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New State of Matter Detected in a Two-Dimensional Material (phys.org)
An anonymous reader cites a report on Phys.org: An international team of researchers have found evidence of a mysterious new state of matter, first predicted 40 years ago, in a real material. This state, known as a quantum spin liquid, causes electrons -- thought to be indivisible building blocks of nature -- to break into pieces. The researchers, including physicists from the University of Cambridge, measured the first signatures of these fractional particles, known as Majorana fermions, in a two-dimensional material with a structure similar to graphene. Their experimental results successfully matched with one of the main theoretical models for a quantum spin liquid, known as a Kitaev model. The results are reported in the journal Nature Materials. Quantum spin liquids are mysterious states of matter which are thought to be hiding in certain magnetic materials, but had not been conclusively sighted in nature. The observation of one of their most intriguing properties -- electron splitting, or fractionalisation -- in real materials is a breakthrough. The resulting Majorana fermions may be used as building blocks of quantum computers, which would be far faster than conventional computers and would be able to perform calculations that could not be done otherwise.
What's worse is that Majorana fermions are their own anti-particle - so they have no charge - so if the electron split into three of them - where did it's charge go?
This stuff is *hard* to understand!
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There obviously are no "2-dimensional materials", just thin, 3-dimensional layers of material that may have interesting properties. Also, I don't believe for a second that "electrons break apart" in this "mystical" matter - this will most likely turn out to be just about some fancy maths, using fractional charges to describe a model of the "interesting properties". I stopped reading when the article started fantasizing about the use in quantum computers. That's the point where you know they just want to ride some hype in lieu of some substantial results they could present. Sorry for being so pessimistic - I'm a physicist, too.
Electrons cannot be divided into more fundamental particles. They're it, baby.
Uhm... I know Physics was a while ago for me - but can you point to some of that 'elementary science' that indicates how electrons have been thought to be divisible for 50 years?
At least wikipedia seems to disagree: "Electrons belong to the first generation of the lepton particle family,[9] and are generally thought to be elementary particles because they have no known components or substructure."
[ https://en.wikipedia.org/wiki/Electron ]
No.
No. It's all about pseudoparticles, which don't actually exist.
https://en.wikipedia.org/wiki/... has a better description. Click on the link to "fractionalization" which is what this article is talking about.
No, but we're one step closer to having a disintegration ray. Time to upgrade those sharks!
I came across this from 4yrs ago: http://www.popsci.com/science/...
The magnetic monopoles in spin lattices are "quasiparticles". They aren't fundamental particles. They are basically simulations of monopoles on a crystal lattice. But these crystal patterns can still exist at a quantum scale, so they still act like particles.
This explains it if you understand enough physics. http://www.nature.com/nature/j...
For all you folks who are more versed in electrical engineering than physics, a good example of a quasiparticle is positively charged "holes". These are a lot like electrons but are clearly not fundamental particles.
In the standard model, electrons are indivisible.
Protons and neutrons are made of quarks and are divisible, even though they really don't like it.
Since the past 100 years or so. They're point particles, which means they have no internal structure, and aren't composed of any other particles. They can be destroyed or created, but that's not division.
You can also split an electron's wavefunction into multiple pieces, so that it occupies certain distinct regions with various probability amplitude (and these split wavefunctions can actually have physical effects: while I'm not enough of an expert on condensed matter to say for sure, a quick skim of the paper indicates that something like that is what is happening here), that's a bit different from dividing the electron.
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the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Electrons were certainly thought to be indivisible when first discovered (see also, atoms, protons). The answer to "since when", because that's since the electron was discovered in 1897. But you meant to imply that the electron was already know to be constituted of component particles. So a better way to do that would be an incredulous "is this XXXX?" or similar that expressed a belief it was already common knowledge.
Pedantry aside, wikipedia tells me that all 6 leptons (which include electrons) are indivisible. So, I dunno. The Standard Model certainly assumes that they are.
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You've posted this multiple times. I dare you to explain why the dual slit experiments show electrons to be divisible.
Dual slot experiments show that electrons have wave-like properties. The electron is indivisible and point-like as far as we know. In quantum mechanics going through two slits at the same time does not mean you're divisible.
Dual slot experiments show that electrons have wave-like properties. The electron is indivisible and point-like as far as we know. In quantum mechanics going through two slits at the same time does not mean you're divisible.
Well, that's one of many areas where quantum mechanics gets hairy. If you see patterns where a single particle behaves like you'd expect from a system of particles (quasi-particles, pseudo-particles) does that mean it actually consists of even smaller particles or not even though we can't pull them apart and study them individually? I think that's the current state of quarks, even though atoms are made up from quarks we've never been able to pull a proton apart and study one in isolation.
I mean we can send sea waves against slits and see interference patterns. We send a single electron against slits and see interference patterns, it's one quantum wave interfering with itself. It's certainly possible to postulate that what we see as "one" particle/wave duality consists of many near-inifitely small other particles, held together by a force so strong we haven't got a name for it. And what we're seeing in the dual slit experiment is this collection of particles hitting a slit, interfering but not splitting, like a man with a dog on a leash going on separate sides of a lamp post.
That still wouldn't explain many other weird phenomenons like quantum entanglement though. Apparently if you take two entangled electrons and measure something on one you might get a 50-50 distribution but then when you measure the other it'll be exactly like the first one and vice versa so the order of the measurement collapses the wave function for both electons. But one doesn't exclude the other, some of the batshit weirdness might be because it consists of sub-electron particles and some not. I really don't see any other sane explanations for interference, but then QM is insane.
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A comment explains the "divisibility":