# Implications of pinned occupation numbers for natural orbital expansions. II: rigorous derivation and extension to non-fermionic systems

@article{Maciek2019ImplicationsOP, title={Implications of pinned occupation numbers for natural orbital expansions. II: rigorous derivation and extension to non-fermionic systems}, author={Tomasz Maciążek and A. Sawicki and D. Gross and Alexandre Lopes and C. Schilling}, journal={arXiv: Quantum Physics}, year={2019} }

We have explained and comprehensively illustrated in Part I that the generalized Pauli constraints suggest a natural extension of the concept of active spaces. In the present Part II, we provide rigorous derivations of the theorems involved therein. This will offer in particular deeper insights into the underlying mathematical structure and will explain why the saturation of generalized Pauli constraints implies a specific simplified structure of the corresponding many-fermion quantum state… Expand

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