Monte Carlo Simulations of the two-dimensional dipolar fluid

We study a two-dimensional fluid of dipolar hard disks by Monte Carlo simulations in a square with periodic boundary conditions and on the surface of a sphere. The theory of the dielectric constant and the asymptotic behaviour of the equilibrium pair correlation function in the fluid phase is derived for both geometries. After having established the equivalence of the two methods we study the stability of the liquid phase in the canonical ensemble. We give evidence of a phase made of living polymers at low temperatures and provide a tentative phase diagram.