Finite presentation of fibre products of metabelian groups

被引:8
作者
Baumslag, G
Bridson, MR
Holt, DF
Miller, CF
机构
[1] Math Inst, Oxford OX1 3LB, England
[2] CUNY City Coll, Dept Math, New York, NY 10031 USA
[3] Univ Warwick, Inst Math, Coventry CV4 7AL, W Midlands, England
[4] Univ Melbourne, Dept Math & Stat, Parkville, Vic 3052, Australia
关键词
SUBGROUPS;
D O I
10.1016/S0022-4049(02)00307-9
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We show that if Gamma is a finitely presented metabelian group, then the "untwisted" fibre product or pull-back P associated to any short exact sequence 1 --> N --> Gamma --> Q --> 1 is again finitely presented. In contrast, if N and Q are abelian, then the analogous "twisted" fibre-product is not finitely presented unless F is polycyclic. Also a number of examples are constructed, including a non-finitely presented metabelian group P with H-2(P,Z) finitely generated. (C) 2003 Elsevier Science B.V. All rights reserved.
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页码:15 / 22
页数:8
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