new scientist: “In computer science, people ask this question all the time: how long does it take to perform a computation?” says Oppenheim. “Just as a computing machine performs a computation, a cooling machine cools a system.” So, he and Masanes asked how long it takes to get cold. by Leah Crane
'Cooling can be thought of as a series of steps: heat is removed from the system and dumped into the surrounding environment again and again, and each time the system gets colder. How cold depends on how much work can be done to remove the heat and the size of the reservoir for dumping it.
'By applying mathematical techniques from quantum information theory, they proved that no real system will ever reach 0 kelvin: it would take an infinite number of steps.
'Getting close to absolute zero is possible, though, and Masanes and Oppenheim quantified the steps of cooling, setting speed limits for how cold a given system can get in finite time.'