Equivariant cohomology and lower bounds for chromatic numbers. (English) Zbl 0756.05055
Trans. Am. Math. Soc. 333, No. 2, 567-577 (1992); correction ibid. 352, No. 4, 1951-1952 (2000).
Summary: We introduce a general topological method for obtaining a lower bound of the chromatic number of an \(n\)-graph. We present numerical lower bounds for intersection \(n\)-graphs.
MSC:
| 05C15 | Coloring of graphs and hypergraphs |
| 05C65 | Hypergraphs |
| 55U99 | Applied homological algebra and category theory in algebraic topology |
| 55N91 | Equivariant homology and cohomology in algebraic topology |
| 55T99 | Spectral sequences in algebraic topology |
