Symmetric connectedness in $T_0$-quasi-metric spaces

Abstract

We continue the study of asymmetry in $T_0$-quasi-metric spaces. In this context we introduce the property of symmetric connectedness for a $T_0$-quasi-metric space. We present some methods in order to find the symmetrically connected pairs of a $T_0$-quasi-metric space. We also show that the problem to determine the symmetry components of points turns out to be easier when formulated for the induced $T_0$-quasi-metric of an asymmetrically normed real vector space. In addition, as a kind of opposite to the notion of a metric space, we define antisymmetric $T_0$-quasi-metric spaces. Subsequently some useful results about antisymmetry can be emphasized by describing the property of antisymmetric connectedness for a $T_0$-quasi-metric space. Finally, we observe that there are natural relations between the theory of (anti)symmetrically connected $T_0$-quasi-metric spaces and the theory of connectedness in the sense of graph theory.