Relatively Human — Season 1, Episode 11: The Invention of Disorder Carnot, Clausius, Boltzmann, and the Quantity Nobody Understood

Episode Summary: In 1824, a young French engineer named Sadi Carnot tried to find the absolute maximum efficiency of a steam engine. In doing so, he accidentally stumbled upon the most consequential constraint in all of physics. Decades later, Rudolf Clausius would formalize this constraint and give it a name: entropy. But while Clausius could measure entropy with thermometers and prove that it dictated the arrow of time, nobody could explain why it always increased.

Enter Ludwig Boltzmann. In 1877, Boltzmann made an audacious, cross-domain leap. He claimed that thermodynamic entropy was secretly about counting the microscopic arrangements of inv ...