back to article Boffins create quantum gas with temperature BELOW absolute zero

Boffins at the Ludwig Maximilian University in Munich, Germany have literally turned the Kelvin scale on its head, having produced a quantum gas with a temperature below absolute zero. Ulrich Schneider and his colleagues created the subzero gas by arranging potassium atoms into a lattice using lasers and magnetic fields, then …

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  1. Anonymous Coward
    Anonymous Coward

    So they have negative Kinetic Energy?

    and therefore imaginary speed?

    1. Anonymous Coward
      Coat

      Re: So they have negative Kinetic Energy?

      No need to get complex…

      1. Anonymous Coward
        Anonymous Coward

        Re: So they have negative Kinetic Energy?

        Ah...

        http://en.wikipedia.org/wiki/Negative_temperature

        "negative temperature is a strictly quantum phenomenon"

        ... hence the mind-fuck

        1. Whitter
          Happy

          Re: So they have negative Kinetic Energy?

          First thing I thought on reading the article intro was "aren't population inversions in a laser in a negative temperature state?"

          I must get out more.

    2. amanfromMars 1 Silver badge

      Negative Kinetic Energy but Positive Virtual Power?*

      Methinks, therefore speedy imagination is a leading metadatabase consideration for Novel Mega Kinetic Energy Storages and Hot IP Stores.

      For those luscious tales of absolute power beyond earthly control .... Heavenly Trails which Follow Devilishly Good Deeds Done Devilishly Good :-)

      Is Kim Dotcom building a Virtually IntelAIgent Power System with Secure Anonymous Programmers Sharing Gathered Key Secrets? Or is that proprietary private information safe and secure in Novel Mega Storage facilities.

      Quite what those facilities can and will then do with secured information and advanced intelligence, is the stuff of pure and true legend.

      * The Great Military Dilemma .... Peaces Provide Perfect Virgin Power Platforms, and yet the Fooled play War in the Great Games Field.

      War is simple. Pick a tall tale and invade. Peace in worlds of endless bounty to enjoy and share appears to present an execution difficulty and identifies a virtual machine malfunction ... and an anomaly which shouldn't really be there. Is human intervention at fault and to blame?

      1. gazzton
        Thumb Up

        Re: Negative Kinetic Energy but Positive Virtual Power?*

        Weird and askew of the topic as usual but strangely poetic construction. Nice.

      2. Hooksie

        Re: Negative Kinetic Energy but Positive Virtual Power?*

        What in the fuck are you talking about? Is that some random word generator??

        1. John Arthur

          Re: Negative Kinetic Energy but Positive Virtual Power?*

          No, it's the man from mars!

    3. Stuart Elliott
      Coat

      Re: So they have negative Kinetic Energy?

      No, they have finally produced LUDICROUS SPEED.

      1. TRT Silver badge
        Headmaster

        Re: So they have negative Kinetic Energy?

        They appear to have created a quantum of unstable thought on the inside of my head from a considerable distance.

      2. Doctor_Wibble
        Coat

        Re: So they have negative Kinetic Energy?

        Heading in the right direction, but it really can't be Ludicrous, since that is part of a predictable progression.

        This is a strange scale-turns-back-on-itself thing so it must be the next along the scale, genuinely Faster Than Ludicrous, and yet slightly weird at the same time. You know what this means.

        A true FTL such as this could only ever be Plaid.

    4. nigel 15
      WTF?

      Re: So they have negative Kinetic Energy?

      You're quite right.

      By redefining absolute zero we have created something below absolute zero.

      Balls to 'em. What did they do for new year's 'eve?

  2. SDoradus

    T is related to the logarithm of available states

    For an isolated collection of atoms behaving as a gas one would be using the so-called "statistical mechanics" formalism for temperature.

    I was taught that temperature was related to the change in entropy with energy pumped into the system. You get negative temperature when there's a grossly unlikely set of occupied states. (Entropy of an isolated system is proportional to the logarithm of the available number of states). Much of the math assumes the system is at equilibrium. Apparently these atoms were not. So curious anomalies are possible.

    1. I. Aproveofitspendingonspecificprojects

      Re: T is related to the logarithm of available states

      What is the answer in double decker bus lanes?

  3. MondoMan
    Boffin

    Sci Am had a good article on this 35 years ago

    Scientific American

    Volume 239, Number 2, August, 1978

    "Negative Absolute Temperatures"

    1. Destroy All Monsters Silver badge

      Re: Sci Am had a good article on this 35 years ago

      Torrent, please.

      1. Dave 126 Silver badge

        Re: Sci Am had a good article on this 35 years ago

        Issues of Scientific American have a page in which they reproduce articles from 25, 50, and 75 years ago... so if you want to read the article mentioned above, all you have is wait until 2028 and buy a copy.

        Glad to be of service!

        1. Destroy All Monsters Silver badge
          Unhappy

          Re: Sci Am had a good article on this 35 years ago

          Well, a have SciAm subscription (okay, I admit they sometimes write bad stuff but their illustrations are the best) but even then their online archive is just 1993 to present....

          I AM WAY ABOVE FOURTEEN AND WHAT IS THIS?

          Even the IEEE has better archives.

        2. Dodgy Geezer Silver badge
          FAIL

          Re: Sci Am had a good article on this 35 years ago

          Actually, this was first done in 1951...

          So, not actually news then....

  4. frank ly

    "The temperature scale simply does not end at infinity,"

    Surely he means 'zero'? Or do they have other research going on that gets to negative values of temperature by heating something to infinity and beyond?

    1. richardcox13

      Re: "The temperature scale simply does not end at infinity,"

      > Or do they have other research going on that gets to negative values of temperature by heating something to infinity and beyond?

      That's exactly it.

      The Wikipedia article http://en.wikipedia.org/wiki/Negative_temperature has been cited as containing a good introduction.

      It is an effect in a quantum system so you need to forget your intuition.

      1. Destroy All Monsters Silver badge
        Pint

        Re: "The temperature scale simply does not end at infinity,"

        There seems to be no need to invoke THE QUANTUM. See SDoradus above.

    2. P. Lee
      Joke

      Re: "The temperature scale simply does not end at infinity,"

      Maybe he's using two's complement. You can keep adding until you go negative.

    3. Pascal Monett Silver badge

      Re: "do they have other research going on"

      Of course they do.

      At the Black Mesa facility.

      Crowbar mandatory.

      1. kwg06516

        Re: "At the Black Mesa facility."

        Ha Ha,

        Fat chance!

  5. Robert E A Harvey
    Stop

    nonsense

    Playing fast-and-loose with the definition of temperature with a few hundred potassium atoms balanced on individual laser beams is one thing. Making new and novel stable materials is a whole different bunch of subatomic phenomena.

    1. lglethal Silver badge
      Boffin

      Re: nonsense

      True, but it all has to start somewhere...

  6. John Smith 19 Gold badge
    Coat

    Pop. Sci headline "Scientists clock the thermometer of the Universe."

    Respect.

    Time to do the walk of shame.

  7. This post has been deleted by its author

  8. mIRCat
    Coat

    Very cool.

    Not really, but I'll grab my coat anyways.

  9. Martin Huizing
    Facepalm

    "below absolute zero"

    And I'm still here? Non-story, fellas...

    1. James Hughes 1

      Re: "below absolute zero"

      Heads....

  10. Schultz
    Boffin

    It all depends on how you define temperature

    Temperature is a meaningful concept when a system is in equilibrium. The authors of this work pull a fast one by putting the system out of equilibrium and looking at the 'temperature' before the system is equilibrated, hence they can produce this weird property of a negative temperature.

    Nice trick, but it's mostly a creative use of scientific language to sell some elaborate experiments to the broader public.

    1. Michael 31
      Thumb Up

      Re: It all depends on how you define temperature

      Exactly. Well Said. Thank You.

      Temperature only exists as a meaningful concept when a system of particles are at - or very close to - equilibrium.

      This experiment is like sticking all your furniture to the ceiling and saying "Hey! I have produced anti-gravity"!

      http://protonsforbreakfast.wordpress.com/2013/01/04/negative-temperatures-do-not-exist/

    2. Dave 126 Silver badge
      Happy

      Re: It all depends on how you define temperature

      >Nice trick, but it's mostly a creative use of scientific language to sell some elaborate experiments to the broader public.

      I think you've concisely defined New Scientist's MO. Good work, sir!

  11. Fred Flintstone Gold badge

    Well, that merely proves..

    .. that nothing is absolute.

    Well done - I love it when someone upends established thinking and thumbs his or her nose at tradition.

  12. John Smith 19 Gold badge
    Boffin

    Looking at the abstract

    It appears that they have produced a population inversion, like a laser before it fires.

    Except that being in a solid the energized atoms are at different levels above the ground state when they pull their trick, rather than the single one you need for a laser to work.

    I suspect SDoradus's description of temperature as it applies to a group of atoms is the correct way to look at this.

  13. Stratman

    When they "suddenly adjust the magnetic field...."

    .... what do they mean by 'suddenly'?

    1. Ole Juul

      Re: When they "suddenly adjust the magnetic field...."

      I was under the impression that "suddenly" only occurs when you're just walking along minding your own business and not paying attention. In this case however, we're talking science, so it will have a more strict definition - could we perhaps talk of multiple suddenlies, or even 1/2 suddenly?

    2. JeffUK
      Pint

      Re: When they "suddenly adjust the magnetic field...."

      Suddenly, in this context, is defined as 1 millionth of a perfect pint (The time it takes for a pint of Guinness to settle acceptably)

  14. Gordo Rex
    Holmes

    Understement of the year nominee (already!)

    "That might seem counterintuitive at first;"

    This is in opposition to all other quantum effects which are intuitively obvious?

  15. T. F. M. Reader

    What's new?

    There is nothing particularly novel, sinister, or, indeed, special in negative temperatures - they correspond to higher energy states being more populated than low energy ones. Such systems can exist while isolated. Isolation is, of course, difficult to achieve or maintain in an experiment.

    For chuckles, I recall (French physicist of Russian/Jewish origin) Anatole Abragam's "model of the Soviet Union" as a system with negative temperature (a notion - in physics - to which Abragam himself contributed significantly). The main point was that as long as such a system is isolated, as the USSR was before Gorby, it can maintain the state. Once brought into contact with a thermostat (outside world) it would transition into a normal, positive temperature state. Formally though, it needs to pass through a state with infinite temperature, i.e., absolute chaos. Anyone remembers what it looked like in the 90ies? ;-)

  16. Anonymous Coward
    Anonymous Coward

    Anti gravity

    So does this mean I might eventually get the anti grav pack I always wanted since reading about them in Henlien's Starship Troopers when I was a kid?

    1. John Smith 19 Gold badge
      Unhappy

      Re: Anti gravity

      "So does this mean I might eventually get the anti grav pack I always wanted since reading about them in Henlien's Starship Troopers when I was a kid?"

      The GI's did not use antigravity.

      And no you don't get one because of this research.

  17. FatGerman
    Mushroom

    My brain just melted

    Why do I persist in reading stuff like this on a Saturday?

    1. amanfromMars 1 Silver badge

      Re: My brain just melted

      Crikey, FatGerman, imagine the billions with nothing new to entertain and occupy their thinking. How be their day decided and who delivers fate and destiny and programming to the masses?

  18. John Savard

    Indeed

    I remember that one of my first assignments when taking a Scientific Russian course in 1972 was to translate an article which noted that systems at negative absolute temperatures were the basis of lasers. I assume, though, that the research is new because it involves negative absolute temperatures - hotter than infinity, not colder than zero - in a different kind of quantum system, one where they weren't previously produced.

  19. stragen001
    Boffin

    My Brain Hurts

    I hate quantum mechanics.......

  20. Anonymous Coward
    Mushroom

    Reminds me of the study...

    That assumed on the radiographical analasis (typing in dark here with a no letter keyboard) that the atmosphere would in fact not be set globally on fire, due to atmospheric testing of the Mighty A Bomb.

    However in plunging below absolute zero, if THAT ever escapes from the laboratory, it could devastate the entire planet, by flash freezing the entire surface.......

  21. John Savard

    A Simple Explanation

    Think of a plastic cylinder containing marbles.

    If it just sits there, they're all at the bottom.

    If you shake it back and forth a small distance, the marbles will bounce up and down. The faster you shake it, the more often a marble will hit the top of the cylinder.

    You could work out a mathematical formula for how much it's being shook randomly based on the logarithm of the ratio between the density of marbles at the top and bottom. As the amount of random shaking approaches infinity, the number of marbles at the top and the bottom would approach equality.

    Now jerk the whole cylinder down quickly instead of shaking it. The marbles will go to the top. So the formula will give a negative logarithm, but that means more than infinite shaking instead of less than no shaking.

  22. Anonymous Coward
    Anonymous Coward

    Explain like I'm five...

    ...as I understood things, zero kelvin is when shit stops moving. Your molecules stay where they're put.. Surely even if your molecules are wobbling left -> right -> left instead of the customary right -> left -> right; the temperature is still above zero kelvin because shit is moving?

    1. Mark Scott

      Re: Explain like I'm five...

      Try this:

      http://www.amazon.co.uk/How-Teach-Quantum-Physics-Your/dp/1851687793.

      Woof!

  23. Chris Walton
    Coat

    Alternative explanation

    "The temperature scale simply does not end at infinity," Schneider explains, "but jumps to negative values instead."

    This reminds me of how a signed integer is stored, for example in an 8 bit system values 0-127 are positive and values 128-254 are treated as negative - I knew it, we are all in the matrix!

  24. Paper
    Paris Hilton

    So correct me if I'm wrong...

    From what little I get of science, is this experiment like putting a cup of hot water at one end of the bath, measuring the other end and then claiming that adding hot water actually decreased the temperature?

  25. Boyd Crow
    Megaphone

    But it is COLD

    Absolute zero is COLD, it's just that this quantum "trick" doesn't actually make it colder in terms of kinetic energy. Absolute temperature is a measure of both kinetic energy and entropy. Magnetically locking the atoms into a tighter lattice reduces the entropy further, even though the kinetic energy cannot be further reduced. So, if we could just get the science writers to use "absolute temperature" when talking about this story, all the confusion would be magically reduced to a lower level of comprehensive entropy.

  26. Anonymous Coward
    Flame

    Quantum gas?

    Hah! Give me a Taco Supreme and an order of nachos and I'll show you some quantum gas.

  27. JDX Gold badge

    What a story to read at 8am on a Monday Morning!

    It's all a trickery about how temperature is defined - it has little to do with heat around absolute zero - but my head still hurts.

  28. Robert Helpmann??
    Childcatcher

    But What is That in Hiltons?

    I had to do a quick look-up of the Reg official units of measurements to remind myself that we should be discussing this in terms of Hiltons (Hn). Using the defined UOM as 10°K per 1Hn for conversion with 0Hn pegged at 293K*, we can derive the "few** billionths of a Kelvin below absolute zero" as being somewhere around -29.300000003Hn

    * For calibration purposes, zero on the Register temperature scale is the temperature at which a talented ex-jailbird heiress can be expected to be fully dressed in at least one layer of clothing. (Underpants optional, obviously.) This is set at 293K, or 20°C. Accordingly, what the rest of the world might call 0°C, we shall refer to as -2 Hiltons (Hn).

    ** Few I propose this be officially adopted by El Reg as the awkwardness constant.

  29. tony

    So when are we getting cryo-arithmetic engines?

  30. The Grump
    Pint

    You know they're not lying when...

    a police callbox materializes out of nowhere, and a very worried looking bloke runs out of it, and tells the researchers that their invention will destroy the universe, and maybe a couple other parallel universes that are parallel parked next to ours.

    Me ? I'm popping off for that perfect pint of Guinness someone mentioned earlier.

  31. John Smith 19 Gold badge
    Unhappy

    I sort of get it.

    No it's gone.

    Sorry.

    Something about temperature ->measure of entropy rise in a substance.

    But if most atoms already excited outside ground state more energy could make them collapse like a laser but in terms of physical movement of whole atoms rather than electrons.

    No. It's gone. Really thought I had it. <sigh>

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