TY - GEN AU - Ovsienko, V. AU - Tabachnikov, S. TI - Projective differential geometry old and new: from the Schwarzian derivative to the cohomology of diffeomorphism groups SN - 9780511543142 U1 - 516.36 PY - 2005/// CY - Cambridge PB - Cambridge University Press KW - Projective differential geometry KW - Mathematics KW - Geometry KW - Schwarzian derivative KW - Topology KW - Algebra N1 - Includes index and references N2 - Ideas of projective geometry keep reappearing in seemingly unrelated fields of mathematics. The authors' main goal in this 2005 book is to emphasize connections between classical projective differential geometry and contemporary mathematics and mathematical physics. They also give results and proofs of classic theorems. Exercises play a prominent role: historical and cultural comments set the basic notions in a broader context. The book opens by discussing the Schwarzian derivative and its connection to the Virasoro algebra. One-dimensional projective differential geometry features strongly. Related topics include differential operators, the cohomology of the group of diffeomorphisms of the circle, and the classical four-vertex theorem. The classical theory of projective hypersurfaces is surveyed and related to some very recent results and conjectures. A final chapter considers various versions of multi-dimensional Schwarzian derivative. In sum, here is a rapid route for graduate students and researchers to the frontiers of current research in this evergreen subject. https://www.cambridge.org/core/books/projective-differential-geometry-old-and-new/25BE15C0126E8A1D8F5EC90827C7704B#fndtn-information ER -