Unfavourable temperature: Atoms past absolute zero could also be a brand new type of matter

A cloud of atoms with a temperature past absolute zero – which can also be bizarrely hotter than any constructive temperature possible – may very well be a mysterious new quantum state of matter.

Luca Donini on the College of Cambridge and his colleagues have put hundreds of potassium atoms into this seemingly paradoxical state of affairs by exactly manipulating their vitality ranges and quantum states. “Quantum mechanics allows you to do this, while classical thermodynamics would never allow it,” he says.

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