## Abstract We show that, for each orientable surface Σ, there is a constant __c__~Σ~ so that, if __G__~1~ and __G__~2~ are embedded simultaneously in Σ, with representativities __r__~1~ and __r__~2~, respectively, then the minimum number cr(__G__~1~, __G__~2~) of crossings between the two maps sat
Regular Maps on Surfaces with Large Planar Width
✍ Scribed by Roman Nedela; Martin Škoviera
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 324 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0195-6698
No coin nor oath required. For personal study only.
✦ Synopsis
A map is a cell decomposition of a closed surface; it is regular if its automorphism group acts transitively on the flags, mutually incident vertex-edge-face triples. The main purpose of this paper is to establish, by elementary methods, the following result: for each positive integer w and for each pair of integers p ≥ 3 and q ≥ 3 satisfying 1/ p + 1/q ≤ 1/2, there is an orientable regular map with face-size p and valency q such that every non-contractible simple closed curve on the surface meets the 1-skeleton of the map in at least w points. This result has several interesting consequences concerning maps on surfaces, graphs and related concepts. For example, MacBeath's theorem about the existence of infinitely many Hurwitz groups, or Vince's theorem about regular maps of given type ( p, q), or residual finiteness of triangle groups, all follow from our result.
📜 SIMILAR VOLUMES
## Abstract Let __B(G)__ be the edge set of a bipartite subgraph of a graph __G__ with the maximum number of edges. Let __b~k~__ = inf{|__B(G)__|/|__E(G)__‖__G__ is a cubic graph with girth at least __k__}. We will prove that lim~k → ∞~ __b~k~__ ≥ 6/7.
Let k ≥ 2, be an integer and M be a closed two-manifold with Euler characteristic χ(M) ≤ 0. We prove that each polyhedral map G on M, which has at least (8k 2 + 6k -6)|χ (M)| vertices, contains a connected subgraph H of order k such that every vertex of this subgraph has, in G, the degree at most 4k
## Crown[n]cavitands were synthesized by alkylation of The presence of a sodium base enhances the formation of the 1,2-crown[n]cavitand and improves the yield. The tetrahydroxycavitands with polyethyleneglycol ditosylates. The bridging of two hydroxy groups at adjacent aromatic combination of 1,2-
In this paper we show that every variational solution of the steady-state Boussinesq equations (u, p, ) with thermocapillarity e!ect on the surface of the liquid has the following regularity: u3H( ), p3H( ), 3H( ) under appropriate hypotheses on the angles of the &2-D' container (a cross-section of