New form of matter predicted by Einstein has temperature below absolute zero

[ack]

http://www.theregister.co.uk/2013/01/05/quantum_gas_below_absolute_zero/

 

[Steve Williams]

very interesting read Peter, thanks

 

[GaryProtein]

I must have missed something. . . . "Below absolute zero is HOTTER than the same system at any positive temperature?????"

I know advanced calculus has been my foible in physics, but WTF??

 

[Nightlord]

I must have missed something. . . . "Below absolute zero is HOTTER than the same system at any positive temperature?????"

I know advanced calculus has been my foible in physics, but WTF??

Normal 'hotness' is about particle movement, perhaps below absolute zero there is another mechanism in play ?

 

[ack]

Note that this doesn't mean the resulting system is actually cold, however. Nothing can be colder than absolute zero, which is a theoretical state at which particles have no energy at all. On the contrary, a system with a sub-zero absolute temperature is actually hotter than the same system at any positive temperature – a perverse result of how absolute temperature has been defined.

As we make more inroads into quantum physics we will be discovering more and more such paradoxes, which eventually will lead to redefining the status quo. On the macro scale, you may have seen Steve's videos of what happens when traveling at the speed of light, like everything looking warped, or being able to see your back when looking forward; BTW, there is an MIT computer game that shows this http://gamelab.mit.edu/games/a-slower-speed-of-light/

 

[garylkoh]

Hurts my head just to think of it.... adding energy results in a decrease of energy? The link to the full article didn't work for me, but they did not say how many degrees above absolute zero they started at before dropping to a few billionth of a degree below zero. I wonder how much energy it took, because the jump from near zero entropy to near infinite entropy would have to be massive.

 

[ack]

you will need a subscription to read the entire paper http://www.sciencemag.org/content/339/6115/52

 

[ack]

From Nature magazine's coverage on this http://www.nature.com/news/quantum-gas-goes-below-absolute-zero-1.12146

Another peculiarity of the sub-absolute-zero gas is that it mimics 'dark energy', the mysterious force that pushes the Universe to expand at an ever-faster rate against the inward pull of gravity. Schneider notes that the attractive atoms in the gas produced by the team also want to collapse inwards, but do not because the negative absolute temperature stabilises them. “It’s interesting that this weird feature pops up in the Universe and also in the lab,” he says. “This may be something that cosmologists should look at more closely.”