Closing in on Hill's conjecture Article uri icon

abstract

  • Borrowing L\%27aszl\%27o Sz\%27ekely%27s lively expression, we show that Hill%27s conjecture is ``asymptotically at least 98.5\%25 true. This long-standing conjecture states that the crossing number cr(Kn) of the complete graph Kn is (formula presented) for all n \geq 3. This has been verified only for n \leq 12. Using the flag algebra framework, Norin and Zwols obtained the best known asymptotic lower bound for the crossing number of complete bipartite graphs, from which it follows that for every sufficiently large n, cr(Kn) > 0.905 H(n). Also using this framework, we prove that asymptotically cr(Kn) is at least 0.985 H(n). We also show that the spherical geodesic crossing number of Kn is asymptotically at least 0.996 H(n). © 2019 Society for Industrial and Applied Mathematics
  • Borrowing L\'aszl\'o Sz\'ekely's lively expression, we show that Hill's conjecture is ``asymptotically at least 98.5\%25 true. This long-standing conjecture states that the crossing number cr(Kn) of the complete graph Kn is (formula presented) for all n \geq 3. This has been verified only for n \leq 12. Using the flag algebra framework, Norin and Zwols obtained the best known asymptotic lower bound for the crossing number of complete bipartite graphs, from which it follows that for every sufficiently large n, cr(Kn) > 0.905 H(n). Also using this framework, we prove that asymptotically cr(Kn) is at least 0.985 H(n). We also show that the spherical geodesic crossing number of Kn is asymptotically at least 0.996 H(n). © 2019 Society for Industrial and Applied Mathematics

publication date

  • 2019-01-01