Temperature in this sense no longer has anything to do with kinetic energy. A quantum system at absolute zero would simply be in its ground state, which is perf

Temperature in this sense no longer has anything to do with kinetic energy. A quantum system at absolute zero would simply be in its ground state, which is perfectly possible. In open space you only run into problems that there's not a particularly clear minimum. You do run into some problems with quantum fluctuations which may or may not randomly add energy to the system, I guess that's what this new result is about.