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On algebraic classification of quasi-exactly solvable matrix models

R. Z. Zhdanov
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Abstract

We suggest a generalization of the Lie algebraic approach for constructing quasi-exactly solvable one-dimensional Schroedinger equations which is due to Shifman and Turbiner in order to include into consideration matrix models. This generalization is based on representations of Lie algebras by first-order matrix differential operators. We have classified inequivalent representations of the Lie algebras of the dimension up to three by first-order matrix differential operators in one variable. Next we describe invariant finite-dimensional subspaces of the representation spaces of the one-, two-dimensional Lie algebras and of the algebra sl(2,R). These results enable constructing multi-parameter families of first- and second-order quasi-exactly solvable models. In particular, we have obtained two classes of quasi-exactly solvable matrix Schroedinger equations.

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R. Z. Zhdanov. 1997-08-17. On algebraic classification of quasi-exactly solvable matrix models. https://doi.org/10.1088/0305-4470%2F30%2F24%2F034

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