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arXiv · 0802.2865

Quantifying Homology Classes

Chao Chen·Daniel Freedman
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Abstract

We develop a method for measuring homology classes. This involves three problems. First, we define the size of a homology class, using ideas from relative homology. Second, we define an optimal basis of a homology group to be the basis whose elements' size have the minimal sum. We provide a greedy algorithm to compute the optimal basis and measure classes in it. The algorithm runs in $O(β^4 n^3 \log^2 n)$ time, where $n$ is the size of the simplicial complex and $β$ is the Betti number of the homology group. Third, we discuss different ways of localizing homology classes and prove some hardness results.

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Chao Chen, Daniel Freedman. 2008-02-20. Quantifying Homology Classes. https://arxiv.org/abs/0802.2865

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