76 research outputs found

    Meunier Conjecture

    Full text link
    Fr\'ed\'eric Meunier's question about a multicolored Sperner lemma is addressed, leaving the question of connectivity for the color hypergraphs of such a multicolored simplex. Sperner's lemma asserts the existence of a simplex using all the colors for any vertex coloring of a subdivision of a large simplex with appropriate boundary conditions. Meunier's questions generalizes this to the situation of having several such colorings and asserts the existence of a simplex using enough different colors from each coloring

    Fundamental Groups of Random Clique Complexes

    Full text link
    Clique complexes of Erd\H{o}s-R\'{e}nyi random graphs with edge probability between nβˆ’13n^{-{1\over 3}} and nβˆ’12n^{-{1\over 2}} are shown to be aas not simply connected. This entails showing that a connected two dimensional simplicial complex for which every subcomplex has fewer than three times as many edges as vertices must have the homotopy type of a wedge of circles, two spheres and real projective planes. Note that nβˆ’13n^{-{1\over 3}} is a threshold for simple connectivity and nβˆ’12n^{-{1\over 2}} is one for vanishing first \F_2 homology.Comment: 7 pages statement of Theorem 1.2 correcte

    Random Walks and Mixed Volumes of Hypersimplices

    Full text link
    Below is a method for relating a mixed volume computation for polytopes sharing many facet directions to a symmetric random walk. The example of permutahedra and particularly hypersimplices is expanded upon.Comment: 6 page
    • …
    corecore