# Antichains in the homomorphism order of graphs

Dwight Duffus; Peter, L. Erdös; Jaroslav Nešetřil; Lajos Soukup

Commentationes Mathematicae Universitatis Carolinae (2007)

- Volume: 48, Issue: 4, page 571-583
- ISSN: 0010-2628

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topDuffus, Dwight, et al. "Antichains in the homomorphism order of graphs." Commentationes Mathematicae Universitatis Carolinae 48.4 (2007): 571-583. <http://eudml.org/doc/250192>.

@article{Duffus2007,

abstract = {Let $\mathbb \{G\}$ and $\mathbb \{D\}$, respectively, denote the partially ordered sets of homomorphism classes of finite undirected and directed graphs, respectively, both ordered by the homomorphism relation. Order theoretic properties of both have been studied extensively, and have interesting connections to familiar graph properties and parameters. In particular, the notion of a duality is closely related to the idea of splitting a maximal antichain. We construct both splitting and non-splitting infinite maximal antichains in $\mathbb \{G\}$ and in $\mathbb \{D\}$. The splitting maximal antichains give infinite versions of dualities for graphs and for directed graphs.},

author = {Duffus, Dwight, Erdös, Peter, L., Nešetřil, Jaroslav, Soukup, Lajos},

journal = {Commentationes Mathematicae Universitatis Carolinae},

keywords = {partially ordered set; homomorphism order; duality; antichain; splitting property; partially ordered set; homomorphism order; duality; antichain; splitting property},

language = {eng},

number = {4},

pages = {571-583},

publisher = {Charles University in Prague, Faculty of Mathematics and Physics},

title = {Antichains in the homomorphism order of graphs},

url = {http://eudml.org/doc/250192},

volume = {48},

year = {2007},

}

TY - JOUR

AU - Duffus, Dwight

AU - Erdös, Peter, L.

AU - Nešetřil, Jaroslav

AU - Soukup, Lajos

TI - Antichains in the homomorphism order of graphs

JO - Commentationes Mathematicae Universitatis Carolinae

PY - 2007

PB - Charles University in Prague, Faculty of Mathematics and Physics

VL - 48

IS - 4

SP - 571

EP - 583

AB - Let $\mathbb {G}$ and $\mathbb {D}$, respectively, denote the partially ordered sets of homomorphism classes of finite undirected and directed graphs, respectively, both ordered by the homomorphism relation. Order theoretic properties of both have been studied extensively, and have interesting connections to familiar graph properties and parameters. In particular, the notion of a duality is closely related to the idea of splitting a maximal antichain. We construct both splitting and non-splitting infinite maximal antichains in $\mathbb {G}$ and in $\mathbb {D}$. The splitting maximal antichains give infinite versions of dualities for graphs and for directed graphs.

LA - eng

KW - partially ordered set; homomorphism order; duality; antichain; splitting property; partially ordered set; homomorphism order; duality; antichain; splitting property

UR - http://eudml.org/doc/250192

ER -

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