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Science

Scientists Set New Coldest Temperature Record 56

Posted by michael from the wear-your-mittens dept.
one_who_uses_unix writes "Scientists recently successfully cooled a gas to the coldest temperature ever recorded ABC News reports. This is good news for proponents of basic research (read non-applied) which has seen shrinking budgets over the past few decades, and for overclockers hoping to squeeze 1 more cycle out of their CPUs."
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Scientists Set New Coldest Temperature Record More

Scientists Set New Coldest Temperature Record

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  • So what happens if they ever hit absolute zero anyway?

    Will electrons fall out of orbit and cause atoms to collapse, thus creating a super dense cluster of subatomic particles?

    What effect would that have on the other atoms in the area? Could that cause a chain reaction that results in a black hole?

    I really hope I'm missing something, but that seems like the only logical outcome I can see.

    Can someone explain why I'm being over paranoid?

    • Comment removed (Score:5, Informative)

      by account_deleted ( 4530225 ) on Friday September 12, 2003 @09:41AM (#6942314)
      Comment removed based on user account deletion
      • It's not possible to hit absolute zero because of something called Heisenberg uncertainty principle.

        Absolute zero is then the atoms are not moving at all. It would be trivial then to know the position and speed at the same time, which is not possible.

        • Re:Low temperatures scare me (Score:1, Insightful)

          by Anonymous Coward
          It is quite likely that Heisenburg doesn't apply. When you look at extreme conditions you sometimes discover things about the universe you cound't see otherwise. Look at Newton's "Laws" regarding motion. When you look at things accelerating to extremely high speeds these laws turn out to be very wrong.
          They do these sort of things to try to disprove laws, or rather amend them to more accurately represent the universe.

      • Re:Low temperatures scare me (Score:5, Informative)

        by QuantumFTL ( 197300 ) * on Friday September 12, 2003 @12:53PM (#6944465)
        The chances are that they'll never hit absolute zero

        You're more right than you know. According to current quantum mechanics (which has been tested inside and out), the Heizenberg uncertainty principle states that the more you know about the velocity of a partical, the less you can know about its position, etc. In other words, the uncertainties must multiply together to be greater than plank's constant divided by 2PI. As temperature approaches absolute zero, the uncertainty in momentum (which is a functional of thermal energy at that point, which is proportional to temperature) decreases. This causes the uncertainty in posiition to drastically increase.

        Anyways at absolute zero this would mean the uncertainty in position would become infinite, in other words the position of the particle would be completely undefined. This is not possible so thus Absolute Zero is unattainable, even in theory.

        Disclaimer: I'm still working on my degree, and I was in a hurry writing this. Please correct me if you can :)
        • Why couldn't the particle just kind of phase out of reality and simultaniously exist everywhere at once, Heart-of-Gold style? Or maybe be moving in some other dimension thet we can't measure? Does Heisenburg's principle apply universally or is it only a 4 dimension thing?

        • Re:Low temperatures scare me (Score:1, Insightful)

          by Anonymous Coward
          Not sure but was wondering wouldn't this be a kind of exception to Heizenberg since absolute zero is the state of no movement then it would seem you would lose the uncertainty in location because that wasn't changing.
          • Not sure but was wondering wouldn't this be a kind of exception to Heizenberg since absolute zero is the state of no movement then it would seem you would lose the uncertainty in location because that wasn't changing.

            Actually as much as you might think this... it's not! In fact, even situations where you surely would think the uncertainty principle doesn't apply, it turns out it does!

            In an "empty space", you would think energy was zero. However, the uncertainty principle applies to all conjugate qua
          • wouldn't this be a kind of exception to Heizenberg since absolute zero is the state of no movement then it would seem you would lose the uncertainty in location

            No, you can't reach zero.

            A crucial but difficult to grasp part of it is that Heisenberg's uncertainty is NOT a measurement failure. The precise value can't be meausered because it does not exist.

            It's sort of like trying to measure the distance between Earth and Mars to the exact inch. Different parts of the Earth and different parts of Mars are d
          • Of course not. It takes energy to measure it, so it'd be raised above absolute zero and of course you agree that the principle applies there.
        • I always thought of this ass the particle getting larger: I thought a bose-einstein condensate was when the particles in a gas started overlapping with each other.

          An interesting side-effect would be that the size of the chamber limits the temperature. Perhaps someone with access to the constants involved could calculate what size (ie delta x) 9 nanokelvin represents?
        • My disclaimer is that all I've got is a programming job and an AS in computer-aided drafting, but here goes:

          Is absolute zero really an unreachable limit because of uncertainty? Or is it like the example in a previous Slashdot article where Apollo never passes the tortoise, because he must first close half the distance, then half the remaining distance, then half that distance, etc... and never actually passes the turtle.

          And what if we're dealing with non-quantum masses? I don't know where any particular
          • Apollo never passes the tortoise

            And yet he obviously does in a real experiment. I guess thats what the absolute zero experiments are about; there's no point in having a theory if you don't test it. If a lab really were to reach absolute zero, that would totally destroy the basis of quantum physics.
          • Is absolute zero really an unreachable limit because of uncertainty? Or is it like the example in a previous Slashdot article where Apollo never passes the tortoise, because he must first close half the distance, then half the remaining distance, then half that distance, etc... and never actually passes the turtle.

            Firstly, I believe that's Zeno, not Apollo. Secondly, no, it's nothing like that. Look at the formula:

            Um*Up >= Hbar

            The uncertainty of the momentum (Mass*velocity) times the uncertaint

          • Re:Low temperatures scare me (Score:4, Informative)

            by Alsee ( 515537 ) on Saturday September 13, 2003 @08:22AM (#6951257) Homepage
            Is absolute zero really an unreachable limit

            Yes, and there have been experiments that have demonstrated this is a way.

            Quantum mecanics says that everything (including energy) comes in unit size packets. The unit size is called a Planck unit. You can only add energy to a particle or subtract energy from a particle a full Planck at a time. Now here's the catch - if you look at how much energy a particle has it always has a "point five" on the end. A particle can have 1.5 Plancks of energy, 8.5 Plancks of energy, or a billion and a half Plancks of energy. As you try to take energy out eventually you get down to 0.5 Planks of energy and you are stuck. You can only take out a full Planck at a time.

            I'll explain one of the experiments they did that demonstrates this. Imagine you lie on the ground to the left of a flat table and randomly toss ping-pong balls up at it. The ping-pong balls have random energy. Any ping-pong ball you throw too slowly will fall back down without reaching the table top, it will fall back down and stay on the left. Any ping-pong ball you throw fast will reach the table top and bounce along and eventually fall off the right side. If you throw it real high it will make big bounces along the table-top and it will come down the right side falling really fast. Throw it slower and it will make little bounces. If you throw ping-pong ball *just barely* fast enough to reach the edge of the table top it will roll across the table top with zero up/down bounce and it will come off the right edge with zero falling speed. (It may be moving to the right very fast, but we are just looking at the up/down speed)

            Scientist did something like this, but instead of big fat ping-pong balls they used neutrons. They "tossed" them randomly up at the edge of a flat plate and the neutrons bounced along and fell off the right edge. They then studied the neutrons falling off the right and looked at their minimum speed:

            The researchers report seeing a minimum (quantum) energy of 1.4 picoelectron volts (1.4 x 10-12 eV), which corresponds to a vertical velocity of 1.7 cm/sec.

            NONE of the neutrons came off the right edge with zero up/down speed. They were ALL bounced along and came off going atleast 1.7 cm per second.

            In scientific terms gravity is really really weak. Almost infinitly weaker than the other forces. Since gravity is so weak and a single neutron is so tiny they "magnify" the size of a single a Planck. One Planck unit of gravitational energy for a single neutron on Earth is about 3.4 cm per second. That means you can only change the up/down speed of a neutron by 3.4 cm/sec at a time. If a neutron is going up at 5.1 cm/sec gravity will pull down and the speed will JUMP by 3.4 cm/sec. It will skip from an up speed of 5.1 to an up speed of 1.7 (5.1 - 3.4 = 1.7) Then gravity keeps pulling down and you get another 3.4 jump in speed. It will skil from UP 1.7 cm/sec to going DOWN 1.7 cm/sec. (1.7 - 3.4 = negative 1.7)

            The neutron is always going up or down by at least 1.7 cm per second. It "teleports" right past zero without ever being zero.

            We never notice this in the "real world" because even the tinyest spec of dust is made of many millions of neutrons, half of them going up at hundreds of miles per hour and half going down at hundreds of miles per hour. They constantly bounce off of each other reversing direction a million times per second.

            That's why you can never hit absolute zero, quantum mechanics says the energy always ends up least one-half of a step off of zero.

            -
        • It's been years since I last opened a QM book, but I'll take a shot at this.

          Heisenberg's principle is not related to temperature. In fact, introductory QM courses usually ignore temperature (unless there is some mention of kT, you're at 0 K). This does not mean that the particles are immobile, just that they are in the fundamental state (no excitations); the uncertainty principle still holds. Of course, if you go to finite temperature your system can jump to an excited state an the uncertainty Dp Dx will

      • I always wondered about that. If the speed of light is so impossible, then how does light manage to go that fast?

    • Re:Low temperatures scare me (Score:4, Interesting)

      by 4of12 ( 97621 ) on Friday September 12, 2003 @10:09AM (#6942653) Homepage Journal

      Will electrons fall out of orbit and cause atoms to collapse

      Probably not, since most electrons live in their lowest allowable quantum state already, unless you're in a plasma.

      This really is an achievement, getting down to a nanokelvin.

      Our experience is using degrees or Kelvin to measure temperature and people tend not to be impressed that the coldest temperature went from a microK to a nanoK, because the upper end of the scale is millions and billions of degrees - so who cares about changing temperature from 10^-3 K to 10^-9 K?

      It was explained once to me that if the temperature scale were redefined using a logarithmic mapping (T_new = log(T_old)) that we'd be a lot more impressed with low temperatures and with the asympototically unreachable nature of "absolute zero" that sits at a finite and seemingly reachable value.

      • Re:Low temperatures scare me (Score:5, Interesting)

        by Alsee ( 515537 ) on Saturday September 13, 2003 @10:21AM (#6951661) Homepage
        logarithmic mapping

        Good idea. Here is a logarithmic (base 10) scale:

        Core of a supernova: 9.2
        Highest man made (1996): 8.7
        Core of the Sun: 7.2
        Surface of the Sun: 3.75
        Water boils: 2.57
        Human body temperature: 2.49
        Room temperature: 2.47
        Water freezes: 2.44
        Liquid oxygen: 1.95
        Dark side of the moon: 1.95
        Pluto: 1.68
        Deepest depths of space: 0.44 (Cosmic microwave background)
        Boomerang Nebula, [nasa.gov] coldest natural place in the universe: roughly zero
        Coldest man made (1995): -6.77
        Coldest man made (today): -9.3

        Man made (-9.3) is as much colder than coldest place in the natural universe (zero) as the core of a supernova (9.2) is hotter than the coldest place in the natural universe.

        -
    • What effect would that have on the other atoms in the area? Could that cause a chain reaction that results in a black hole?

      Not a black hole, the earth and anything that falls into its orbit will become one giant Bose-Einstein condensate [nist.gov]. :J
    • Don't worry. 1. As some of the other posts point out, too, absolute zero cannot be reached, according to the Third Fundamental Law of Thermodynamics. And even if you do (well, in 'contradiction' to the sentence before, you can, if you restrict your ambition to only certain degrees of freedom, like, bringing all vibrations of the atoms' center-of-mass motion to a halt), there is still the quantum zero-point fluctuation. 2. These nanokelvin experiments usually only cool down a few thousand atoms. Or, to be

  • Overclockers ? (Score:5, Insightful)

    by $exyNerdie ( 683214 ) on Friday September 12, 2003 @09:43AM (#6942340) Homepage Journal

    and for overclockers hoping to squeeze 1 more cycle out of their CPUs

    How does such a low temperature help in overclocking ?
    Article says:
    "At less than 1 nanokelvin, the atoms screech to a crawl, moving only one inch every 30 seconds. "

    Does anyone else also think that "overclocking" was mentioned just to get attention of /. editors ??

    • Re:Overclockers ? (Score:4, Funny)

      by one_who_uses_unix ( 68992 ) <(glen.wiley) (at) (gmail.com)> on Friday September 12, 2003 @10:20AM (#6942745) Homepage
      As a matter of fact, you are correct, I mentioned overclockers to get their attention. This was a blatant attempt to introduce humor into the otherwise serene and serious atmosphere maintained on /. If I could retract the sentence and replace it with....

      "No facetious observations regarding the relationship between extremely low temperatures and overclocking are permitted."

      I have a few comments on this observation that should server to vindicate me in the mind of those who might be concerned by the gratuitous use of technology buzzwords:

      1. What is wrong with getting /. editor's attention?
      2. Smile - you will find it is healthy.
      3. Made ya look.
    • "Does anyone else also think that "overclocking" was mentioned just to get attention of /. editors ??"

      No. The rest of us know that it was meant to be humorous.

  • Amazing... (Score:5, Interesting)

    by feidaykin ( 158035 ) on Friday September 12, 2003 @10:00AM (#6942541) Journal
    The last time a new record was set, a scientist was quoted saying that if there was a colder temperature anywhere in the universe, it was in the lab of an alien civilization.

    I would imagine his opinion would remain unchanged by this new record...

    This is the coldest known place in the universe: http://antwrp.gsfc.nasa.gov/apod/ap030220.html [nasa.gov]

  • scientists report that SCO verbal FUD apparently does not obey the laws of physics.
  • "In this house we will obey the laws of thermal dynamics."

  • by combining the hearts of Bill Gates, John Ashcroft, and Hillary Clinton.

  • Overclocking? (Score:2, Redundant)

    by Mad Quacker ( 3327 )
    "and for overclockers hoping to squeeze 1 more cycle out of their CPUs."

    Sorry to burst your bubble, but chips stop working completely at temperatures that cold. In fact chips for extraterrestrial use often need heaters to bring them up to operational temperatures.

    Absolute zero is absolute because it means zero atomic movement; no electron movement; no Quake frames per second.

  • Somebody's GOT to say it ... (Score:3, Funny)

    by ninewands ( 105734 ) on Friday September 12, 2003 @11:59AM (#6943848)
    even though I'm SURE to get modded into oblivion ...

    this is SO COOL!


  • Coolest thing in the Universe revealed [newscientist.com]

    A tiny cloud of sodium atoms has been chilled to within half a billionth of a degree of absolute zero
  • The article states that "in deep space where gases are 3 degrees above absolute zero, or about -454 degrees Fahrenheit." which puts absolute zero at -457F.
    Then it states "Absolute zero, or -460 degrees..."
    And my science book places it at -459. I know there is a difference between a Kelvin degree and a Fahrenheit one, but which is it?
    And, with no other base of reference, how can they no that their temperature detectors are accurate at such low temps?
    • Deep space is 3 degrees C above absolute zero (or about 3 K). Courtesy of google:

      3 Kelvin = -454.27 degrees Fahrenheit

      0 Kelvin = -459.67 degrees Fahrenheit

      Note: the temp of deep space isn't exactly 3 K, so don't put too much faith in those digits after the decimal point.

    • C=5(F-32)/9
      K=C-273

      -uso.
  • The MicroKelvin Lab [ufl.edu] at the University of Florida does research in the 100uK range. They have the largest ultra-low temperature lab in the world (there's another one like it at Cornell).
  • My ex-wife's heart.

    Me ? Bitter ? Nah !!
  • As you might know, the Nobel Institute publishes posters each year explaning the achievements of the Nobel laureates for the general public.

    So if you want to know about ultracold gasses, have a look at these links:

    * Doppler cooling, or: how to use a laser not to hup stuff but to cool it: Nobel prize 1997 [nobel.se]

    * the Bose-Einstein condensate: a weird state of matter that is formed by bosonic atoms at really ultralow temperature: Nobel prize 2001 [nobel.se]

    * not that cool but still quite cool: suprafluid helium flow

  • Pac's dead body because I KILLED HIM!

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