Anzeige
Erschienen in:
2007 | OriginalPaper | Buchkapitel
General Walks and Their Characteristics
Erschienen in: Walks on Ordinals and Their Characteristics
Verlag: Birkhäuser Basel
Aktivieren Sie unsere intelligente Suche, um passende Fachinhalte oder Patente zu finden.
Wählen Sie Textabschnitte aus um mit Künstlicher Intelligenz passenden Patente zu finden. powered by
Markieren Sie Textabschnitte, um KI-gestützt weitere passende Inhalte zu finden. powered by
One of the most basic questions frequently asked about set-theoretical trees is the question whether they contain any
cofinal branch
, a branch that intersects each level of the tree. The fundamental importance of this question has already been realized in the work of Kurepa [65] and then later in the works of Erdős and Tarski [32] in their respective attempts to develop the theory of partition calculus and large cardinals. A tree
T
of height equal to some regular cardinal
θ
may not have a cofinal branch for a very special reason as the following definition indicates.