Computational topology | Simplicial homology

Simplicial homology

In algebraic topology, simplicial homology is the sequence of homology groups of a simplicial complex. It formalizes the idea of the number of holes of a given dimension in the complex. This generalizes the number of connected components (the case of dimension 0). Simplicial homology arose as a way to study topological spaces whose building blocks are n-simplices, the n-dimensional analogs of triangles. This includes a point (0-simplex), a line segment (1-simplex), a triangle (2-simplex) and a tetrahedron (3-simplex). By definition, such a space is homeomorphic to a simplicial complex (more precisely, the geometric realization of an abstract simplicial complex). Such a homeomorphism is referred to as a triangulation of the given space. Many topological spaces of interest can be triangulated, including every smooth manifold (Cairns and Whitehead). Simplicial homology is defined by a simple recipe for any abstract simplicial complex. It is a remarkable fact that simplicial homology only depends on the associated topological space. As a result, it gives a computable way to distinguish one space from another. (Wikipedia).

Simplicial homology
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Related pages

MATLAB | Betti number | Algebraic topology | Abstract simplicial complex | Persistent homology | Simplicial homotopy | Trivial group | Cellular homology | Chain complex | Homological connectivity | Quotient group | Tetrahedron | Homomorphism | Topological data analysis | Singular homology | Connected space | Free abelian group | Chain (algebraic topology) | Orientability | Triangulation (topology) | Functor | Manifold | Rank of an abelian group | Simplicial complex | Data mining