2018/09/17 by Jingyin Huang, Huang, Jingyin, Michael Pawliuk +5 · 1 citation
Mathematics · #Combinatorics (math.CO) #FOS: Mathematics #Logic (math.LO) #math.CO #math.LO
paper · pdf · doi:10.48550/arxiv.1809.06435
arxiv created 2018/09/17 · arxiv updated 2018/09/19
We study the problem of extending partial isomorphisms for hypertournaments, which are relational structures generalizing tournaments. This is a generalized version of an old question of Herwig and Lascar. We show that the generalized problem has a negative answer, and we provide a positive answer in a special case. As a corollary, we show that the extension property holds for tournaments in case the partial isomorphisms have pairwise disjoint ranges and pairwise disjoint domains.