Which topologies can have immediate successors in the lattice of T1-topologies?


  • Ofelia T. Alas Universidade de Sao Paulo
  • Richard G. Wilson Universidad Autónoma Metropolitana




Lattice of T1-topologies, Maximal point, KC-space, Cover of a topology, Upper topology, Lower topology


We give a new characterization of those topologies which have an immediate successor or cover in the lattice of T1-topologies on a set and show that certain classes of compact and countably compact topologies do not have covers.


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Author Biographies

Ofelia T. Alas, Universidade de Sao Paulo

Instituto de Matemática e Estatística

Richard G. Wilson, Universidad Autónoma Metropolitana

Departamento de Matemáticas


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How to Cite

O. T. Alas and R. G. Wilson, “Which topologies can have immediate successors in the lattice of T1-topologies?”, Appl. Gen. Topol., vol. 5, no. 2, pp. 231–242, Oct. 2004.