Constant shift in MPS shift-and-invert algo

[ray-l]

Hi miles,

You probably have seen it and working on a solution (or that my new question was formulated badly and if that’s case I do apologize). But I’ve modified the code a bit to do the iterative linear solving, which for the moment does not work.

Just in case, the new question is linked here

Issues using linsolve (cont'd discussion)

Continuing the discussion from Constant shift in MPS shift-and-invert algo: I finally have time to come back to this problem. In short, I’m trying to variationally solve the following linear system: (H - \lambda) |\psi\rangle = |\phi\rangle Or that o--o--o- -o--o--o--o--o--o <psi| | | | | | | | | | | | o--o--o--o--o--o--o--o--o--o--o H | | | | | | | | | | | o--o--o--o--o--o--o--o--o--o--o H | | | | | | | | | | | o--o--o- …