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  I just got an even stronger evidence that diffracted light is produced by the edges of the obstacle, instead of the space between those edges.
  Quote from: hamdani yusuf on 26/07/2024 06:52:27I just got an even stronger evidence that diffracted light is produced by the edges of the obstacle, instead of the space between those edges. Isn't that obvious? Diffraction = light appearing in the geometric shadow areaNo edge = no shadow
  A bit of optics fun and a little riddle: two coherent light beams of equal intensity and opposite phase meet up. They interfere destructively in the center, thereby creating a continuous plane of zero EM field (and so of zero intensity). The question is: how can the energy in either beam cross and area of zero intensity? Leave a comment if you want to show off your intellect ;-). The experiment in the last 20 seconds of the video shows the cross section of 2 laser beams that meet up and part again. For the experiment I used a single coherent source (HeNe-laser), because that is the only way this experiment could work. It requires a fairly high degree of coherence. Basically it's just a 50% beam splitter and an adjustable mirror under 45 degrees, that create 2 beams of equal intensity, initially spaced 4mm apart, 1mm in diameter and are under an angle of 0.1 degrees with respect to each other. I moved the camera sensor over a distance of 6 meters and recorded 40 images around the area where the beams were crossing paths.
  The QM answer is "tunnelling".
  The question is: how can the energy in either beam cross and area of zero intensity? Leave a comment if you want to show off your intellect ;-).
  My intuition might be wrong, but it makes me think of mechanical waves. Energy can still travel through nodes of a string even though they don?t move.
  That is right, standing wave nodes can pass energy. The confusion starts when you think in terms of "beams" or EM radiation being build up of localized "packages" of energy. What you observe are just wave interference phenomena, nothing more.
  The use of reflecting/transmitting beam splitter causes a phase inversion in one of the resulting two beams (the reflected beam). That's why when they interfere after traveling the same distance, the result is a destruction interference. You can try to use a polarizing beam splitter such as Wollaston prism, and you'll get no destructive interference. You can also try to use a diffraction grating, and isolate the beam going to the left and right of the same order. You'll get a constructive interference in the center instead of destructive interference.
  Here are some examples of simulation for double slit experiments.
  3d scenes on 2d film, and a diffraction lesson along the way.Slight correction: In the end, I referenced treating |R^2| as "some real number", so that it's only scaling O. This only makes sense to do because the amplitude of R is constant, or at least it varies only very slowly around a point. In this way, what I say a few moments later about making no assumptions about R is not quite right, we do assume it's a wave with relatively constant magnitude across the film.
  In the same side double edge diffraction-interference pattern, the central bright fringe is approximately three times as wide as the other bright fringes. Note that the fringes on the left side are slightly wider than those on the right side. That's because the position of the camera was on the left of the central spot.
  Do you have an example that can't be analysed by Huygens and he usual superposition equations? Excluding, of course, your hybrid diffraction-reflection-refraction pattern from a thick transparent "edge", or diffraction of a polychromatic beam.
  How do you analyze the previous same side diffraction-interference pattern? Can you do it using wavelets based on Huygens' principle?
  Quote from: hamdani yusuf on 08/11/2024 10:12:06How do you analyze the previous same side diffraction-interference pattern? Can you do it using wavelets based on Huygens' principle?I could, because I know light travels away from the source, but someone masquerading as yourself on another topic, seems to think otherwise.