Kwai Man Fan proved that if the intersection lattice of a line arrangement does not contain a cycle, then the fundamental group of its complement is a direct sum of infinite and cyclic free groups. He also conjectured that the converse is true as well. The main purpose of this paper is to prove this conjecture.
Eliyahu, Meital  1 ; Liberman, Eran  1 ; Schaps, Malka  1 ; Teicher, Mina  1
@article{10_2140_agt_2010_10_1285,
author = {Eliyahu, Meital and Liberman, Eran and Schaps, Malka and Teicher, Mina},
title = {The characterization of a line arrangement whose fundamental group of the complement is a direct sum of free groups},
journal = {Algebraic and Geometric Topology},
pages = {1285--1304},
year = {2010},
volume = {10},
number = {3},
doi = {10.2140/agt.2010.10.1285},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2010.10.1285/}
}
TY - JOUR AU - Eliyahu, Meital AU - Liberman, Eran AU - Schaps, Malka AU - Teicher, Mina TI - The characterization of a line arrangement whose fundamental group of the complement is a direct sum of free groups JO - Algebraic and Geometric Topology PY - 2010 SP - 1285 EP - 1304 VL - 10 IS - 3 UR - http://geodesic.mathdoc.fr/articles/10.2140/agt.2010.10.1285/ DO - 10.2140/agt.2010.10.1285 ID - 10_2140_agt_2010_10_1285 ER -
%0 Journal Article %A Eliyahu, Meital %A Liberman, Eran %A Schaps, Malka %A Teicher, Mina %T The characterization of a line arrangement whose fundamental group of the complement is a direct sum of free groups %J Algebraic and Geometric Topology %D 2010 %P 1285-1304 %V 10 %N 3 %U http://geodesic.mathdoc.fr/articles/10.2140/agt.2010.10.1285/ %R 10.2140/agt.2010.10.1285 %F 10_2140_agt_2010_10_1285
Eliyahu, Meital; Liberman, Eran; Schaps, Malka; Teicher, Mina. The characterization of a line arrangement whose fundamental group of the complement is a direct sum of free groups. Algebraic and Geometric Topology, Tome 10 (2010) no. 3, pp. 1285-1304. doi: 10.2140/agt.2010.10.1285
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