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 …
Methinks, therefore speedy imagination is a leading metadatabase consideration for Novel Mega Kinetic Energy Storages and Hot IP Stores.
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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?
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.
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.
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.
> 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.
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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.
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/
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.
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?
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? ;-)
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.
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.......
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.
...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?
"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!
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.
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.
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.
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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