Dyson orbitals are mathematically meaningful, in the sense that they, unlike the DFT orbitals for instance, are actual observables of the wavefunction, instead of being "the other way around". They are defined as the overlap integral between the N-electron wavefunction and the (N-1)-electron wavefunction.

Suppose one tries to theoretically compute Dyson orbitals, using the FCC/FCI method for the computation of wavefunctions and using the mathematically complete basis set for both sub-computations. This results in an integral, over the whole space, of two infinite series.

And, in Fourier analysis, such integrals often lead to many mathematically rigorous cancellations(believe me, I'm literally a mathematics student), the "leftover parts" being much simplified.

My question now follows- does this "cancellation" occur for my specific case of FCC/FCI-Dyson orbitals as well?

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    $\begingroup$ It would be better if you describe how the cancellations work in Fourier analysis, since most people on this site are physicists and chemists that may not be so familiar with Fourier analysis. $\endgroup$
    – wzkchem5
    Nov 19, 2022 at 9:13