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I have difficulty understanding quantum physics

  1. Sep 28, 2014 #1
    Like I was reading Stephen Hawkings and while I found quantum physics interesting, I had trouble truly understand it. I mean I know it's the study of very small particles and stuff like you cannot predict where an electron is if the more you know its velocity but I had trouble understand the why of it?

    How can I make it intuitive?
     
  2. jcsd
  3. Sep 28, 2014 #2
    That would be heisenbergs uncertanty priciple that one can derive from the cauchy schwarz inequality. In addition quantum mechanics says that as long as the observables do not comute you can't measure the eigenvectors simultaneusly.
     
  4. Sep 28, 2014 #3
    (<A>^2<B>^2) > <[A,B]>*1/2
    or
    (<A>^2<B>^2) = <[A,B]>*1/2

    where [X,P]=-ih/2pi

    just substitute that in to the top equation and you get heisenbergs uncertanty priciple
     
  5. Sep 28, 2014 #4
    I'm not talking about the Uncertainty Principle. I'm just talking about the entire branch in general :/
     
  6. Sep 28, 2014 #5
    Sorry. QFT is not really intuitiv for example the hole stuff on entaglement of two spin systems. I would actually recommend you learn QFT first and then classical physics. If you need an Intro to quantum mechanics I would recommend Susskind , he covers the basics of harmonic oscillaotrs spina and the hole uncertanty. I don't quite understand what you mean but mabe this helped???
     
  7. Sep 28, 2014 #6

    ZapperZ

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    You might want to read this for my take on why you may not be equipped to "understand" QM

    https://www.physicsforums.com/threads/why-is-quantum-mechanics-so-difficult.765713/

    Zz.
     
  8. Sep 28, 2014 #7

    bhobba

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  9. Sep 28, 2014 #8
    Good luck, even Einstein needed it!
     
  10. Sep 28, 2014 #9

    mfb

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    That does not work. And the hard part about understanding quantum mechanics is not the physics of classical mechanics, it is our lack of intuition about quantum mechanics.
     
  11. Sep 28, 2014 #10
    How would one develope a classical intuition if one learnt QFT first?
     
  12. Sep 28, 2014 #11
    The article was good but I'm only 15 and didn't get the maths so I understood even less than usual.
     
  13. Sep 28, 2014 #12

    ZapperZ

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    And that is why your original question cannot be answered until you have the mastery of more advanced mathematics that one typically gets in college. At this stage, you are capable of only seeing the shadow of the animal, not the animal itself.

    Please consider using the Reply function for a particular post. It is difficult to figure out whom you are referring/replying to.

    Zz.
     
    Last edited: Sep 28, 2014
  14. Sep 28, 2014 #13
    Darn.
     
  15. Sep 28, 2014 #14

    mfb

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    By living in a macroscopic world. Even small children have the intuition I mean - objects have a specific place, speed, they do not vanish suddenly and so on. All those everyday experiences are not true in quantum mechanics, and that makes learning it hard.

    QFT has a lot of mathematics in addition - and you better learn that before (together with classical mechanics, and then quantum mechanics), otherwise you are completely lost in QFT.
     
  16. Sep 28, 2014 #15
    You're in good company. Einstein had trouble understanding it too! Well, actually, he understood it, but he didn't like what he understood :)
     
  17. Sep 29, 2014 #16

    TheDemx27

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    Last edited: Sep 29, 2014
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