2012/10/02 by Bilet, Viktoriia, Dovgoshey, Oleksiy
#28A10 #54E35 #Classical Analysis and ODEs (math.CA) #FOS: Mathematics #Metric Geometry (math.MG)
paper · doi:10.48550/arxiv.1210.0656
Let (X,d,p) be a metric space with a metric d and a marked point p. We define the set of w-strongly porous at 0 subsets of [0,∞) and prove that the distance set d(x,p): x∈ X is w-strongly porous at 0 if and only if every pretangent space to X at p is bounded.