EntityQ250509· pop 6· linked from 11 articlesTychonoff plankSign in to savetopological space that is used in mathematics as a counterexample to several plausible-sounding conjecturesConnectionsnormal spaceEntityordinal numberEntityproduct topologyEntityInternational Standard Book NumberEntitytopologyEntitytopological spaceEntityconjectureEntityMathWorldEntitycompact spaceEntitySpringer Science+Business MediaEntitycounterexampleEntityEric W. WeissteinEntityMathematical ReviewsEntityAddison-WesleyEntityStone–Čech compactificationEntityDover PublicationsEntityJohn L. KelleyEntityorder topologyEntityLynn SteenEntityfirst uncountable ordinalEntityCategoriesTopological spaces