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arXiv:1102.2861

An algebraically independent generating set of the algebra of local unitary invariants

Péter Vrana

Published Feb 14, 2011• 0 citations
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Abstract

We show that the inverse limit of the graded algebras of local unitary invariant polynomials of finite dimensional k-partite quantum systems is free, and give an algebraically independent generating set. The number of degree 2d invariants in the generating set is equal to the number of conjugacy classes of index d subgroups of a free group on k-1 generators.

DOI
10.48550/arxiv.1102.2861

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We show that the inverse limit of the graded algebras of local unitary invariant polynomials of finite dimensional k-partite quantum systems is free, and give an algebraically independent generating set. The number of degree 2d invariants in the generating set is equal to the number of conjugacy classes of index d subgroups of a free group on k-1 generators.
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