5 Outlook We tried on the one hand several expressions and possible real valued functions for ψ for this approach and on the other hand piecewise defined wave functions including a Gauss function in area 1 and 3 and a polynomial in area 2 but neither the variation of the real and the imaginary part nor of the absolute value yield satisfying results for the non-interacting density. The fact that we are able to reproduce the densities with such an ansatz for c = 0, that is for the real case, implies that the complexness of the system is responsible for the non-applicability of this particular variational approach. 62
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