We present a comprehensive study of the lattice restricted primitive model, i.e., a lattice gas consisting of an equal number of positively and negatively charged particles interacting via on-site exclusion and a 1/r potential. On the cubic lattice, Monte Carlo simulations show a line of Néel points separating a disordered, high-temperature phase from a phase with global antiferromagnetic order...

Using the standard Coxeter presentation for the symmetric group Sn, two reduced expressions for the same group element are said to be commutation equivalent if we can obtain one expression from the other by applying a finite sequence of commutations. The resulting equivalence classes of reduced expressions are called commutation classes. How many commutation classes are there for the longest el...

We construct families of piecewise linear representations cpl representations of the symmetric group Sn and the a ne Weyl group e Sn of type A n acting on the space of triangles Xn We nd a nontrivial family of local cpl invariants for the action of the symmetric group Sn on the space Xn and construct one global invariant w r t the action of the a ne Weyl group e Sn so called cocharge We nd the ...

New renormalization-group algorithms are developed with adaptive representations of the renormalized system which automatically express only signi cant interactions. As the amount of statistics grows, more interactions enter, thereby systematically reducing the truncation error. This allows statistically optimal calculation of thermodynamic limits, in the sense that it achieves accuracy " in ju...