Unexpected scenario of glass transition in polymer globules: An exactly enumerable model

We introduce a lattice model of glass transition in polymer globules. This model exhibits ergodicity breaking in which the disjoint regions of phase s pace do not arise uniformly, but as small chambers whose number increases e xponentially with polymer density. Chamber sizes obey power law distributio n, making phase space similar to a fractal foam. This clearly demonstrates the importance of the phase space geometry and topology in describing any g lass-forming system, such as semicompact polymers during protein folding.