To envision moving down the temperature scale into the realm of extreme cold, a good place to start is inside an industrial freezer. Around -18°C (0°F) is uncomfortable, but can be tolerated with warm clothing. Now turn your attention to the -60°C (-76°F) temperatures experienced by explorers during the Antarctic winter. And for extreme cold, consider the universe itself at -270°C.
However, you might be surprised to learn that the coldest place in the universe is not in space, but in many university physics departments. Here, over the past few decades, researchers have devised ways to approach the lowest possible temperature, absolute zero. Along the way, strange states of matter flowed uphill, suspending chemical reactions and entering new realms where designer materials could be assembled.
But now, we are entering a new phase in overcoming the cold by building the ultimate cooling technology, the quantum refrigerator. Things get even weirder when you turn on one of these ultimate cooling devices, heat reverses and temperature by itself means nothing.
The question of what it means to cool something has been around for thousands of years.Invented by the Greek philosopher Parmenides in 450 BC freegidum primum, an imaginary substance that is as cold as possible and can imbue other objects with coldness. 1664, then…