Skip to main content Accessibility help
×
Home

Ultrafilters of character ω1

  • Klaas Pieter Hart (a1) (a2)

Abstract

Using side-by-side Sacks forcing, it is shown that it is consistent that 2ω be large and that there be many types of ultrafilters of character ω1.

Copyright

Corresponding author

Department of Mathematics and Computer Science, Technische Hogeschool te Delft, 2600 AJ Delft, The Netherlands

References

Hide All
[Ba]Baumgartner, J. E., Sacks forcing and the total failure of Martin's axiom, Topology and Its Applications, vol. 19 (1985), pp. 211225.
[BaLa]Baumgartner, J. E. and Laver, R., Iterated perfect-set forcing, Annals of Mathematical Logic, vol. 17(1979), pp. 271288.
[BlSh]Blass, A. and Shelah, S., Near coherence of filters. III: A simplified consistency proof (to appear).
[BuBu]Bukovský, L. and Butkovičová, E., Ultrafilter with ℵ0 predecessors in Rudin-Frolik order, Commentationes Mathematicae Universitatis Carolinae, vol. 22 (1981), pp. 429447.
[Bu1]Butkovičová, E., Gaps in Rudin-Frolík order, General topology and its relations to modern analysis and algebra, V (proceedings of the fifth Prague symposium), Heldermann, Berlin, 1983, pp. 5658.
[Bu2]Butkovičová, E., Short branches in Rudin-Frolik order, Commentationes Mathematicae Universitatis Carolinae, vol. 26 (1985), pp. 631635.
[CoVo]Copláková, E. and Vojtáš, P., A new sufficient condition for the existence of Q-points in βωω, Topology, theory and applications (Császár, Á., editor), Colloquia Mathematica Societatis János Bolyai, vol. 41, North-Holland, Amsterdam, 1985, pp. 199208.
[vD]van Douwen, E. K., The integers and topology, Handbook of set-theoretic topology, North-Holland, Amsterdam, 1984, pp. 111167.
[Ku1]Kunen, K., Weak P-points in N*, Topology, II (Császár, Á., editor), Colloquia Mathematica Societatis János Bolyai, vol. 23, North-Holland, Amsterdam, 1980, pp. 741749.
[Ku2]Kunen, K., Set theory, North-Holland, Amsterdam, 1980.
[Ku3]Kunen, K., letter to the author.
[La]Laver, R., Products of infinitely many perfect trees, Journal of the London Mathematical Society, ser. 2, vol. 29 (1984), pp. 385396.
[vM]van Mill, J., An introduction to βω, Handbook of set-theoretic topology, North-Holland, Amsterdam, 1984, pp. 503567.
[Ru]Rudin, M. E., Partial orders on the types of βN, Transactions of the American Mathematical Society, vol. 155 (1971), pp. 353362.
[Sh]Shelah, S., Proper forcing, Lecture Notes in Mathematics, vol. 940, Springer-Verlag, Berlin, 1982.
[S0]Solomon, R. C., A type in βN with ℵ0 relative types, Fundamenta Mathematicae, vol. 79 (1972), pp. 209212.

Keywords

Related content

Powered by UNSILO

Ultrafilters of character ω1

  • Klaas Pieter Hart (a1) (a2)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.