl was born. Wife just took a few days off for that, and went right back to work.
They are a very happy Family, and that second Girl starts College next year.
My Best to you and yours...

Original Slashdot post on SNO Results

[akunak]

I think this is the original 2001 Slashdot post from SNO (Sudbury Neutrino Observatory) in Sudbury, Ontario. It did not attract much Slashdot discussion at the time.

http://science.slashdot.org/st...

I thought

[Anonymous Coward]

scientific fudge had a factor rather than a flavour?

Is this the new math again?