Incidence combinatorics of resolutions
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Eva-Maria Feichtner [1] ; Dmitry N. Kozlov [2]
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[1] Swiss Federal Institute of Technology in Zurich
Swiss Federal Institute of Technology in Zurich
Zürich, Suiza
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[2] Department of Mathematics, KTH Stockholm, Suecia
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- Localización: Selecta Mathematica, New Series, ISSN 1022-1824, Vol. 10, Nº. 1, 2004, págs. 37-60
- Idioma: inglés
- DOI: 10.1007/s00029-004-0298-1
- Enlaces
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Resumen
We introduce notions of combinatorial blowups, building sets, and nested sets for arbitrary meet-semilattices. This gives a~common abstract framework for the incidence combinatorics occurring in the context of De Concini-Procesi models of subspace arrangements and resolutions of singularities in toric varieties. Our main theorem states that a sequence of combinatorial blowups, prescribed by a building set in linear extension compatible order, gives the face poset of the corresponding simplicial complex of nested sets. As applications we trace the incidence combinatorics through every step of the De Concini-Procesi model construction, and we introduce the notions of building sets and nested sets to the context of toric varieties.
There are several other instances, such as models of stratified manifolds and certain graded algebras associated with finite lattices, where our combinatorial framework has been put to work; we present an outline at the end of this paper.
