The spectral theorem in quaternions
An exposition of the spectral theory of normal matrices with quaternion entries is presented. The principal objective of the paper is to set down detailed proofs of the quaternionic spectral theorem in both the matrix-theoretic and abstract formulations. A second objective of the paper is to unite and to reflect upon some related issues that are crucial to the study of linear algebra over the quaternions: spectra, modules, and inner products. A few applications of the spectral theorem, such as the polar and singular value decompositions, are also explained.
scientific article; zbMATH DE number 1978107
scientific article