Totally disconnected space

In topology and related branches of mathematics, a totally disconnected space is a topological space that has only singletons as connected subsets.An important example of a totally disconnected space is the Cantor set, which is homeomorphic to the set of p-adic integers.Another example, playing a key role in algebraic number theory, is the field Qp of p-adic numbers.is totally disconnected if the connected components inEquivalently, for each pair of distinct points, there is a pair of disjoint open neighborhoodsEvery totally separated space is evidently totally disconnected but the converse is false even for metric spaces.to be the Cantor's teepee, which is the Knaster–Kuratowski fan with the apex removed.is totally disconnected but its quasicomponents are not singletons.For locally compact Hausdorff spaces the two notions (totally disconnected and totally separated) are equivalent.Confusingly, in the literature (for instance[3]) totally disconnected spaces are sometimes called hereditarily disconnected,[4] while the terminology totally disconnected is used for totally separated spaces.[4] The following are examples of totally disconnected spaces: Letdenotes the largest connected subset containingIn fact this space is not only some totally disconnected quotient but in a certain sense the biggest: The following universal property holds: For any totally disconnected space, there exists a unique continuous map
extremally disconnected spacetopologymathematicstopological spacesingletonsconnectedsubsetsCantor sethomeomorphicalgebraic number theoryp-adic numbersconnected componentstotally separated spacequasicomponentsintersectionclopenneighborhoodsmetric spacesCantor's teepeeKnaster–Kuratowski fanlocally compactHausdorff spacesDiscrete spacesrational numbersirrational numbersprofinite groupsCantor spaceBaire spaceSorgenfrey linesmall inductive dimensionErdős spaceExtremally disconnectedStone spacesSubspacesproductscoproductsT1 spacescompactmetric spacelocally compact Hausdorff spacecountableequivalence relationquotient topologyfinest topologyuniversal propertyTotally disconnected groupEngelking, RyszardMunkres, James R.Upper Saddle River, NJPrentice Hall, IncRudin, WalterMcGraw-Hill Science/Engineering/MathDover Publications