Neutrino 'Flip' Discovery Earns Nobel For Japanese, Canadian Researchers 58
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.
Re:Nice, but... (Score:4, Informative)
Spelling it correctly would be a worthwhile milestone on your quest.
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Repeating memes isn't an "internet" thing, it's an "idiot" thing.
As a Canadian (Score:5, Funny)
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As a Canadian Particle Physicist (Score:5, Informative)
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 (Score:5, Interesting)
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.
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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.
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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 t
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Neither, the point is scientific hubris almost always gets bitch slapped by reality;
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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 (Score:4, Informative)
Like much of science, discoveries are based on previous work. Starting in the 1960s physicists encountered the solar neutrino problem [wikipedia.org]. 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.
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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
Gabor Fekete (Score:2)
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I get all my science from Morgan Freeman, thank you very much.
"Flipped?" (Score:2)
You sure the neutrinos, they're not mutating?
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78 to 100 Planck lengths.
Important info missing from summary (Score:3, Insightful)
Newts and Rhinos (Score:2)
Alternately - they switch between tasting of one and the other. Obvious really.
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So what exactly does a neutrino taste like?
Probability says: Chicken.
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Reversing the polarity of the Neutron Flow... (Score:3, Funny)
Suddenly sounds a lot more feasible.
Re:Disappointing prize (Score:5, Informative)
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 [arxiv.org] which has direct applications in the field of nonproliferation [newscientist.com]. Here's a map of the world [technologyreview.com] as a function of its antineutrino flux [nature.com]. 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.
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If you want a practical application of neutrino detectors and their relevance today ...
Neutrino detectors may also be useful in high frequency trading [forbes.com]. That is certainly an application that benefits the common people.
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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
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'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.
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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.
Re:Disappointing prize (Score:5, Informative)
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" [nobelprize.org]. 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.
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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 thermod
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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?
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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.
Neutrino 'Flip' Discovery by Prof McDonald (Score:2, Funny)
Original Slashdot post on SNO Results (Score:1)
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... [slashdot.org]