Grassmann higher-order tensor renormalization group approach for two-dimensional strong-coupling QCD

We present a tensor-network approach for two-dimensional strong-coupling QCD with staggered quarks at nonzero chemical potential. After integrating out the gauge fields infinite coupling, partition function can be written as full contraction of tensor network consisting coupled local numeric and Grassmann tensors. To evaluate to compute observables, we develop higher-order renormalization group method, specifically tailored this model. During coarsening procedure, blocking adjacent tensors is performed analytically, total number variables in reduced by factor two each step. The coarse-site are truncated using singular value decompositions. method validated comparing function, chiral condensate baryon density computed exact analytical results on small lattices up volumes 4×4. For larger volumes, first mass volume, observe that symmetry not broken dynamically dimensions. also potential, which hint first-order phase transition.