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Heisenberg's principle

  1. Dec 13, 2008 #1
    Hi, I've a doubt!
    The principle says that we cannot find simultaneity the position and the momentum of a particle, I understand this because if I haven't understood bad it's because to find the position of a particle we need to trhow photons to it (and more and more) as much as we want to be precis and this changes its velocity.

    The one i don't understant is the one of time and energy. Why can't we find both exactly?

  2. jcsd
  3. Dec 13, 2008 #2
    Energy defines how particle interact with the others. So you need to give it some time to interact.
  4. Dec 13, 2008 #3
    Energy is a kind of cumulation effect. If you want to survey the energy of a system accurately, you need some time. So the time becomes inaccurate.
  5. Dec 13, 2008 #4
    It's the inequality obeyed by the deviation of the energy distibution of the states forming a wave packet that evolves with a wave function [itex]\Psi(t)[/itex]. In other words, a relation between the energy distribution of a wave packet and the characteristic time it takes to deform.

    The interpretation stating that "the more accurately you want to measure the energy of a system, the more time it takes to measure" was shown to be wrong by Aharonov and Bohm in http://cos.cumt.edu.cn/jpkc/dxwl/zl/zl1/Physical%20Review%20Classics/quantum/019.pdf" [Broken]
    Last edited by a moderator: May 3, 2017
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