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Physicists Just Generated a Particle That Acts as Its Own Antiparticle
- CurtMonash 9y agoI guess it would be tough to keep these around in any substantial quantity.
- thaumasiotes 9y agoIt's not usually a problem to have a large number of photons?
- adrusi 9y agoWhich are different because the result of a particle/antiparticle collision is the emission of photons so the quantity of photons is not changed by collisions.
- m3kw9 9y agoUnless it can only become one of the properties at one time
- CurtMonash 9y agoWell up above the tropostrata There is a region stark and stellar Where, on a streak of anti-matter Lived Dr. Edward Anti-Teller. Remote from Fusion’s origin, He lived unguessed and unawares With all his antikith and kin, And kept macassars on his chairs. One morning, idling by the sea, He spied a tin of monstrous girth That bore three letters: A. E. C. Out stepped a visitor from Earth. Then, shouting gladly o’er the sands, Met two who in their alien ways Were like as lentils. Their right hands Clasped, and the rest was gamma rays. by Prof. Harold P. Furth (1930-2002)
- mmastrac 9y agoUgh, science writing: > Physicists Just Generated a Particle That Acts as Its Own Antiparticle [...] > Physicists now have the next best thing – a particle-like system that behaves just like the kind of matter Majorana predicted
- lateadopter 9y agoYep, title is bad, better would be "Physicists Just Generated a Fermion That Acts as Its Own Antiparticle", or more concisely: "Physicists Just Generated a Majorana Fermion". All bosons (e.g. photons) are their own antiparticle, so this is a rare instance of science writing where the headline is LESS interesting than the actual work done.
- gus_massa 9y agoIf you talk with someone that works in solid state physics, they act as if these kind of particles were real as elementary particles. The most usual are holes [1] and phonons [2]. So it's standard notation in that area, but it may be confusing for the general public. At least they didn't call it an "angel" particle, like in the previous submissions. [1] https://en.wikipedia.org/wiki/Electron_hole https://en.wikipedia.org/wiki/Electron_hole [2] https://en.wikipedia.org/wiki/Phonon https://en.wikipedia.org/wiki/Phonon
- jessriedel 9y agoThe distinction between fundamental particles and composite particles is more a statement about the extent of human knowledge rather than anything physical about those particles. That is, saying "this is a fundamental particle" tells you that we haven't discovered any constituent parts to it, not that there aren't any. Protons used to be fundamental particles until we discovered they were made of quarks, and quarks may yet turn out to be composite particles built from preons. So yes, if you were attracted to this article because you thought they found a new fundamental particle, then it was clickbait. But the real point is that it's a Majorana fermion (with well-defined momentum eigenstates, a scattering matrix, etc.). It's possible in the future that we discover neutrinos are Majorana fermions https://en.wikipedia.org/wiki/Double_beta_decay#Neutrinoless_double_beta_decay https://en.wikipedia.org/wiki/Double_beta_decay#Neutrinoless... at which time they will be "fundamental Majorana fermions"... and then discover after that the neutrinos are just composite particles. https://arxiv.org/abs/1510.07988 https://arxiv.org/abs/1510.07988 (There are some subtleties here. Some quasi-particles don't have all the properties we normally associate with fundamental particles. And there are weak theoretical arguments that some fundamental particles can't be composite unless their constituents have properties that are subjectively inelegant.)
- ColinWright 9y agoMost of the discussion is here in this submission, but there are also two comments here: https://news.ycombinator.com/item?id=14817322 https://news.ycombinator.com/item?id=14817322 And there's another comment here: https://news.ycombinator.com/item?id=14818725 https://news.ycombinator.com/item?id=14818725 There are also other submissions: https://news.ycombinator.com/item?id=14817206 https://news.ycombinator.com/item?id=14817206 https://news.ycombinator.com/item?id=14833208 https://news.ycombinator.com/item?id=14833208 https://news.ycombinator.com/item?id=14840123 https://news.ycombinator.com/item?id=14840123
- rbanffy 9y ago> for every type of fundamental particle in the Universe there is the equivalent of an evil twin complete with an opposing charge Do they have goatees?
- exabrial 9y agoSo did I but I can't find it.....
- c517402 9y agoI have personally been producing particles that are there own anti-particles since childhood. And, I continue to do so as I write this comment. Photons!