2 7 D ec 2 00 5 Potter , Wielandt , and Drazin on the matrix equation AB = ωBA , with some new answers to old questions
نویسندگان
چکیده
In this partly historical and partly research oriented note, we display a page of an unpublished mathematical diary of Helmut Wielandt’s for 1951. There he gives a new proof of a theorem due to H. S. A. Potter on the matrix equation AB = ωBA, which is related to the q-binomial theorem, and asks some further questions, which we answer. We also describe results by M. P. Drazin and others on this equation.
منابع مشابه
Potter, Wielandt, and Drazin on the Matrix Equation AB = ωBA: New Answers to Old Questions
1. INTRODUCTION. The aim of this paper is to present a slice of the linear algebra of the 1950s and to give some answers to questions raised by Helmut Wielandt at that time. It was Wielandt's habit over many years to make notes on papers that interested him in what he called " diaries " (Tagebücher). These diaries were made available by his family after his death in February 2001 and are curren...
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