Absolute retracts as factors of normed linear spaces
Affine group acting on hyperspaces of compact convex subsets of ℝⁿ
For every n ≥ 2, let cc(ℝⁿ) denote the hyperspace of all nonempty compact convex subsets of the Euclidean space ℝⁿ endowed with the Hausdorff metric topology. Let cb(ℝⁿ) be the subset of cc(ℝⁿ) consisting of all compact convex bodies. In this paper we discover several fundamental properties of the natural action of the affine group Aff(n) on cb(ℝⁿ). We prove that the space E(n) of all n-dimensional ellipsoids is an Aff(n)-equivariant retract of cb(ℝⁿ). This is applied to show that cb(ℝⁿ) is homeomorphic...
An Equivariant Extension Theorem and G-Retracts with a Finite Structure.
An example of 2-dimensional quasihomeomorphic sets
An R-stable ANR which is not FR-stable
Another note on closed -cells in
ANR's and NES's in the category of mappings on metric spaces
Approximative retracts and fundamental retracts
Arc property of Kelley and absolute retracts for hereditarily unicoherent continua
We investigate absolute retracts for hereditarily unicoherent continua, and also the continua that have the arc property of Kelley (i.e., the continua that satisfy both the property of Kelley and the arc approximation property). Among other results we prove that each absolute retract for hereditarily unicoherent continua (for tree-like continua, for λ-dendroids, for dendroids) has the arc property of Kelley.
Are EC-spaces AE(metrizable)?