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Spanning retracts of a partially ordered set

โœ Scribed by D. Duffus; I. Rival; M. Simonovits

Publisher
Elsevier Science
Year
1980
Tongue
English
Weight
639 KB
Volume
32
Category
Article
ISSN
0012-365X

No coin nor oath required. For personal study only.

โœฆ Synopsis

Two general kinds of subsets of a partially ordered set P are always retracts of P:: (1) every maximal chain of P is a retract; (2) in P, every isometric, spanning subset of length one with no crowns is a retract. It follows that in a partially ordered set P with the fixed point property, every maximal chain of P is complete and every isometric, spanning fence of P is finite.

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