Homotopy types of line arrangements

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

We prove that the complement of a real affine line arrangement in C2 is homotopy equivalent to the canonical 2-complex associated with Randell's presentation of the fundamental group. This provides a much smaller model for the homotopy type of the complement of a real affine 2- or central 3-arrangement than the Salvetti complex and its cousins. As an application we prove that these exist (infinitely many) pairs of central arrangements in C3 with different underlying matroids whose complements are homotopy equivalent. We also show that two real 3-arrangements whose oriented matroids are connected by a sequence of flips are homotopy equivalent.

Original languageEnglish (US)
Pages (from-to)139-150
Number of pages12
JournalInventiones Mathematicae
Volume111
Issue number1
DOIs
StatePublished - Dec 1993

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Homotopy Type
Arrangement
Homotopy
Complement
Line
Oriented Matroid
Flip
Matroid
Fundamental Group
Model

ASJC Scopus subject areas

  • Mathematics(all)

Cite this

Homotopy types of line arrangements. / Falk, Michael J.

In: Inventiones Mathematicae, Vol. 111, No. 1, 12.1993, p. 139-150.

Research output: Contribution to journalArticle

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