منابع مشابه
On Generators of Crystallographic Groups and Actions on Flat Orbifolds
We find new bounds on the minimal number of generators of crystallographic groups with p-group holonomy. We also show that similar bounds exist on the minimal number of generators of the abelianizations of arbitrary crystallographic groups. As a consequence, we show that this restricts the rank of elementary abelian p-groups that can act effectively on closed connected flat orbifolds.
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We prove that any asymptotically locally Euclidean scalar-flat Kähler 4-orbifold whose isometry group contains a 2-torus is isometric, up to an orbifold covering, to a quaternionic-complex quotient of a k-dimensional quaternionic vector space by a (k − 1)-torus. In order to do so, we first prove that any compact anti-self-dual 4-orbifold with positive Euler characteristic whose isometry group c...
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ژورنال
عنوان ژورنال: Pacific Journal of Mathematics
سال: 1996
ISSN: 0030-8730,0030-8730
DOI: 10.2140/pjm.1996.172.299