Freeness of conic-line arrangements in
Henry K. Schenck
University of Illinois, Urbana, United StatesŞtefan O. Tohǎneanu
University of Cincinnati, United States
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Abstract
Let be a collection of smooth rational plane curves. We prove that the addition–deletion operation used in the study of hyperplane arrangements has an extension which works for a large class of arrangements of smooth rational curves, giving an inductive tool for understanding the freeness of the module of logarithmic differential forms with pole along . We also show that the analog of Terao’s conjecture (freeness of is combinatorially determined if is a union of lines) is false in this setting.
Cite this article
Henry K. Schenck, Ştefan O. Tohǎneanu, Freeness of conic-line arrangements in . Comment. Math. Helv. 84 (2009), no. 2, pp. 235–258
DOI 10.4171/CMH/161