Tie-points and fixed-points in N^*

Alan Dow; Saharon Shelah

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arXiv · 0711.3037

Tie-points and fixed-points in N^*

Alan Dow·Saharon Shelah

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Abstract

A point x is a (bow) tie-point of a space X if X setminus {x} can be partitioned into (relatively) clopen sets each with x in its closure. Tie-points have appeared in the construction of non-trivial autohomeomorphisms of betaN setminus N and in the recent study of (precisely) 2-to-1 maps on betaN setminus N . In these cases the tie-points have been the unique fixed point of an involution on betaN setminus N. This paper is motivated by the search for 2-to-1 maps and obtaining tie-points of strikingly differing characteristics.

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BibTeX RIS

Alan Dow, Saharon Shelah. 2007-11-19. Tie-points and fixed-points in N^*. https://arxiv.org/abs/0711.3037

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