Gruppentheorie und Quantenmechanik, or The Theory of Groups and Quantum Mechanics, is a textbook written by Hermann Weyl about the mathematical study of symmetry, group theory, and how to apply it to quantum physics. Weyl expanded on ideas he published in a 1927 paper,[1] basing the text on lectures he gave at ETH Zurich during the 1927–28 academic year.[2][3] The first edition was published in 1928; a second edition followed in 1931, which was translated into English by Howard P. Robertson.[4][5] Dover Publications issued a reprint of this translation in 1950.[6]
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