Reconstruction of full-space quantum Hamiltonian from its effective, energy-dependent model-space projection

Miloslav Znojil

doi:10.1016/j.physleta.2025.130816

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arXiv · 2506.22854

Reconstruction of full-space quantum Hamiltonian from its effective, energy-dependent model-space projection

Miloslav Znojil

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Abstract

Reconstruction of a full-space quantum Hamiltonian from its effective Feshbach's model-space avatar is shown feasible. In a preparatory step the information carried by the effective Hamiltonian is compactified using a linear algebraic operation (matrix inversion). A ``universal'' coupled set of polynomial algebraic equations it then obtained. In a few simplest special cases their solution is given and discussed.

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Miloslav Znojil. 2025-06-28. Reconstruction of full-space quantum Hamiltonian from its effective, energy-dependent model-space projection. https://doi.org/10.1016/j.physleta.2025.130816

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