Baez always makes interesting reading. At the end of the abstract there is the arxiv-bait "inverse temperature is imaginary time", which relates to Wick Rotati

Baez always makes interesting reading. At the end of the abstract there is the arxiv-bait "inverse temperature is imaginary time", which relates to Wick Rotation and his work on quantropy a few years ago: http://jakobschwichtenberg.com/wick-rotation-action-formalism/ http://jakobschwichtenberg.com/wick-rotation-action-formalis... https://johncarlosbaez.wordpress.com/2011/12/22/quantropy/ https://johncarlosbaez.wordpress.com/2011/12/22/quantropy/ https://arxiv.org/abs/1311.0813 https://arxiv.org/abs/1311.0813 TL;DR if Boltzmann says thermodynamic states occur in proportion to exp(-E/kT), Feynman says paths in the quantum state space occur with weight exp(-S/i hbar), and action S ~ Et, then there is some analogy, ignoring constants (k,hbar,c) that goes like: (1/T) ~ it then we vaguely remember that the fourth dimension of spacetime is not time itself, but ict: https://en.wikipedia.org/wiki/Wick_rotation https://en.wikipedia.org/wiki/Wick_rotation