On statistical mechanics of instantons in the CP(Nc-1)model

We introduce an explicit form of the multi-instanton weight including also instanton-anti-instanton interactions for arbitrary N-c in the two-dimensio nal CPNc-1 model. To that end, we use the parametrization of multi-instanto ns in terms of instanton 'constituents' which we call 'zindons for short, W e study the statistical mechanics of zindons analytically (by means of the Debye-Hukel approximation) and numerically (running a Metropolis algorithm) . Though the zindon parametrization allows for a complete 'melting' of inst antons we find that, through a combination of dynamical and purely geometri c factors, a dominant portion of topological charge is residing in well-sep arated instantons and anti-instantons. (C) 2000 Elsevier Science B.V. All r ights reserved.