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Generators of Invariants of Two $4 \times 4$ Matrices

Vesselin Drensky·Liliya Sadikova
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Abstract

Over a field of characteristic 0, the algebra of invariants of several $n\times n$ matrices under simultaneous conjugation by $GL_n$ is generated by traces of products of generic matrices. In this paper we have found, in terms of representation theory of $GL_2$, a minimal set of generators of the algebra of invariants of two $4\times 4$ matrices. The proof is purely combinatorial and involves computer calculations with standard functions of Maple.

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Vesselin Drensky, Liliya Sadikova. 2006-03-23. Generators of Invariants of Two $4 \times 4$ Matrices. https://arxiv.org/abs/math/0503146

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