Cycles and Matchings in Randomly Perturbed Digraphs and Hypergraphs

  title={Cycles and Matchings in Randomly Perturbed Digraphs and Hypergraphs},
  author={Michael Krivelevich and Matthew Kwan and Benny Sudakov},
  journal={Combinatorics, Probability and Computing},
  pages={909 - 927}
We give several results showing that different discrete structures typically gain certain spanning substructures (in particular, Hamilton cycles) after a modest random perturbation. First, we prove that adding linearly many random edges to a dense k-uniform hypergraph ensures the (asymptotically almost sure) existence of a perfect matching or a loose Hamilton cycle. The proof involves an interesting application of Szemerédi's Regularity Lemma, which might be independently useful. We next prove… 
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