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تسجيل مستخدم جديدSelf-Adjoint Extensions of Bipartite Hamiltonians
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We compute the deficiency spaces of operators of the form $H_A{hat{otimes}} I + I{hat{otimes}} H_B$, for symmetric $H_A$ and self-adjoint $H_B$. This enables us to construct self-adjoint extensions (if they exist) by means of von Neumanns theory. The structure of the deficiency spaces for this case was asserted already by Ibort, Marmo and Perez-Pardo, but only proven under the restriction of $H_B$ having discrete, non-degenerate spectrum.
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