When I was studying physics at school as a late teenager I was told that outer-space was cold- very cold in fact it was as cold as it gets. And my physics text books told me that scientists knew that temperature and that temperature was -273 deg. Centigrade. Now to be strictly accurate that temperature is -273.15 deg. Celsius or is that -273.16 deg. (some confusion around freezing point of water and triple point of water). But then of course when I went to university I was told that even deepest darkest space was not at absolute zero it was a couple of degrees above absolute zero because of background microwave radiation. But then does space have a temperature at all. After all it is a near perfect vacuum – does a vacuum have a temperature? But one thing we can be sure of – nothing can be colder than absolute zero. At least on this one point all scientists are agreed – thank goodness the science (of absolute zero) is settled. There is a satisfying consensus, not 97% of scientists, not 98% of scientists but 100% of scientists agree. Phew, how comforting to be surrounded by people who agree with your point of view.

Oh darn – now some pesky meddling sceptic, denier scientists have come along and crashed the party. What’s this about quantum gases and sub absolute zero temperatures. Who let that lot in?

I shall finish on a famous, and very apt, quote by Albert Einstein:-