PCFormat Forum Archive

I wasn't certain whether I should post this in the "discussions" forum, as I am no physicist, and therefore do not think that I qualify to discuss the matter on which I am posting. I am therefore present it as news that may be of interest.

Nature.com wrote: It may sound less likely than hell freezing over, but physicists have created an atomic gas with a sub-absolute-zero temperature for the first time1. Their technique opens the door to generating negative-Kelvin materials and new quantum devices, and it could even help to solve a cosmological mystery.

More here

Go home physics, you are drunk...

o/t There is a science vs science fiction thread. I think this might be better suited to that thread.

And here I was thinking StarPheonix was the only thing lower than absolute zero that I know of

hamin_aus wrote:And here I was thinking StarPheonix was the only thing lower than absolute zero that I know of

Actually, there is still nothing lower than absolute zero.

Negative temperature on the kelvin scale is not colder than absolute zero; rather, the system's thermodynamic temperature can be of a negative quantity on the kelvin scale, and such a system is hotter than any system with a positive temperature in the sense that if negative-temperature and positive-temperature systems come in contact, heat flows from the negative to the positive system.

Here's why: temperature is defined as the relationship between energy and entropy. Most systems familiar to us cannot achieve a negative temperature because adding energy always increases their entropy; however, some systems (such as the one linked in the original post) have a maximum amount of energy that they can hold, and the system's entropy actually decreases as the energy limit is approached, and consequently the system's temperature becomes negative even though more energy is added. This is only attainable in quasi-equilibrium systems though, and is a strictly quantum phenomenon.

The negative temperature article on Wikipedia is surprisingly well-written (though it could be sourced better) for those interested in continued reading.

hamin_aus wrote:And here I was thinking StarPheonix was the only thing lower than absolute zero that I know of

Huggles.

Remind me to buy you a drink when I visit Australia.

For some odd reason the dragonball z power level thing comes into effect. Something like 1 = 1 punch, 9000 = 2 punches and over 9000 (billions) = 2 1/2 punches.

Here's a more comprehensive explanation of negative temperature, with the intended audience being people of lesser intelligence (read: every idiot on this forum).

Oh that is brilliant! I really enjoyed that. I am the right kind of idiot for that article.

Ron2K wrote:Here's a more comprehensive explanation of negative temperature

TL;DR - I'm here to troll, not learn!

But Jammy - you missed the best part. Making those dots fly around when you heat them is just the best - and when you add gravity into the mix - why it is positively orgasmic. You have no idea what you just missed!

Tribble wrote:...why it is positively orgasmic. You have no idea what you just missed!

Oh?

Yes?