than any other mathematician, Varićak devoted himself to the development of the non-euclidean style [of relativity], unfolding Minkowski's image of velocity-vector relations in hyperbolic space, and recapitulating a variety of results in terms of hyperbolic functions. The use of hyperbolic trigonometry was shown by Varićak to entail significant notational advantages. For example, he relayed the interpretation put forth by Hergloz and Klein of the Lorentz transformation as a displacement in hyperbolic space, and indicated simple expressions for proper time and the aberration of light in terms of a hyperbolic argument. Varićak is also known as a high school teacher of Milutin Milanković and of Mileva Marić, the first wife of Einstein, and as a university instructor of Đuro Kurepa. Varićak made scholarly contributions on the life and work of Ruđer Bošković (1711–1787) These are listed in the biography of Kurepa (1965) cited below. Of special interest for the history of relativity is that Varićak also edited and published a little-known 1755 paper of Boscovich in Latin entitled "On absolute motion – if it is possible to distinguish it from relative motion" ("Of Space and Time"). Varićak said that the paper "contains many remarkably clear and radical ideas regarding the relativity of space, time and motion." (Quoted from Silberstein: Theory of Relativity, 1912, footnote p. 38) Although having a Serbian origin and being an Orthodox and later Greek Catholic, he disputed and dismissed the thesis that Ruđer Bošković was a Serb. He was a member of the Yugoslav Academy of Sciences and Arts, the Czech Academy of Sciences, the Serbian Academy of Sciences and Arts, the Croatian Society for Natural Science, and the Yugoslav Mathematical Society. Publications Varićak, V. (1908) "Zur nichteuklidischen analytischen Geometrie", Proceedings of the International Congress of Mathematicians, Bd. II, SS. 213–26. Wikisource translation: Application of Lobachevskian Geometry in the Theory of Relativity Wikisource translation: The Theory of Relativity and Lobachevskian Geometry Wikisource translation: The Reflection of Light at Moving Mirrors Wikisource translation: On Ehrenfest's Paradox Wikisource translation: On the Non-Euclidean Interpretation of the Theory of Relativity Varićak, V.(1924) Darstellung der Relativitatstheorie im drei=dimensionalen Lobatschefskijschen Raume, Zagreb (Narodni Novini); English translation (2007) Relativity in three dimensional Lobachevski Space, A.F. Kracklauer translator , at Amazon.com. A complete list of Varićak's publications on all subjects is given in the following paper: Notes External links "Vladimir Varićak" at the University of Zagreb Croatian mathematicians Croatian physicists Yugoslav mathematicians Yugoslav scientists Austro-Hungarian