Hi,

I have a question about IQTensor following that of http://itensor.org/support/1126/superposed-states-with-iqtensor. Say I need to calculate O|psi> where O preserves some symmetry G but |psi> does not. That being said, |psi> can (as always) be decomposed into G eigenvectors such that each has a block structure.

My understanding is that the quantum number is taken care by the "boundary tensor". (correct me if I'm wrong.) That's to say, all tensors apart from the boundray one has divergence 0, while the divergence of the boundary one agrees with the quantum number. So a block-structured of |psi> is possible by a proper definition of the boundary one (i.e. a sum of tensors w/ different divergences) and it would still be efficient if I make use of the symmetry throughout. Is that correct?

Best,

Chengshu