fastdla.generators.z2lgt_hva.z2lgt_u1_projector

fastdla.generators.z2lgt_hva.z2lgt_u1_projector(num_fermions, charge)

Construct the charge conservation law projector for the Z2 LGT model.

The U1 charge of the L2 LGT is

\[Q = \frac{1}{N_s} \sum_{n=0}^{N_s-1} Z_n.\]

For a fermion number \(N_f\) and an overall charge \(q \in [-2N_f,...,2N_f]\), we have a \({}_{2N_f} C_(N_f+q/2)\)-dimensional eigenspace.