According to wikipedia :- " Formally, temperature is defined as the derivative of the internal energy with respect to the entropy." I always thought entropy is defined in terms of energy and temperature. IS this true that temperature is defined in terms of entropy and energy? According to it :- dS = dQ / T IS this somehow related to the fact that lowest temperature can only be zero as then entropy change will be zero I found all this connected but somehow cannot put them together. Is kelvin scale defined with the help of this equation???