3 ms·

Doing the two slit experiment with electrons and actual slits is absolutely trivial, and that link doesn't say what you think it means.

kgwgk 7y ago
“The general perception is that the electron double-slit experiment has already been performed. This is true in the sense that Jönsson demonstrated diffraction from single, double, and multiple (up to five) micro-slits [2], but he could not observe single particle diffraction, nor close individual slits. In two separate landmark experiments, individual electron detection was used to produce interference patterns; however, biprisms were used instead of double-slits [3, 4]. First, Pozzi recorded the interference patterns at varying electron beam densities. Then, Tonomura recorded the positions of individual electron detection events and used them to produce the well known build-up of an interference pattern. It is interesting to point out that the build up of a double-slit diffraction pattern has been called 'The most beautiful experiment in physics' [5, 6], while the build-up for a true double-slit has, up to now, never been reported.” https://iopscience.iop.org/article/10.1088/1367-2630/15/3/033018/meta https://iopscience.iop.org/article/10.1088/1367-2630/15/3/03...
- scottlocklin 7y ago
  I did the experiment in 1989, closing individual slits and everything. There are entire fields of material science based on photo electron interference (ARPES, XPS and other photo emission spectroscopies). Quoting some clown who claims "well you never did it my (irrelevant) way" is not useful here.
  - kgwgk 7y ago
    If you think that citing a paper by a physics professor in a peer-reviewed physics journal is “quoting some clown” you’ll probably understand that I don’t give much weight to a comment from a random person on HN.
    - scottlocklin 7y ago
      You're perfectly free to believe in ghosts, the flat earth or DMT elves as well. People who know what they're talking about are still going to laugh at you. Do you think clowns who publish physics papers (and yes, those guys are grade-A quacks for writing that paper with such claims) are immune to the temptations of PR balognia? Do you really think "Ultramicroscopy" is a reputable physics journal? Had someone actually done something as innovative as his claims: it would be in Science, Nature and PRL. But I guess you don't actually know anything about physics and think google substitutes for knowledge and "muh links" substitute for argument.
      - kgwgk 7y ago
        For what it’s worth, one of the clowns who coauthored that Ultramicroscopy paper is credited with the first observation of the build-up of the interference pattern from individual electron detections in 1974 (using an electron biprism, not slits in a plate).
        scottlocklin 7y ago
        I'm sure their motion picture tells us all about it. PR != reality.
        kgwgk 7y ago
        What’s the reality then? Let’s accept for the sake of the argument that it’s a clownish thing to do in the 21st century to report that you’re sending electrons one by one (at intensities low enough so the interaction is necessarily that of independent particles, not that of a beam) towards a metal plate with two slits (which can be opened and closed at will) and detecting the arrival of individual electrons at the other side as independent events. Because that’s a trivial thing to perform and thousands of students were doing it already in the eighties. You say that if it was innovative it would be in the cover of Nature or something. When would you say it was done for the first time then? Was it published in a top-tier journal when it was innovative? If not, why not?

kgwgk 7y ago

“The general perception is that the electron double-slit experiment has already been performed. This is true in the sense that Jönsson demonstrated diffraction from single, double, and multiple (up to five) micro-slits [2], but he could not observe single particle diffraction, nor close individual slits. In two separate landmark experiments, individual electron detection was used to produce interference patterns; however, biprisms were used instead of double-slits [3, 4]. First, Pozzi recorded the interference patterns at varying electron beam densities. Then, Tonomura recorded the positions of individual electron detection events and used them to produce the well known build-up of an interference pattern. It is interesting to point out that the build up of a double-slit diffraction pattern has been called 'The most beautiful experiment in physics' [5, 6], while the build-up for a true double-slit has, up to now, never been reported.” https://iopscience.iop.org/article/10.1088/1367-2630/15/3/033018/meta https://iopscience.iop.org/article/10.1088/1367-2630/15/3/03...

scottlocklin 7y ago
I did the experiment in 1989, closing individual slits and everything. There are entire fields of material science based on photo electron interference (ARPES, XPS and other photo emission spectroscopies). Quoting some clown who claims "well you never did it my (irrelevant) way" is not useful here.
- kgwgk 7y ago
  If you think that citing a paper by a physics professor in a peer-reviewed physics journal is “quoting some clown” you’ll probably understand that I don’t give much weight to a comment from a random person on HN.
  - scottlocklin 7y ago
    You're perfectly free to believe in ghosts, the flat earth or DMT elves as well. People who know what they're talking about are still going to laugh at you. Do you think clowns who publish physics papers (and yes, those guys are grade-A quacks for writing that paper with such claims) are immune to the temptations of PR balognia? Do you really think "Ultramicroscopy" is a reputable physics journal? Had someone actually done something as innovative as his claims: it would be in Science, Nature and PRL. But I guess you don't actually know anything about physics and think google substitutes for knowledge and "muh links" substitute for argument.
    - kgwgk 7y ago
      For what it’s worth, one of the clowns who coauthored that Ultramicroscopy paper is credited with the first observation of the build-up of the interference pattern from individual electron detections in 1974 (using an electron biprism, not slits in a plate).
      - scottlocklin 7y ago
        I'm sure their motion picture tells us all about it. PR != reality.
        kgwgk 7y ago
        What’s the reality then? Let’s accept for the sake of the argument that it’s a clownish thing to do in the 21st century to report that you’re sending electrons one by one (at intensities low enough so the interaction is necessarily that of independent particles, not that of a beam) towards a metal plate with two slits (which can be opened and closed at will) and detecting the arrival of individual electrons at the other side as independent events. Because that’s a trivial thing to perform and thousands of students were doing it already in the eighties. You say that if it was innovative it would be in the cover of Nature or something. When would you say it was done for the first time then? Was it published in a top-tier journal when it was innovative? If not, why not?