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On the eigenvalue problem for arbitrary odd elements of the Lie superalgebra gl(1|n) and applications

S. Lievens·N. I. Stoilova·J. Van der Jeugt
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Abstract

In a Wigner quantum mechanical model, with a solution in terms of the Lie superalgebra gl(1|n), one is faced with determining the eigenvalues and eigenvectors for an arbitrary self-adjoint odd element of gl(1|n) in any unitary irreducible representation W. We show that the eigenvalue problem can be solved by the decomposition of W with respect to the branching gl(1|n) --> gl(1|1) + gl(n-1). The eigenvector problem is much harder, since the Gel'fand-Zetlin basis of W is involved, and the explicit actions of gl(1|n) generators on this basis are fairly complicated. Using properties of the Gel'fand-Zetlin basis, we manage to present a solution for this problem as well. Our solution is illustrated for two special classes of unitary gl(1|n) representations: the so-called Fock representations and the ladder representations.

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S. Lievens, N. I. Stoilova, J. Van der Jeugt. 2007-01-05. On the eigenvalue problem for arbitrary odd elements of the Lie superalgebra gl(1|n) and applications. https://arxiv.org/abs/math-ph/0701013

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