Ludwig Boltzmann (1844-1906), an Austrian physicist famous for the invention of statistical mechanics. Boltzmann provided the framework for relating the microscopic properties of individual atoms and molecules to the macroscopic or bulk properties of materials that can be observed in every day life. Statistical mechanics also explains thermodynamic properties of bulk materials from the spectroscopic data of individual molecules. One of Boltzmann’s great insights was his finding that a macroscopic state is proportional to the logarithm of the number of microscopic states corresponding to it. He is famous for his formula for entropy (S): S = kB lnP where kB = 1.380658´10-23JK-1 (the Boltzmann constant), and P is the number of possible microscopic states which give the same thermodynamical state that a system may be in.
 Flamm, D., 1997. Ludwig Boltzmann – A Pioneer of Modern Physics. Paper presented at the XXth International Congress of History of Science, on July 25, 1997, in Liège, Belgium.
Ludwig Boltzmann Biography (University of Minnesota Morris)