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arXiv · 1704.06966

Renormalization Analysis for Degenerate Ground States

David Hasler·Markus Lange
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Abstract

We consider a Hamilton operator which describes a finite dimensional quantum mechanical system with degenerate eigenvalues coupled to a field of relativistic bosons. We show that the ground state projection and the ground state energy are analytic functions of the coupling constant in a cone with apex at the origin, provided a mild infrared assumption holds. To show the result operator theoretic renormalization is used and extended to degenerate situations.

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David Hasler, Markus Lange. 2017-04-23. Renormalization Analysis for Degenerate Ground States. https://doi.org/10.1016/j.jfa.2018.03.005

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