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I've found a way to see electrons! (?)

  1. Jul 29, 2007 #1
    I've found a way to "see" electrons! (?)

    So why can't we see electrons in the double slit experiment? Because if we throw photons at them and it changes its velocity/momentum. Hence we can't "see" through which slit the electron goes in a double slit experiment. My basic idea is that we cant see electrons because they are tiny and the matter around us is in bunches of matter particles (or particle waves or strings or whatever). So if we somehow "Bunch" the electrons we can see them directly or indirectly. (hope not just a thought experiment :redface: )

    If we replace the electron gun used in the experiment with a -ve lectrode of high voltage (really high) and replace the screen with a metal plate connected to ground and carry the experiment...

    We will charge the electrode with high voltage and an electric discharge will travel through the air through either or both slits and strike to a point/patch on the metal plate. As the electrons will strike large number of atoms through their way to the screen it will create large number of photons which will be scattered in all directions uniformly. So we can actually "see" and determine the position of electrons. We will click a photograph at the instant when this happens and "see" exactly through which slit the electrons traveled.

    It will also cheat the uncertainty princeple (wont it?). Will the charge on the electrons somehow create error in this experiment? Is my experiment fundamentally wrong in some way? What if the experiment is carried in pure H2O? Can we see through which path electrons travel by the buble produced in water? ( wont electrons traveling in water somehow create bubbles through their way?) Or can i expect to win the next nobel title? ( like SRSLY :yuck: ) (sorry for bad english. im indian)
  2. jcsd
  3. Jul 29, 2007 #2
    I think you don't quite understand a few basic concepts. First, I don't know what you think an "electon gun" is, but your description of an electrode with a high negative voltage describes it fairly well. It's called an "anode" in that case, and the grounded plate would be the cathode, but the concept is pretty much the same.

    As for the basic idea you have, however, it amounts to a way to observe the electrons, so all those interactions with the photons collapse the electons' wave functions, preventing them from passing through the slits as they would have without the observations.

    This is all consistent with QM, and in fact, many introductory texts suggest just your idea, but they also consider reducing the photons' energy to smaller and smaller levels to minimize the impact on the electrons. Go find such a text, and you'll gain some more insight into this problem.

    Good luck in your interest in this subject.
  4. Jul 29, 2007 #3


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    Er... Look at my avatar. Those are "pictures" of many electrons hitting a CCD. This is done in many experiments, and in this case, it is from a photoemission experiment. We "image" electrons (and other charged particles) all the time. How do you think they track charged particles in particle accelerators? In fact, we can even "track" the motion of individual electrons, as illustrated in a recent paper.

    Being able to DETECT or image electrons is neither new nor unusual, and certainly does NOT "cheat" the HUP, unless you hold the common misconception about the HUP.

  5. Jul 29, 2007 #4


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    NO! We cannot 'see' electrons by any means.

    Any physical interaction with a particle will affect its position/momentum/energy.

    The uncertainty principle holds.

    Electrons scatter of the electrons in the atoms/molecules, just as the would scatter off gas atoms in a gas filled container. Think of 'neon' lights, or gaseous discharges in glass vessels.

    Normally one would perform such an experiment in a vacuum.

    One would 'see' a track which indicates the path that an electron (or ionizing radiation) takes - i.e. where it has been.
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