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arXiv · 2302.09892

Accuracy Tests of the Envelope Theory

Lorenzo Cimino·Cyrille Chevalier·Ethan Carlier·Joachim Viseur
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Abstract

The envelope theory is an easy-to-use approximation method to obtain eigensolutions for some quantum many-body systems, in particular in the domain of hadronic physics. Even if the solutions are reliable and an improvement procedure exists, the method can lack accuracy for some systems. In a previous work, two hypotheses were proposed to explain the low precision: the presence of a divergence in the potential or the lack of a variational character for peculiar interactions. In the present work, different systems are studied to test these hypotheses. These tests show that the presence of a divergence does indeed cause less accurate results, while the lack of a variational character reduces the impact of the improvement procedure.

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Lorenzo Cimino, Cyrille Chevalier, Ethan Carlier, Joachim Viseur. 2023-02-20. Accuracy Tests of the Envelope Theory. https://doi.org/10.1016/j.rinp.2024.107470

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