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Someone please help me understanding the quantum mechanics

  1. Dec 19, 2014 #1
    Hi, sorry, don't know where to post this question. I want to learn quantum mechanics and will someone please discuss with me the points like photoelectric effect, quanta, wave particle duality etc?
  2. jcsd
  3. Dec 19, 2014 #2


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    Gold Member

    You can start with the first few chapters of Eisberg's fundamentals of modern physics or Weidner and sells' Elementary modern physics.
  4. Dec 19, 2014 #3
    Thanks for the reply:)
    Actually I want to discuss the few basic topics with someone so that I can clear my concepts about them. The photoelectric effect, black body radiation, wave particle duality, Bohr atomic model etc.
  5. Dec 19, 2014 #4


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    Gold Member

    Well, you should say what is not clear for you so that people can explain and clarify it.
  6. Dec 19, 2014 #5
    in UV catastrophe, I can't understand clearly that what was the problem and how Planck solve it?
    UV catastrophe was that as scientists observed colour, temperature relationship in case of a perfect black body, they expected the curve of intensity against wavelength to shift to UV side with high intensity and infinite energy,why???
    and the experimental results didn't agreed with theoretical one. Planck solve this problem by considering that when an em wave is absorbed or radiated, it's energy is quantized. No, EM can be absorbed or radiated in fractions. But how this solved the problem?
  7. Dec 19, 2014 #6


    Staff: Mentor

    All right.

    Lets take it one step at a time.

    Exactly what isn't clear in the following:

    Classical statistical mechanics predicted a clearly unphysical result for a black body:
    'According to classical electromagnetism, the number of electromagnetic modes in a 3-dimensional cavity, per unit frequency, is proportional to the square of the frequency. This therefore implies that the radiated power per unit frequency should follow the Rayleigh–Jeans law, and be proportional to frequency squared. Thus, both the power at a given frequency and the total radiated power is unlimited as higher and higher frequencies are considered: this is clearly unphysical as the total radiated power of a cavity is not observed to be infinite, a point that was made independently by Einstein and by Lord Rayleigh and Sir James Jeans in the year 1905.'

    What Plank did, by assuming the cavity could only absorb and emit radiation in discreet units the problem was solved - and actually matched experiment if a certain value was chosen for those units.

  8. Dec 19, 2014 #7


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    Science Advisor

    Braam Gaasbeek has a good introductory text to start learning quantum mechanics. Everything looks great except for the last chapter on philosophy, which I think is wrong. Philosophy in quantum mechanics is very important, and for that I recommend either Landau and Lifshitz's or Steven Weinberg's quantum mechanics texts.

    An Introductory Course on Quantum Mechanics
    Bram Gaasbeek
  9. Dec 19, 2014 #8


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    Staff: Mentor

    Post your questions, then. That's the sort of thing this forum is for! :D

    It's to your advantage to post your questions publicly instead of trying to do it via a one-on-one conversation with someone via private messages. First, you'll get answers more quickly because you don't have to wait for one particular person to be available. Second, if there are errors in an answer, other people can correct them. Third, the collective knowledge of a group of people is greater than the knowledge of any single person.

    Finally, the public discussion is a useful resource for everyone else, now and in the future.

    However, please ask only one starting question per thread (or a very few closely related questions). Keep each thread focused on one topic. If you ask ten questions all at once in a single post, inevitably people will focus on only a few of them, and the rest will be ignored. Also, things become confusing when people try to discuss two or three or more things in parallel in the same thread.
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