# Potter, Wielandt, and Drazin on the matrix equation $AB=\omega BA$, with some new answers to old questions

@article{Holtz2005PotterWA, title={Potter, Wielandt, and Drazin on the matrix equation \$AB=\omega BA\$, with some new answers to old questions}, author={Olga Holtz and Volker Mehrmann and Hans Schneider}, journal={arXiv: Rings and Algebras}, year={2005} }

In this partly historical and partly research oriented note, we display a page of an unpublished mathematical diary of Helmut Wielandt's for 1951.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 $AB = \omega BA$, 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.

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