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The text by the New Scientist, now retold by the Daily Mail (why now? just the "content spam" I guess), is from July 2014 (!): https://www.newscientist.com/art

by acqq 11y ago

The text by the New Scientist, now retold by the Daily Mail (why now? just the "content spam" I guess), is from July 2014 (!): https://www.newscientist.com/article/mg22329802-300-pigeon-paradox-reveals-quantum-cosmic-connections/ https://www.newscientist.com/article/mg22329802-300-pigeon-p... It would be surprising that DM covers such a subject first? The PDF of the work: http://arxiv.org/abs/1407.3194 http://arxiv.org/abs/1407.3194 The first and the third listed authors: https://en.wikipedia.org/wiki/Yakir_Aharonov https://en.wikipedia.org/wiki/Yakir_Aharonov http://www.bristol.ac.uk/physics/people/sandu-popescu/ http://www.bristol.ac.uk/physics/people/sandu-popescu/

cbd1984 11y ago
Can the link be replaced with one of these?
- acqq 11y ago
  If replaced by the first it needs (2014). Mods?
lagudragu 11y ago
From the New Scientist article: "This device splits each electron into two, sends them along both paths simultaneously, then brings them together again." http://phys.org/news/2015-05-electron.html http://phys.org/news/2015-05-electron.html The experiment reveals that, when a single electron fractionalizes into two pulses, the final state cannot be described as a single-particle state, but rather as a collective state composed of several excitations. For this reason, the fractionalization process destroys the original electron particle. Electron destruction can be measured by the decoherence of the electron's wave packet.
- acqq 11y ago
  Which "source text"? For all I know, the electron as such can't be split and remain the electron, especially not produce "two" electrons. And especially whatever is produced by splitting the electron we won't be able to recombine it in an electron. Some journalists and some news sources simply like to distort the science. "It's OK for their target population or their business model." This article in Nature (Apr 2015) was the source for that phys.org thing: http://www.nature.com/ncomms/2015/150421/ncomms7854/full/ncomms7854.html http://www.nature.com/ncomms/2015/150421/ncomms7854/full/nco... What I understand they do is they demonstrate some quantum effect not actually splitting the electron. And where did you find that phys.org link? And what's your "source text" from which you gave the quote? Daily Mail links to the 2014 New Scientist article I've already linked and doesn't have these sentences?
  - lagudragu 11y ago
    I got the "source text" from the New Scientist article (https://www.newscientist.com/article/mg22329802-300-pigeon-paradox-reveals-quantum-cosmic-connections/ https://www.newscientist.com/article/mg22329802-300-pigeon-p...), I have corrected this statement. I did get the phys.org link through a google search on splitting electrons with interferometers. The experiment that they produced did "split up" the electron, as they stated, into two fractionalized packets carrying half of the original electron charge.
    - acqq 11y ago
      Good, so now it's clear that Daily Mail really just retells the article from July 2014. Regarding experiment from 2015, they never "split" the electron as such, they just claim to observe some "temporal" "partial" excitations in their setup. Which surely can be something interesting, but there's also a lot of work done before https://en.wikipedia.org/wiki/Fractionalization https://en.wikipedia.org/wiki/Fractionalization "Laughlin proposed a fluid of fractional charges in 1983" etc "Fractional charges continue to be active topic in condensed matter physics." It's not that the single particle is actually being split, even if it appears so. That's why there's talk about "quasiparticles" and "fractional charges." https://en.wikipedia.org/wiki/Fractional_quantum_Hall_effect https://en.wikipedia.org/wiki/Fractional_quantum_Hall_effect
mratzloff 11y ago
I don't quite understand the pigeonhole concept as it relates to the pigeons. Is the thought experiment saying that if they check each pigeonhole they'll only ever find one pigeon? Even with infinite pigeons, they'll only find one? (And presumably all the other pigeons will occupy the other roost?) I'm not quite following.
- acqq 11y ago
  The start of the PDF of the authors, better than the articles: "The pigeonhole principle: "If you put three pigeons in two pigeonholes at least two of the pigeons end up in the same hole" is an obvious yet fundamental principle of Nature as it captures the very essence of counting. Here however we show that in quantum mechanics this is not true! We find instances when three quantum particles are put in two boxes, yet no two particles are in the same box." That's quantum physics. Our experiences from the "big world" don't match what's going on there. The "electron" is a particle (called so for our convenience, like other particles) but it doesn't behave like anything from the macroworld. And take care finding what the "boxes" actually in this case are.
- deleted 11y ago
  [deleted]

by acqq 11y ago

cbd1984 11y ago

Can the link be replaced with one of these?

acqq 11y ago
If replaced by the first it needs (2014). Mods?

lagudragu 11y ago

From the New Scientist article: "This device splits each electron into two, sends them along both paths simultaneously, then brings them together again." http://phys.org/news/2015-05-electron.html http://phys.org/news/2015-05-electron.html The experiment reveals that, when a single electron fractionalizes into two pulses, the final state cannot be described as a single-particle state, but rather as a collective state composed of several excitations. For this reason, the fractionalization process destroys the original electron particle. Electron destruction can be measured by the decoherence of the electron's wave packet.

acqq 11y ago
Which "source text"? For all I know, the electron as such can't be split and remain the electron, especially not produce "two" electrons. And especially whatever is produced by splitting the electron we won't be able to recombine it in an electron. Some journalists and some news sources simply like to distort the science. "It's OK for their target population or their business model." This article in Nature (Apr 2015) was the source for that phys.org thing: http://www.nature.com/ncomms/2015/150421/ncomms7854/full/ncomms7854.html http://www.nature.com/ncomms/2015/150421/ncomms7854/full/nco... What I understand they do is they demonstrate some quantum effect not actually splitting the electron. And where did you find that phys.org link? And what's your "source text" from which you gave the quote? Daily Mail links to the 2014 New Scientist article I've already linked and doesn't have these sentences?
- lagudragu 11y ago
  I got the "source text" from the New Scientist article (https://www.newscientist.com/article/mg22329802-300-pigeon-paradox-reveals-quantum-cosmic-connections/ https://www.newscientist.com/article/mg22329802-300-pigeon-p...), I have corrected this statement. I did get the phys.org link through a google search on splitting electrons with interferometers. The experiment that they produced did "split up" the electron, as they stated, into two fractionalized packets carrying half of the original electron charge.
  - acqq 11y ago
    Good, so now it's clear that Daily Mail really just retells the article from July 2014. Regarding experiment from 2015, they never "split" the electron as such, they just claim to observe some "temporal" "partial" excitations in their setup. Which surely can be something interesting, but there's also a lot of work done before https://en.wikipedia.org/wiki/Fractionalization https://en.wikipedia.org/wiki/Fractionalization "Laughlin proposed a fluid of fractional charges in 1983" etc "Fractional charges continue to be active topic in condensed matter physics." It's not that the single particle is actually being split, even if it appears so. That's why there's talk about "quasiparticles" and "fractional charges." https://en.wikipedia.org/wiki/Fractional_quantum_Hall_effect https://en.wikipedia.org/wiki/Fractional_quantum_Hall_effect

mratzloff 11y ago

I don't quite understand the pigeonhole concept as it relates to the pigeons. Is the thought experiment saying that if they check each pigeonhole they'll only ever find one pigeon? Even with infinite pigeons, they'll only find one? (And presumably all the other pigeons will occupy the other roost?) I'm not quite following.

acqq 11y ago
The start of the PDF of the authors, better than the articles: "The pigeonhole principle: "If you put three pigeons in two pigeonholes at least two of the pigeons end up in the same hole" is an obvious yet fundamental principle of Nature as it captures the very essence of counting. Here however we show that in quantum mechanics this is not true! We find instances when three quantum particles are put in two boxes, yet no two particles are in the same box." That's quantum physics. Our experiences from the "big world" don't match what's going on there. The "electron" is a particle (called so for our convenience, like other particles) but it doesn't behave like anything from the macroworld. And take care finding what the "boxes" actually in this case are.
deleted 11y ago
[deleted]