20.500.12556/DKUM-51873 Retracts of products of chordal graphs We characterize the graphs ▫$G$▫ that are retracts of Cartesian products of chordal graphs. We show that they are exactly the weakly modular graphs that do not contain ▫$K_{2;3}$▫, ▫$k$▫-wheels ▫$W_k$▫, and ▫$k$▫-wheels minus one spoke T$W_k^- ; (k ge 4)$T as induced subgraphs. We also show that these graphs ▫$G$▫ are exactly the cage-amalgamation graphs introduced by Brešar and Tepeh Horvat (2009); this solves the open question raised by these authors. Finally, we prove that replacing all products of cliques of $G$ by products of "solid" simplices, we obtain a polyhedral cell complex which, endowed with an intrinsic Euclidean metric, is a CAT(0) space. This generalizes similar results about median graphs as retracts of hypercubes (products of edges) and median graphs as 1-skeletons of CAT(0) cubical complexes. teorija grafov graf retrakt zastražena amalgamacija tetiven graf kartezični produkt grafov medianski graf graph theory graph retract gated amalgamation chordal graph Cartesian product of graphs median graph true false false Angleški jezik Neznan jezik Delo ni kategorizirano 2015-07-10 15:18:18 2015-07-10 15:18:18 2022-05-31 03:08:23 2019-07-11 07:30:43 2010 0 0 str. 1-20 št. 1134 Vol. 48 2010 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 2232-2094 519.17 15706713 15751513 URN:SI:UM:DK:NGAKPCB0 http://www.imfm.si/preprinti/PDF/01134.pdf 1 https://dk.um.si/Dokument.php?lang=slv&id=76433 Fakulteta za naravoslovje in matematiko 0 0 0