L22.4 Identical particles and exchange degeneracy

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  • เผยแพร่เมื่อ 5 ก.ย. 2024
  • MIT 8.06 Quantum Physics III, Spring 2018
    Instructor: Barton Zwiebach
    View the complete course: ocw.mit.edu/8-...
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    L22.4 Identical particles and exchange degeneracy
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ความคิดเห็น • 12

  • @psiphixium3919
    @psiphixium3919 2 ปีที่แล้ว +2

    This is gold!

  • @satyamshukla381
    @satyamshukla381 3 ปีที่แล้ว +4

    Electron spin up and electron spin down state has same mass. Nucleon spin up and nucleon spin down state has different mass, why to call them same state. Why is there this difference?

    • @bilalhussein9730
      @bilalhussein9730 3 ปีที่แล้ว +3

      Isospin is an approximate symmetry. As you said the symmetry is broken by the nucleon mases and electromagnetism as the proton is charged while the neutron is not.
      What is meant by an approximate symmetry is that if we get results that are true assuming exact isospin symmetry, then the actual result in nature is the same thing up to percent-level corrections because of the smallness of the fine structure constant and the mass difference between up and down quarks divided by the QCD confinement scale. We can then use techniques like perturbation theory to solve for these corrections.

  • @Neo-Reloaded
    @Neo-Reloaded 2 ปีที่แล้ว +2

    Sir, I don't understand the isospin. Can you make a video about that?

    • @inonazizi7981
      @inonazizi7981 ปีที่แล้ว +1

      I'm also a little confused on the isospin

  • @bluedot6933
    @bluedot6933 ปีที่แล้ว +1

    no two things can be identical, there must be some property that distinguishes one from the other. if 2 things a and b have the same properties then those 2 things are in fact one thing.

    • @The_Don_Dial_100
      @The_Don_Dial_100 6 หลายเดือนก่อน

      😂 it's not philosophy its physics...
      😅 Don't Give unusual Hypothesis

    • @bluedot6933
      @bluedot6933 6 หลายเดือนก่อน

      for everything there must be a sufficient reason for why it is and not different. if identical particles existed then there would be no reason for one to be one and for another to be another. @@The_Don_Dial_100

  • @cikif
    @cikif 5 ปีที่แล้ว +3

    10:38 We *cannot* do the same

    • @nphuc
      @nphuc 4 ปีที่แล้ว +1

      "cannot" is a very important word in this situation.

  • @bruna.corcino
    @bruna.corcino 2 ปีที่แล้ว

    Dar um quadro branco pra esse homem. Todo sujo de pó de giz o pobri.

    • @hectorfreire4991
      @hectorfreire4991 วันที่ผ่านมา

      Chamar um professor do MIT de pobre é a melhor parte kkkkkk