I hope people are still reading this thread because here’s something I’ve always wondered about Bose-Einstein Condensate: How does the atom know it’s stopped? It’s only stopped relative to the table top on which the experiment is being peformed. It’s still rotating around the earth rotating around the sun and so on. If I was on an airplane zooming over the “stopped” atom, would I be able to observe the Bose-Einstein Condensate since the atom was not stopped relative to me? Or if the experiment was being performed on a moving train, would an observer standing still outside the train be able to observe the condensate?
If you’ve never seen anything colder than absolute zero you haven’t met my ex-wife.
Your ex-wife is easy, what the F— you complaning about?
Of COURSE it’s possible to reach absolute zero–just stop by your local movie theatre!
/bad joke
There is a sense in which parts of a system can get to temperatures below 0 K. That is, you can have two kinds of particles in a system, say electrons (the so-called “electron gas”) and nuclei (the part with practically all the mass) in a metal, and the two subsystems can have different temperatures. Then you have an average for the whole thing. It is important because other properties such as the diffusivity can be different for the two subsystems. There are situations where one of the subsystems can have a negative temperature.
Reference, IIRC: “Temperatures Very Low and Very High”, forget author, published by Dover.
Here is a link to some stuff about Bose-Einstein Condensates;
http://www.colorado.edu/physics/2000/bec/index.html
some interesting educational games to play concerned with low temperature physics
Having lost this link somebody kindly retrieved it for me…
Thank you!
SF worldbuilding at
http://www.orionsarm.com/main.html