Ludwig Eduard Boltzmann.

Ludwig Eduard Boltzmann was the son of an Austrian state civil servant in the tax (internal revenue) department who died when Ludwig was fifteen years old. Ludwig studied at the Gymnasium in Linz, then moved to the University of Vienna, where he worked under Josef Stefan and Josef Loschmidt, receiving his doctorate when he was twenty-two years old. He moved into a position at the university and remained in academia for his entire career, rising as one did in the German university of the time from fee-supported lecturer to full professor. He became world-renowned as both teacher and researcher. Early in his career, Boltzmann produced experimental work in physics. In 1872, stimulated by James Clerk Maxwell's writings on electromagnetic theory; he studied dielectrics (insulators) with the intention of confirming Maxwell's technical prediction about the index of refraction of substances. He confirmed this prediction for both solids and gases. Boltzmann also confirmed that the speed of light varies in different directions in an anisotropic crystal (one with different symmetries on the x, y, and z axes). Boltzmann also published work on diamagnetism (the property of some substances, placed in a magnetic field, to become polarized in a direction that causes them to be repelled by the field) and on electromagnetic radiation. Later, he would renew his interest in electromagnetic theory, but not in laboratory experimentation. Boltzmann's reputation rests not on his publications in experimental physics but on his deep and penetrating mathematical analyses of physical phenomena, particularly those of molecules in a gas. INSET: Ludwig Eduard Boltzmann.