Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Woldemar Voigt (2 September 1850 13 December 1919) was a German physicist, who taught at the Georg August University of Göttingen. He was born in Leipzig, and died in Göttingen. He was a student of Franz Ernst Neumann. He worked on crystal physics, thermodynamics and electro-optics. His main work was the Lehrbuch der Kristallphysik (textbook on crystal physics), first published in 1910. He discovered the Voigt effect in 1898. The word tensor in its current meaning was introduced by him in 1899. Voigt profile and Voigt notation are named after him. He was also an amateur musician and became known as a Bach expert.