“…Recently, there has been a growing interest the critical behavior of statistical-physics models on curved surfaces-ranging from spin models, such as the ferromagnetic Ising model [1,2,3,4], the XY model [5,6], the Heisenberg model [7], the q-state clock models [8,9], to other traditional models, such as percolation [10], diffusion [11], etc. One reason for this interest is that many newly discovered soft materials (e.g., carbon nanotubes) show a negatively curved structure in the nanoscale [12].…”