"How does a classical temperature form in the quantum world? An experiment at the Vienna University of Technology has directly observed the emergence and the spreading of a temperature in a quantum system. Remarkably, the quantum properties are lost, even though the quantum system is completely isolated and not connected to the outside world. The experimental results are being published in this week's issue of Nature Physics."-"In a way, the atomic cloud behaves like its own miniature universe. It is isolated from the environment, so its behavior is solely determined by its internal properties. Starting with a completely quantum mechanical state, the cloud looks "classical" after some time, even though it evolves according to the laws of quantum physics. That is why the experiment could not just help us to understand the behavior of large atom clouds, it could also help to explain, why the world that we experience every day looks so classical, even though it is governed by quantum laws."- Read more at: http://phys.org/news/2013-09-scientists-physics-classical-quantum-world.html#jCp