THE FLUCTUATING SURFACE HAMILTONIAN FOR THE CLASSICAL KAGOME ANTIFERROMAGNET

Integrating over spin wave degrees of freedom, we derive the effective Hamiltonian to describe the problem of the classical Kagome antiferromagnet in relevant variables. The intrinsically anharmonic character of this Hamiltonian, and the coupling between the continuous and discrete degrees of freedom contained within it, puts it into a completely new class of problem: that of highly fluctuating surfaces, for which the Hamiltonian gives a rigorous description of the thermodynamic properties at low T.