Monthly Archives: December 2013

From Euler Characteristics to Cohomology (II)

Boundary Maps Here’s a brief recap of the previous article: we learnt that in refining a cell decomposition of an object M, we can, at each step, pick an i-dimensional cell and divide it in two. In this way, we … Continue reading

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From Euler Characteristics to Cohomology (I)

[ Warning: this is primarily an expository article, so the proofs are not airtight, but they should be sufficiently convincing. ] The five platonic solids were well-known among the ancient Greeks (V, E, F denote the number of vertices, edges and faces respectively): … Continue reading

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