Polynomially Isometric Matrices in Low Dimensions

@article{Brooks2021PolynomiallyIM,
  title={Polynomially Isometric Matrices in Low Dimensions},
  author={Cara D. Brooks and Alberto A. Condori and Nicholas Seguin},
  journal={The American Mathematical Monthly},
  year={2021},
  volume={128},
  pages={513 - 524}
}
Abstract Given two d × d matrices, say A and B, when do p(A) and p(B) have the same “size” for every polynomial p? In this article, we provide definitive results in the cases d = 2 and d = 3 when the notion of size used is the spectral norm. 

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