closed topology
11Extension topology — In topology, a branch of mathematics, an extension topology is a topology placed on the disjoint union of a topological space and another set. There are various types of extension topology, described in the sections below. Contents 1 Extension… …
12Subspace topology — In topology and related areas of mathematics, a subspace of a topological space X is a subset S of X which is equipped with a natural topology induced from that of X called the subspace topology (or the relative topology, or the induced topology …
13Alexandrov topology — In topology, an Alexandrov space (or Alexandrov discrete space) is a topological space in which the intersection of any family of open sets is open. It is an axiom of topology that the intersection of any finite family of open sets is open. In an …
14Counterexamples in Topology —   Author(s) Lynn Arthur Steen J. Ar …
15Particular point topology — In mathematics, the particular point topology (or included point topology) is a topology where sets are considered open if they are empty or contain a particular, arbitrarily chosen, point of the topological space. Formally, let X be any set and… …
16Initial topology — In general topology and related areas of mathematics, the initial topology (projective topology or weak topology) on a set X, with respect to a family of functions on X, is the coarsest topology on X which makes those functions continuous.The… …
17Weak topology — This article discusses the weak topology on a normed vector space. For the weak topology induced by a family of maps see initial topology. For the weak topology generated by a cover of a space see coherent topology. In mathematics, weak topology… …
18Long line (topology) — In topology, the long line (or Alexandroff line) is a topological space analogous to the real line, but much longer. Because it behaves locally just like the real line, but has different large scale properties, it serves as one of the basic… …
19Boundary (topology) — For a different notion of boundary related to manifolds, see that article. In topology, the boundary of a subset S of a topological space X is the set of points which can be approached both from S and from the outside of S . More formally, it is… …
20Coherent topology — In topology, a coherent topology is one that is uniquely determined by a family of subspaces. Loosely speaking, a topological space is coherent with a family of subspaces if it is a topological union of those subspaces. Contents 1 Definition 2… …
