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Third Law of Thermodynamics?

  1. Jan 4, 2005 #1
    Hello, I wonder if any of you would be kind enough to help a layman?
    I seem to remember a friend once told me that everything vibrates, and that nothing would exist if it didn't vibrate. For starters is this correct, or have I remembered incorrectly? Also, what is he talking about? Someone has told me that it could be the Third Law of Thermodynamics, but my friend was doing Quantum Mechanics, so perhaps it's something else? Does anyone have a clue what I could be looking for, and if so do you have the ability to explain it to an idiot?

    Sorry if I'm wasting your time, but I'm a Creative Music Technology student with a severe lack of knowledge in Physics, and I'd like to include some in an essay I'm currently writing.

    Thanks guys!

    Si
     
  2. jcsd
  3. Jan 4, 2005 #2

    cronxeh

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    I think you are looking for M Theory or look under String Theory.

    Basically its not proven yet but its a mathematically viable theory - if that makes any sense. The String Theorists claim that there are 11 dimensions and that on a really-really-really small scale there are vibrating strings of energy in all the matter. Now this cant (yet at least) be proven because the size of those strings in the smallest particles of matter is soooooooooo small that we cant physically see it (not yet -but its fail safe to say not in my lifetime)

    [​IMG]

    You should check out this site and watch all the videos there:
    http://www.pbs.org/wgbh/nova/elegant/program.html
     
  4. Jan 4, 2005 #3

    dextercioby

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    Max Planck improved the initial (1909) formulation of Walter Nernst of the III-rd principle of thermodynamics saying that at 0K,the entropy of any body is zero and similar,the thermodynamical coefficients go to zero as the temperature goes to 0.
    That doen't mean that for every system the energya and entropy are null at 0K.The QM harmonical oscillator is an example of a system that has nonzero zero-point energy.Even the entropy for a system of QM harmonic oscillators (a.k.a.the phononic system) is not zero.That's a quantum effect and it cannot be accounted for by the classical principle of Nernst-Planck.

    Daniel.
     
  5. Jan 4, 2005 #4

    Integral

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    The answer to this depends on what you mean by vibrating.

    Temperature is a measure of the kinetic energy of molecules, so every object which has a measurable temperature (this is one way of saying "everything") must have molecular motion. In a solid object, molecular motion is constrained to vibrations within the molecular structure. So in that sense all solid objects are vibrating.

    I would be harder to say the same thing about a gas.
     
    Last edited: Jan 4, 2005
  6. Jan 4, 2005 #5

    dextercioby

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    Nope,Integral,the atoms are vibrating within the molecule and they are looked upon as quantum vibrating systems similar to atoms in the nodes of a crytaline structure.

    Daniel.

    PS.I don't see why u say it is harder to say about gas.Just becuse those molcules are at the same time moving around?What's that got to do with vibrating atoms and Morse potential,for example...??

    EDIT: :rofl:
     
    Last edited: Jan 4, 2005
  7. Jan 4, 2005 #6

    Integral

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    Semantics.

    The reason that I say it is harder to describe a gas as "vibrating" is because I do not see the random motion of a gas molecule as a "vibration". To me a vibration is constrained to some form of periodic motion.

    Thus my opening statement, what do you mean by vibration.
     
    Last edited: Jan 4, 2005
  8. Jan 4, 2005 #7
    Thanks for the help guys, although I'm still finding it kinda hard to get my head round. I reckon I'm gonna go with String Theory, as I've already written about that in the essay, - I just wanted to make sure I hadn't grasped the wrong end of the stick. Besides, I like string theory, and it's a lot easier to understand being that it's speculation.

    Thanks again!

    Si
     
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