Presentation and central extensions of mapping class groups
نویسندگان
چکیده
منابع مشابه
Class Groups of Dihedral Extensions
Let L/F be a dihedral extension of degree 2p, where p is an odd prime. Let K/F and k/F be subextensions of L/F with degrees p and 2, respectively. Then we will study relations between the p-ranks of the class groups Cl(K) and Cl(k). 1. A Short History of Reflection Theorems Results comparing the p-rank of class groups of different number fields (often based on the interplay between Kummer theor...
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Let $G$ be a finite non-abelian $p$-group and $L(G)$ denotes the absolute center of $G$. Also, let $Aut^{L}(G)$ and $Aut_c(G)$ denote the group of all absolute central and the class preserving automorphisms of $G$, respectively. In this paper, we give a necessary and sufficient condition for $G$ such that $Aut_c(G)=Aut^{L}(G)$. We also characterize all finite non-abelian $p$-groups of order $p^...
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2 Topology of surfaces 5 2.1 The dimension 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2 Classi cation of surfaces . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 Circles and arcs on surfaces . . . . . . . . . . . . . . . . . . . . . 7 2.4 Pants decompositions . . . . . . . . . . . . . . . . . . . . . . . . 9 2.5 Geometric structures on surfaces . . . . . . . . . . . . . . ....
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1996
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-96-01509-7