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The Hubbard chain: Lieb-Wu equations and norm of the eigenfunctions

F. Göhmann·V. E. Korepin
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Abstract

We argue that the square of the norm of the Hubbard wave function is proportional to the determinant of a matrix, which is obtained by linearization of the Lieb-Wu equations around a solution. This means that in the vicinity of a solution the Lieb-Wu equations are non-degenerate, if the corresponding wave function is non-zero. We further derive an action that generates the Lieb-Wu equations and express our determinant formula for the square of the norm in terms of the Hessian determinant of this action.

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F. Göhmann, V. E. Korepin. 1999-08-07. The Hubbard chain: Lieb-Wu equations and norm of the eigenfunctions. https://doi.org/10.1016/s0375-9601(99)00774-4

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