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  1. Standard member sonhouse
    Fast and Curious
    07 Jan '13 11:09
    http://phys.org/news/2013-01-gas-temperature-absolute.html
  2. 07 Jan '13 21:40 / 1 edit
    Originally posted by sonhouse
    http://phys.org/news/2013-01-gas-temperature-absolute.html
    Is this strictly speaking an exception, to the third law of thermodynamics?
    If so, I assume that this exception is in some sense 'trivial'? else I don't understand why we have always been taught that going below absolute zero is impossible.
  3. 08 Jan '13 02:17
    Originally posted by humy
    Is this strictly speaking an exception, to the third law of thermodynamics?
    If so, I assume that this exception is in some sense 'trivial'? else I don't understand why we have always been taught that going below absolute zero is impossible.
    It's a quirk of the definition of temperature.

    You can get negative absolute temperatures which correspond to systems with the
    inverse of the standard Boltzmann distribution of particle velocities.

    So technically speaking if something has a negative absolute temperature that makes it
    hotter than something that is infinitely hot...

    This article explains it better.

    http://phys.org/news/2013-01-atoms-negative-absolute-temperature-hottest.html#nRlv


    And no there is no violating the 2nd law here. move along...
  4. Standard member sasquatch672
    Don't Like It Leave
    08 Jan '13 03:41
    Originally posted by googlefudge
    It's a quirk of the definition of temperature.

    You can get negative absolute temperatures which correspond to systems with the
    inverse of the standard Boltzmann distribution of particle velocities.

    So technically speaking if something has a negative absolute temperature that makes it
    hotter than something that is infinitely hot...

    This artic ...[text shortened]... perature-hottest.html#nRlv


    And no there is no violating the 2nd law here. move along...
    That didn't explain a damn thing better.
  5. 08 Jan '13 11:29
    Originally posted by sasquatch672
    That didn't explain a damn thing better.
    The article I linked explained it quite neatly.

    If it doesn't make sense to you then you possibly just need to study more physics.
  6. 08 Jan '13 13:18 / 7 edits
    Originally posted by googlefudge
    It's a quirk of the definition of temperature.

    You can get negative absolute temperatures which correspond to systems with the
    inverse of the standard Boltzmann distribution of particle velocities.

    So technically speaking if something has a negative absolute temperature that makes it
    hotter than something that is infinitely hot...

    This artic ...[text shortened]... perature-hottest.html#nRlv


    And no there is no violating the 2nd law here. move along...
    oh right, now I get it.
    So it is NOT strictly speaking going below absolute zero and going below absolute zero is strictly impossible just as I have been always taught. That's a relief.

    And no there is no violating the 2nd law here. move along...


    -and, also, there is no violating the 3rd law here
  7. 09 Jan '13 20:29
    Originally posted by humy
    oh right, now I get it.
    So it is NOT strictly speaking going below absolute zero and going below absolute zero is strictly impossible just as I have been always taught. That's a relief.

    And no there is no violating the [b]2nd law here. move along...


    -and, also, there is no violating the 3rd law here [/b]
    You got it. :-)

    A negative absolute temperature corresponds to a temperature above +infinity...

    And not a temperature below Abs Zero.

    Although given the absurdity of having a temperature above +infinity, let alone denoting
    it as a negative temperature, probably suggests that a better definition of temperature
    might be in order.

    It's probably best to think of negative absolute temperatures as being like imaginary numbers.
    And not part of the normal number line.
  8. Standard member Soothfast
    0,1,1,2,3,5,8,13,21,
    10 Jan '13 20:44
    Originally posted by googlefudge
    You got it. :-)

    A negative absolute temperature corresponds to a temperature above +infinity...
    Well that's just bonkers. Trust physicists to take a perfectly logical temperature scale and totally frack it up to make headlines.