Date | Chapter | Description |
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Sep 1 | | Simplicial complexes: CW-structure, examples |
Sep 3 | | Simplicial complex examples, Stanley-Reisner rings |
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Sep 6 | | Labor Day! (no class) |
Sep 8 | | The Nerve Lemma and Helly Theorem |
Sep 10 | | Alexander Duality; proof of Topological Helly Theorem |
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Sep 13 | | Poset topology and Möbius inversion |
Sep 15 | | Hall's Theorem: Möbius = reduced Euler |
Sep 17 | | Lattices; Hall's application of Möbius inversion |
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Sep 20 | | Poset duality, complements |
Sep 22 | | Crapo and Homotopy Complementation Theorems |
Sep 24 | | Homotopy Complementation proof |
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Sep 27 | | Homotopy Complementation applications |
Sep 29 | | Partition lattices, distributive and modular lattices |
Oct 1 | | Modular and left-modular elements |
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Oct 4 | | Homotopy of lattices with modular chains via complementation |
Oct 6 | | EL-labelings |
Oct 8 | | Left-modular elements and labelings |
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Oct 11 | | Supersolvable lattices |
Oct 13 | | Semimodular lattices |
Oct 15 | | Fall Break! (no class) |
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Oct 18 | | Semimodular lattice examples, geometric lattices |
Oct 20 | | Matroids <-> geometric lattices |
Oct 22 | | EL-labelings of semimodular lattices |
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Oct 25 | | Shellings, rearrangement lemmas |
Oct 27 | | Collapsing, homotopy type of shellable complexes |
Oct 29 | | EL-labelings give shellings |
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Nov 1 | | Cohen-Macaulay complexes and local homology |
Nov 3 | | The dunce cap; various definitions of skeleton |
Nov 5 | | sequentially Cohen-Macaulay complexes |
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Nov 8 | | connectivity parameter: depth |
Nov 10 | | depth is a topological invariant; Krull dimension |
Nov 12 | | (ring theoretic) depth |
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Nov 15 | | Local cohomology of a ring: Koszul and modified Cech complexes |
Nov 17 | | Cohomology <-> Local cohomology of Stanley-Reisner |
Nov 19 | | Hilbert series and h-vectors |
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Nov 22 | | h-vectors, M-vectors, and the Upper Bound Theorem |
Nov 24 | | Thanksgiving! (no class) |
Nov 26 | | Thanksgiving! (no class) |
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Nov 29 | | h-vectors of shellable and partitionable complexes |
Dec 1 | | CL-labelings; vertex-decomposability |
Dec 3 | | Discrete Morse theory: connection with continuous Morse theory |
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Dec 6 | | Discrete Morse theory: Morse functions give collapsing |
Dec 8 | | Discrete Morse theory: examples, Morse matchings |
Dec 10 | | Discrete Morse theory: shellings, brief idea of poset Morse theory |