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Wave particle duality

  1. Nov 4, 2009 #1
    Ok, if a particle is a wave and can diffract (e.g. through graphite sheet), I mean does the particle split into two or something, or does the particle somehow 'transform' into a wave? Im always inquisitive about this question.
  2. jcsd
  3. Nov 4, 2009 #2
    In quantum mechanics, the wavefunction contains the state of the system. In that sense, there is no "wave-particle" duality, as everything is always a wave.

    The measurement postulate of quantum mechanics states that measuring the position will collapse the wave to those range of positions compatible with the measurement. It is still a wave, just initially highely "peaked" after a measurement.

    So it doesn't 'transform' into a wave. It always is a wave.
  4. Nov 4, 2009 #3
    Bohr explained wave particle duality using the idea of complimentarity. Have you ever seen that picture where if you think about it in one way it looks like an old woman and if you think about it another way it looks like a young woman?

    Here is the link if you haven't:

    http://www.coolopticalillusions.com/optical_illusions_images_2/images/youngwomanoldlady.jpg" [Broken]

    What Bohr suggested was that the wave picture and particle picture are like the old woman/young woman views. Neither view is really what the picture is of, but together they cover all the human ways of thinking about the picture. Objectively the lines that make up the picture exist independently of our ideas concerning their interpretation. Just as we can't "see" both the young woman and the old woman in the picture at the same time, we can't "see" entities as both waves and particles at the same time. They seem opposing and contradictory, but together they encompass all phenomena. The apparent contradiction is due to our human way of interpreting the phenomena. Bohr's point was that nature doesn't really care what we think of it. Opposites are compliments...its all very Zen. Definitely some Eastern philosophy creeping into science.
    Last edited by a moderator: May 4, 2017
  5. Nov 4, 2009 #4
    The simplest way to think about it (in the style of the de Broglie-Bohm interpretation) is to assume that there is a particle and a wave, and that the wave exerts a force on the particle. Nothing weird about that. Fully in agreement with the experimental data.
  6. Nov 7, 2009 #5
    It is interesting your ZEN reference. I sit ZAZEN. The recently departed Abbot of the Monastery with which I am associated John Daido Lori met with Bohm in the past and held seminars, recognizing the connection of the mind illusion of a self not recognizing that we are emerging entities from fundamental particles. We are observers of transmissions of all around us. These collapse in our mind into objects, sounds, ect. all that the senses observe. If only mind could get to the level and purity of wave/particle physics. So much mental illusion we carry. We sit Zazen to rid ourselves of this, to find the mind connected to the quarks. Takes a lifetime.
    I am currently reading Tim Maudlin's "Quantum Non-Locality and Relativity" in which he explains and dismisses all the current explanations of Bell's violation of inequality. One chapter he talks about the wave/particle theory of sub-luminal communication and explains the absurdity of the explanation. One unexplained variable- what is the article of communication. Interesting book.
    Jim Botta
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