Ooh, relativistic thermodynamics. Here’s a good quote from the article:

Ooh, relativistic thermodynamics. Here’s a good quote from the article:

“…an interesting fact about temperature. Although we typically measure it in units of degrees or kelvins, according to basic physical laws it really has units of inverse seconds—a rate. […] The time it takes a quantum system to change discernibly is inversely proportional to the spread of its energy, which is proportional to temperature for systems in thermal equilibrium. Thus time is inversely related to temperature, and vice versa.”

and even better:

“Specifically, Rovelli argued that temperature is the rate at which systems change their internal state. Air at room temperature, for example, changes state 3 trillion times per second as the molecules feverishly reshuffle themselves. In this spirit, Rovelli proposed defining equilibrium as a condition not of uniform temperature, but of a common rate of changing state. The Tolman-Ehrenfest effect then makes perfect sense. By warping time, gravity mucks with the time standard by which rates are measured. As you climb a mountain, time passes more quickly and rates slow down. The rate at which a gas changes state—and thus its temperature—thus decreases even though the gas molecules are as feverish as ever.”

Originally shared by George Musser

On Carlo Rovelli’s “thermal-time” hypothesis and the zeroth law of thermodynamics, based on his talk at the recently concluded FQXi conference on the physics of information.