caa a22 4500 445855770 CHVBK 20180317145427.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s00026-011-0089-2 doi (NATIONALLICENCE)springer-10.1007/s00026-011-0089-2 Baxter R. Mathematical Sciences Institute, Australian National University, ACT 0200, Canberra, Australia aut Hard Squares for z [Elektronische Daten] -1 [R. Baxter] The hard square model in statistical mechanics has been investigated for the case when the activity z is −1. For cyclic boundary conditions, the characteristic polynomial of the transfer matrix has an intriguingly simple structure, all the eigenvalues x being zero, roots of unity, or solutions of x 3 = 4cos2(πm/N). Here we tabulate the results for lattices of up to 12 columns with cyclic or free boundary conditions and the two obvious orientations. We remark that they are all unexpectedly simple and that for the rotated lattice with free or fixed boundary conditions there are obvious likely generalizations to any lattice size. Springer Basel AG, 2011 statistical mechanics nationallicence lattice models nationallicence transfer matrices nationallicence Annals of Combinatorics SP Birkhäuser Verlag Basel 15/2(2011-06-01), 185-195 0218-0006 15:2<185 2011 15 26 https://doi.org/10.1007/s00026-011-0089-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00026-011-0089-2 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Baxter R. Mathematical Sciences Institute, Australian National University, ACT 0200, Canberra, Australia aut NATIONALLICENCE 773 0- Annals of Combinatorics SP Birkhäuser Verlag Basel 15/2(2011-06-01), 185-195 0218-0006 15:2<185 2011 15 26 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer