tl;dr: The negative values described in that article are possible because a broader definition is used: > In statistical mechanics and thermodynamics, temperat

tl;dr: The negative values described in that article are possible because a broader definition is used: > In statistical mechanics and thermodynamics, temperature is defined as follows: > 1/temperature = change in entropy/change in energy > This definition of temperature can go from positive infinity to negative infinity. For context, the more common definition for absolute temperature is the average kinetic energy of the particles in the system, which of course can't be negative.