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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.
Spelling it correctly would be a worthwhile milestone on your quest.
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.
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.
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.
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.
Well, there's spam egg sausage and spam, that's not got much spam in it.