# On the difference between real and complex arrangements

@article{Ziegler1992OnTD, title={On the difference between real and complex arrangements}, author={G{\"u}nter M. Ziegler}, journal={Mathematische Zeitschrift}, year={1992}, volume={212}, pages={1-11} }

If B is an arrangement of linear complex hyperplanes in C d , then the following can be constructed from knowledge of its intersection lattice: (a) the cohomology groups of the complement (Br), (b) the cohomology algebra of the complement (OS), (c) the fundamental group of the complement, if d ≤ 2, (d) the singularity link up to homeomorphism, if d ≤ 3, (e) the singularity link up to homotopy type (ZZ). If Bis, more generally, a 2-arrangement in IR 2d (an arrangement of real subspaces of… Expand

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