Multicritical crossovers near the dilute Bose gas quantum critical point

Many zero temperature transitions, involving the deviation in the value of a U(1) conserved charge from a quantized value, are described by the dilute Bose gas quantum critical paint. On such transitions, we study the consequences of perturbations which break the symmetry down to Z(N) in d spatial dimensions. For the case d = 1, N = 2, we obtain exact, finite temperature, multicritical crossover functions by a mapping to an integrable lattice model.