On statistical mechanics of instantons in the CPNc-1model

We introduce an explicit form of the multi-instanton weight including also instanton-anti-instanton interactions for arbitrary N(c) in the two-dimensional CP(Nc-1) model. To that end, we use the parametrization of multi-instantons in terms of instanton 'constituents' which we call 'zindons for short, We 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 instantons we find that, through a combination of dynamical and purely geometric factors, a dominant portion of topological charge is residing in well-separated instantons and anti-instantons. (C) 2000 Elsevier Science B.V. All rights reserved.