Sebastian Stumper

Hi Matthew, did you find time to look at the issue? I just realized that, even if I only define 'Ostr', but set the system size to L=16 instead of 8, there are similar problems in Version 3. Best, Sebastian

Dear all, I have trouble computing the dynamics of some correlation functions (Bose-Hubbard, Spin-1 Heisenberg), depending on whether some other Observables are defined or not. Attached is an example script for Quench dynamics in a Bose-Hubbard model, using the TDVP. The Observable 'Ostr' is only computed correctly, if the line myObservables.AddObservable('corr',['dn','dn'],'nn') is commented out. It seems that this problem did not exist in version 2.1, but in the newer versions 3 and 3.1. Could...

Hello, I am trying to simulate a Spin-1 chain similar to the Bilinear Biquadratic model, of which there is a pre-built implementation in open MPS. Because it seems that it is not possible to use the symmetry of conserved total Spin \sum Sz with the Bilinear Biquadratic model, I rewrote the Hamiltonian solely in terms of Sz, S+ and S-, which are compatible with the symmetry (see attachment). I am interested in some quantities involving Sx, such as the string correlation function Sxexp(i pi \sum Sx)Sx...

Hello, I have a peculiar problem which seems to depend on the types of observables defined in my code. So far I ran static simulations defining site, corr and string observables in bosonic and spin-chains and everything worked. After adding MPO observables, directly copied from the example codes in https://openmps.sourceforge.io/pyautodoc/obsterms.html?highlight=addobservable#obsterms my Observables, e.g. in a spin chain, are myObservables = mps.Observables(Operators) myObservables.AddObservable('site',...