The term temperature is used because they are literally using Boltzmann's distribution from statistical mechanics: e^(-H/T) where H is energy (Hamiltonian), T i

The term temperature is used because they are literally using Boltzmann's distribution from statistical mechanics: e^(-H/T) where H is energy (Hamiltonian), T is temperature. The probability they give to something of score H is just like in statistical mechanics, e^(-H/T) and they divide by the partition function (sum) similarly to normalize. (You might recognize it with beta=1/T there)