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You are correct that we must not use languages at all in physics only technical sketches of experiments and their results.
IF YOU CAN'T SHOW THE COMPLETE SET-UP OF THIS EXPERIMENT THIS REALLY TELLS US ... NOTHING.Out of all the talk on double slit experiments, I have never heard anything about how electrons or light interact with the material of the slits. I am use to using RHEED/LEED (electron diffraction) in semiconductor manufacturing, where the reflection pattern off the atomic latice of a material builds up 1 electron at a time (nothing 'spooky'). Similarly, could the double-slit be the same with the patterns just being the electron reflection/diffraction off the atomic lattice of the edges of the slit material?Then you get an ?interference?/build-up envelope from the 2 electron patterns from 2 slits. If it is just electron reflection/diffraction off the atomic lattice of the slit material, then even if one electron at a time, you naturally get a gradual build-up of a reflection/diffraction pattern off the atomic lattice. Nothing mysterious. Maybe no need for some 'spooky' quantum explanation?Also, on the ?measurement destroys interference pattern? issue, I think it has been shown in recent years (by an Italian group) that when an atom/electron detector is there, usually in front of the slit, it of course disturbs such electron scattering, so the interference pattern changes (it seems if electron has inelastic scattering with detector, pattern changes. If elastic scattering with detector, pattern doesn?t change). Again, for measurement, seems nothing 'spooky', probably like a detector naturally disturbs a tennis ball?s trajectory.Any papers with experimental evidence of any effects on the electrons from the atomic lattice of the slit material?
Double-slit experimentQuantum MeasurementYou may be familiar with an experiment known as the " double-slit experiment," as it is often introduced at the beginning of quantum-mechanics textbooks. The experimental arrangement can be seen in Fig. 1. Electrons are emitted one by one from the source in the electron microscope. They pass through a device called the "electron biprism", which consists of two parallel plates and a fine filament at the center. The filament is thinner than 1 micron (1/1000 mm) in diameter. Electrons having passed through on both sides of the filament are detected one by one as particles at the detector. This detector was specially modified for electrons from the photon detector produced by Hamamatsu Photonics (PIAS). To our surprise, it could detect even a single electron with almost 100 % detection efficiency.At the beginning of the experiment, we can see that bright spots begin to appear here and there at random positions (Fig. 2 (a) and (b)). These are electrons. Electrons are detected one by one as particles. As far as these micrographs show, you can be confident that electrons are particles. These electrons were accelerated to 50,000 V, and therefore the speed is about 40 % of the speed of the light, i. e., it is 120,000 km/second. These electrons can go around the earth three times in a second. So, they pass through a one-meter-long electron microscope in 1/100,000,000 of a second. It is all right to think that each electron is detected in an instant after it is emitted.Interference fringes are produced only when two electrons pass through both sides of the electron biprism simultaneously. If there were two electrons in the microscope at the same time, such interference might happen. But this cannot occur, because there is no more than one electron in the microscope at one time, since only 10 electrons are emitted per second.Please keep watching the experiment a little longer. When a large number of electrons is accumulated, something like regular fringes begin to appear in the perpendicular direction as Fig. 2(c) shows. Clear interference fringes can be seen in the last scene of the experiment after 20 minutes (Fig. 2(d)). It should also be noted that the fringes are made up of bright spots, each of which records the detection of an electron.We have reached a mysterious conclusion. Although electrons were sent one by one, interference fringes could be observed. These interference fringes are formed only when electron waves pass through on both sides of the electron biprism at the same time but nothing other than this. Whenever electrons are observed, they are always detected as individual particles. When accumulated, however, interference fringes are formed. Please recall that at any one instant there was at most one electron in the microscope. We have reached a conclusion which is far from what our common sense tells us.
Although electrons were sent one by one, interference fringes could be observed. These interference fringes are formed .....
Quote from: hamdani yusuf on 25/08/2024 16:57:54 Although electrons were sent one by one, interference fringes could be observed. These interference fringes are formed .....I have my doubts about this phraseology.Yes, there is a spatially periodic distribution of electrons which can be modelled as the interference of waves, But whilst it is clear that waves can interfere constructively or destructively, what arrives at the electron detector are single electrons with single charge (no constructive interference) and we do not have a mechanism by which two charges of the same sign or two identical masses can annihilate each other (no destructive interference). Therefore it is not an interference pattern.
This is the second video about photomultipliers and their use. In this video I set out to measure an effect called "Photon Bunching". Photon bunching is phenomenon characteristic for incoherent light It can for example be used to measure the angular diameter of stars and was discovered by Robert Hanbury Brown and Richard Quintin Twiss in 1954.Video chapters:0:00 Introduction0:42 Brief description of coherence4:01 Description of the experimental setup10:17 Aim of the experiment11:40 Main result12:25 Explanation and discussion13:10 What is a photon?16:10 Relation field amplitude / intensity / probability 22:17 Second order correlation function described 25:23 The Hanbury Brown & Twiss effect27:25 Trying to measure g(2); failure and succssAll wave animations in this video were produced using a Python script supplied by @DiffractionLimited . Thank you very much Manuel for supplying me with this tool.Third party imagery and clips:14:35 Image standard Model of elementary particles: Source WIkipedia14:55 I got the "face slap" clip of a channel named @neilsandwichtv5186. Not sure if this channel indeed is the copyright owner. Contact me if you have more info on this.13:36 I used a few very short clips from @ArvinAsh as illustrations of the particle presentation of light and photons. Arvin makes very high quality content on various scientific subject. But I guess his photon visualizations leave some room for improvement (;-).
Photomultiplier (PMT) principle, operation and measurements explained.In the follow-up video, I'll demonstrate an experiment involving single photon measurements using photomultipliers: ? Photon Bunching / Hanb... 00:00 Intro and overview00:30 The photoelectric effect 02:11 Detecting single photons03:33 How a PMT detects a photon10:35 How to operate a PMT17:00 Measurements with a photomultiplier24:59 Conclusions
Therefore it is not an interference pattern.
What phrase do you prefer?
Two electrons can repel each other, causing their absence from a particular position in space and time.
The pattern is affected by the design of the double slit aperture, as well as the detector. If the image of the pattern in previous post is zoomed in, the dots can be seen as somewhat boxy. I think it's a feature of the detector, instead of the electrons.
It is the distribution of electrons passing through multiple slits.
but that would occur at random and is just as likely to happen where we observe a maximum as it would at a minimum, so you'd expect to get a continuous blur, not a periodic pattern. And we observe the same pattern with neutrons.
If you keep the detector constant, the pattern varies with the number and position of the slits and can be precisely (for a sufficient number of electrons) calculated from those parameters, so it isn't a function of the detector.
The pixels in the detector can be shaped as 2D array of triangles, rectangles, or hexagons. Their size and the distance between individual pixels can also be set intentionally.
Quote from: hamdani yusuf on 20/10/2024 12:29:48The pixels in the detector can be shaped as 2D array of triangles, rectangles, or hexagons. Their size and the distance between individual pixels can also be set intentionally.Or you can use a single detector and move it to detect maxima and minima. It doesn't matter what detector you use, the pattern remains the same. Time was that we used photographic film for x-ray crystallography, and nowadays mostly use CCD detectors, but the answer hasn't changed. Similarly with electron diffraction patterns.
So what?
so it isn't a function of the detector.