R-closedness and Upper semicontinuity
Abstract
Let be a pointwise almost periodic decomposition of a compact metrizable space . Then is -closed if and only if is usc. Moreover, if there is a finite index normal subgroup of an -closed flow on a compact manifold such that the orbit closures of consist of codimension compact connected elements and "few singularities" for or 2, then the orbit class space of is a compact -dimensional manifold with conners. In addition, let be a nontrivial -closed vector field on a connected compact 3-manifold . Then one of the following holds: 1) The orbit class space is or and each interior point of is two dimensional. 2) is open dense and . 3) There is a nontrivial non-toral minimal set. On the other hand, let be a flow on a compact metrizable space and a finite index normal subgroup. Then we show that is -closed if and only if so is .
Cite
@article{arxiv.1209.0166,
title = {R-closedness and Upper semicontinuity},
author = {Tomoo Yokoyama},
journal= {arXiv preprint arXiv:1209.0166},
year = {2012}
}