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Science

Another New State of Matter 13

llamalicious writes: "And you thought a Nobel Prize for the discovery of Bose-Einstein Condensates was nifty, SciAm's reporting that scientists are taking this new discovery one step further, and have once more proven that we don't really know anything about quantum physics. This new state is being called a patterned fluid, which could supposedly move the field of quantum computing ahead."
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Another New State of Matter

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  • That really cool (Score:3, Interesting)

    by TheGonzoKid ( 544822 ) <bpmatt1NO@SPAMcs.com> on Friday January 04, 2002 @10:24PM (#2789212) Homepage
    That's really cool just a few billionths of a degree above zero. I was always fascinated by quantum effects on super cooled liquids. Like that one experiment where water climbs out of the glass. I forget who it was that said, "If you think you understand Quantum Physics you don't"

  • by dragons_flight ( 515217 ) on Friday January 04, 2002 @11:54PM (#2789488) Homepage
    Reading the article and looking at the group's website [mpq.mpg.de], this doesn't seem all that special. In fact, unless I'm misinterpreting the result, it seems that you could build a Mott insulator with any kind of supercold gas. The real accomplishment was using a Bose-Einstein condensate to very easily construct an arrangement of atoms that would otherwise be technologically very hard. That they did it by means of a quantum phase transition (adjusting the parameters of the potential to produce a qualitative different wave function) is cool, but not exactly new.

    It's a neat hack, and I can imagine uses for being able to turn a BEC on and off at will, as well as for atomic arrays, but it just doesn't grab me as being all that radical. I would question calling it a new state of matter. More like a unusual way to make a very special kind of gas. Of course, I might just be missing something.
    • by dabacon ( 221175 ) on Saturday January 05, 2002 @12:57AM (#2789614) Homepage
      The real accomplishment was using a Bose-Einstein condesate to very easily construct and arrangement of atoms that would otherwise be technologically very hard

      Yep. While, as mentioned, you could do this with any supercold gas, the important point is that one should be able to use this to create uniformly populated optical lattices. This would be great for doing things like [hype mode on]building a quantum computer![hype mode off]

      Also neat is that this looks like a nice clean system for studying a quantum phase transition, but calling it a new state of matter is a bit odd. As far as I know, the observation of a Mott Insulator is nothing new...though in the context of supercold atomic systems this is probably new.

      Interestingly, when I searched Google for Mott Insulator, this experiment was the first to come up! Wow.

      Dabacon
    • If I understand the Nature summary correctly, the patterned fluid is analagous to a Mott insulator... I think what is considered to be new is the state that produces this effect - the article is careful to state that it is not a heat related phenomena, but one driven by the Heisenberg principle - that is the optical system doesn't heat the fluid up to produce a standing wave - the wave is a result of a more fundamental principle....

      Of course, it has been a long time since I slept through quantum mechanics, so I've probably missed just as much, if not more than you.... :-)

      • Yeah, that was what I read it as too. I know just a little about Mott insulators, but from what I know, this isn't a Mott insulator. All they're saying is that this is the kind of thing that happends in an MI, but for much different reasons. Instead of the wave being produced by the heat introduced, it's because of the inherent quantum fluctuations. That's like saying that since Coulomb's law looks just like the theory of gravity, that Coulomb didn't do anything special. (Or maybe it's not, I was never good at analogies...)
  • State of Matter? (Score:2, Insightful)

    by scott_oooo ( 546761 )
    Anyone know of a good difinition of a "State of Matter"? I think it is just one of those buzzwords some of the press used to grab attention for a science story.

    This certainly isn't a new phase of matter (like solid/liqud/gas etc) because I believe the thermodynamic definitions of phase changes involve how the heat capacity (or enthalpy) changes with temperature. This change in property of the BE gas is due to changing the LASER settings, not the temperature.
    • Re:State of Matter? (Score:2, Informative)

      by lines ( 410893 )
      If you plot temperature (degrees C, for example) vs heat added (Joules, calories, etc), you'll see that during phase changes, the temperature stays constant until all of the matter has changed to the new phase. For example, during the change from solid to liquid, all the heat goes to the phase change (the heat of fusion) and not to changes in temperature. I Am Not A Chemist/Physicist, but to me this constitutes a good starting point to the definition of phase changes and states of matter.

      hobbes
      • Yes, that's the way it works for the normal three, but I don't know that you can extend that definition to some of these new "states of matter". You can't exactly say that if you heated a BEC (Bose-Einstein Condensate) up, the energy would go into turning it into a solid, can you? (It wouldn't, it would sublimate (?) into a gas again, but that's not the point.) But that doesn't mean that it's not a new state of matter, (necessarily) it just means that the old definition can't be applied.

If Machiavelli were a hacker, he'd have worked for the CSSG. -- Phil Lapsley

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