Ziegler’s Multireflection Arrangements Are Free
نویسندگان
چکیده
منابع مشابه
NOT ALL FREE ARRANGEMENTS ARE K ( n , 1 ) PAUL
We produce a one-parameter family of hyperplane arrangements that are counterexamples to the conjecture of Saito that the complexified complement of a free arrangement is K(n, 1 ). These arrangements are the restriction of a one-parameter family of arrangements that arose in the study of tilings of certain centrally symmetric octagons. This other family is discussed as well. I. Definitions and ...
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The number of preferential trading arrangements (PTAs) approved under the General Agreement on Tariffs and Trade (GATT) and the World Trade Organization (WTO) has increased significantly, from just one in 1949 to more than 100 today. In fact, PTAs such as the European Union and North American Free Trade Agreement (NAFTA) have more power than the United Nations. In a 1995 study, the WTO Secretar...
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Let V be a finite dimensional complex vector space and W ⊆ GL(V ) be a finite complex reflection group. Let V reg be the complement in V of the reflecting hyperplanes. We prove that V reg is a K(π, 1) space. This was predicted by a classical conjecture, originally stated by Brieskorn for complexified real reflection group. The complexified real case follows from a theorem of Deligne and, after ...
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ژورنال
عنوان ژورنال: Experimental Mathematics
سال: 2014
ISSN: 1058-6458,1944-950X
DOI: 10.1080/10586458.2014.939787