orientable
81Holonomy — Parallel transport on a sphere depends on the path. Transporting from A → N → B → A yields a vector different from the initial vector. This failure to return to the initial vector is measured by the holonomy of the connection. In differential… …
82Edge coloring — A 3 edge coloring of the Desargues graph. In graph theory, an edge coloring of a graph is an assignment of “colors” to the edges of the graph so that no two adjacent edges have the same color. For example, the figure to the right shows an edge… …
83Seifert surface — In mathematics, a Seifert surface is a surface whose boundary is a given knot or link. Such surfaces can be used to study the properties of the associated knot or link. For example, many knot invariants are most easily calculated using a Seifert… …
84Rotation system — In combinatorial mathematics, rotation systems encode embeddings of graphs onto orientable surfaces, by describing the circular ordering of a graph s edges around each vertex.A more formal definition of a rotation system involves pairs of… …
85Aspherical space — In topology, an aspherical space is a topological space with all higher homotopy groups equal to {0}. If one works with CW complexes, one can reformulate this condition: an aspherical CW complex is a CW complex whose universal cover is… …
86Comparison of movie cameras — See list of movie cameras for a comprehensive listing of movie cameras. The following tables make a comparison of movie cameras that are in common professional usage in recent years. This list is strictly limited to film based cameras, in order… …
87Cohomological dimension — In abstract algebra, cohomological dimension is an invariant which measures the homological complexity of representations of a group. It has important applications in geometric group theory, topology, and algebraic number theory. Contents 1… …
88Causal structure — This article is about the possible causal relationships among points in a Lorentzian manifold. For classification of Lorentzian manifolds according to the types of causal structures they admit, see Causality conditions. In mathematical physics,… …
89Cobordisme — En topologie différentielle, le cobordisme est une relation réflexive, transitive et symétrique entre variétés différentielles compactes. Deux variétés compactes M et N sont dites cobordantes ou en cobordisme si leur réunion disjointe peut être… …
90Difféomorphisme — En mathématiques, un difféomorphisme est un isomorphisme dans la catégorie des variétés différentielles : c est une bijection différentiable d une variété dans une autre, dont la bijection réciproque est aussi différentiable. Image d une… …
