Negative Temperature: Understanding What Happens Below Absolute Zero

Thanks!

Now I've got some more esoteric terms to use when I'm explaining how my "over-unity" motors work, after all "Zero point" and "Neodymium" are getting a bit old hat.

As if our plates weren't already spilling into the next county with trying to understand what happens above absolute zero, they pile this on? Crikey, it's hard enough finding my way around Chinatown! And where are my car keys? And why no quality research anymore on far more pressing issues? Issues like "Where do lost socks go, really?" And "How do small tools get lost only to surface again years later in triplicate?" And "How does silicone cement always seem to know where you're holding the rag and instantly materialize there?" Deep issues. Practical issues. Don't these guys even care?

You know, somewhere there is a universe of lonely, single socks wondering "Where did the people go? Where did my mate go? Why are those car keys staring at me?"

Exactly.

Heartbreaking, really.

My wife and I still cant agree where cold begins!

You are obviously married.

The small nutdriver sets end up in your ceiling smelling like vomit.

Full-blown Antigravity or simple Levitation? Or something else? Something far more esoteric?

Surely this phenom could be harnessed for the Common Good? Say, as a deterrent to CR4's endless litany of bus-bar*-sizing queries (some days there are so many you'd think it was DDOS attack). Or "What's the difference between a Star and a Delta connection? Does it work with DC and, Oh, btw I'm designing that nuclear power plant right behind your house?"

Your thoughts?

-----

* The only one I've ever seen was owned by Willie Nelson.

The real issue is one of definitions. Absolute Zero is still Absolute Zero, even if it has shifted conceptually to -5degK, or whatever.

What's the limit on high temperature?

The Planck Scale. Somewhat as an aside, extremely high temps are more conveniently expressed in units of electron-volts, ie, MeV, Gev, Tev, etc., rather than in degrees (of either kind). The Large Hadron Collider - a 14 TeV device - simulates conditions a few fractions of a second after the Big Bang and, as temps go, that's pretty damn hot. Still, it is not even close to how high temps can go, in theory.

Energy has a corresponding wavelength, of course, as well as an equivalent mass. As the wavelength approaches one Planck Length - about a trillion trillion times smaller than a proton - the equivalent mass-energy approaches the point where the whole shootin' match is likely to collapse into a microscopic black hole and, at that point, all bets are off.

Not infinite, but damn close.

The Germans stated the obvious: Higher energy levels were more occupied than lower ones.

In a ruby slab, when optically pumped by a flash of light, the same thing happen, stably too. But, it is at room temperature, where something might start dropping to lower levels, starting a laser cascade. Do the same thing very close to absolute 0deg., and constraints might prevent the same thing to happen, maintaining an inverted population at different energy levels. Similar, if a bit more complicated with semiconductor devices.

Add to that, that the expression of the temperature close to absolute 0, is so difficult as nearly meaningless.

The achievement is quite respectable. But let's simply stick to the obvious: the population of different energy levels are the reverse of the customary, nonexcited system. That's that.

Quantum Theory states that not everyone can occupy the Ground State - even at Absolute Zero - and so we have to get a little nit picky about what, exactly, is meant by 'Absolute Zero' - if it has any meaning at all.

As they say in the car adverts, "Certain Exclusions Apply."