Negative Temperatures are HOT - Sixty Symbols
Why Physics Stack Exchange recommends it
Physics Stack Exchange users link it when answering or asking about negative absolute temperatures, population inversion in lasers, and heat flow between negative and positive temperature systems.
Recommended by 3 people across 3 different months, 2013 to 2022.
What it is
Professor Philip Moriarty of the University of Nottingham explains how a system can have a negative absolute temperature and why such states are hotter than any positive temperature. The 13-minute Sixty Symbols video, made by Brady Haran, covers the entropy-based definition of temperature and the odd behavior of heat flow with negative-temperature systems.
What people said
Recommends user1966726 · 2013-10 · Physics Stack Exchange · on “Spontaneous conversion of heat into work at negative temperatures”
I stumbled on this video some time ago describing about the paper you are mentioning. [this video] Maybe, it might be of some use to you.
Recommends user108787 · 2016-11 · Physics Stack Exchange · on “Absolute temperature infinity”
Maybe, just maybe, this video might be related [this video] skip ahead for the first minute. Apologies if is not helpful to you. Also the link the QMechanic link, have you read it, what part do you not follow? Thanks
Recommends Joako · 2022-04 · Physics Stack Exchange · on “Doesn't the thermodynamic definition of temperature imply the existence of exotic systems with negative temperatures?”
In this video1 [this video] is explained how through entropy is possible to define a negative temperature to explain how laser light works, and in this video2 [LINK] is explained that is because of these negative temperatures why laser light could be focus on points that achieve higher temperatures than on the laser pointer emission, thing that will violate the 2nd law of thermodynamics in the case of natural light (due to etendue conservation).
Cites Waffle · 2013-05 · Physics Stack Exchange · on “Negative temperature and Absolute hot”
This [this video] video explains that heat at negative temperatures flows from the negative object to the normal object. If the temperature of the normal object is absolute hot, what happens with the heat? The heat can't be transferred to the absolute hot object, and it apparently does not flow in the other direction, so what happens to it?