On some extensions of the A-model

Rytis Jursenas

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arXiv · 1909.07078

On some extensions of the A-model

Rytis Jursenas

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Abstract

The A-model for finite rank singular perturbations of class $\mathfrak{H}_{-m-2}\smallsetminus\mathfrak{H}_{-m-1}$, $m\in\mathbb{N}$, is considered from the perspective of boundary relations. Assuming further that the Hilbert spaces $(\mathfrak{H}_n)_{n\in\mathbb{Z}}$ admit an orthogonal decomposition $\mathfrak{H}^-_n\oplus\mathfrak{H}^+_n$, with the corresponding projections satisfying $P^\pm_{n+1}\subseteq P^\pm_n$, nontrivial extensions in the A-model are constructed for the symmetric restrictions in the subspaces.

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Rytis Jursenas. 2019-09-16. On some extensions of the A-model. https://arxiv.org/abs/1909.07078

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