LU TP 00-26, hep-ph/0006006
Do Instantons of the CP(N-1) Model Melt?
D. Diakonov, M. Maul
In the two-dimensional $CP^{N-1}$ model one can parametrize exact
many-instanton solutions via $N$ `constituents' (called `zindons').
This parameterization allows, in principle, a complete `melting'
of individual instantons. The model is therefore well suited
to study whether dynamics prefers a dilute or a strongly
overlapping ensemble of instantons. We study the statistical mechanics
of instantons both analytically and numerically. We find that at $N=2$
the instanton system collapses into zero-size instantons. At $N=3,4$
we find that well-isolated instantons are dynamically preferred
though 15-25\% of instantons have a considerable overlap with others.