"Negative Temperature" Achieved I was reading this article which says that scientists have recently achieved a "negative temperature" system, which apparently has a temperature which is "below absolute zero": http://arstechnica.com/science/2013/01/scientists-create-negative-temperature-system/ So this seems to get into some legalistic debates on what temperature actually is, and how "negative absolute temperature" is actually hotter than infinitely high temperature, etc. I'm still parsing through it, trying to understand. What are the practical applications of this, if any? Could it be possible to use this "negative temperature" to heat up things which are already intensely hot? Could it be possible to use this to cold down something which is already at absolute zero? Could we use this to cool electronic or laser components more efficiently? Could we use this to heat up D-T fuel pellets for fusion? Could we use it for anything practical?