On a function on the mapping class group of a surface of genus 2
β Scribed by Ryoji Kasagawa
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 184 KB
- Volume
- 102
- Category
- Article
- ISSN
- 0166-8641
No coin nor oath required. For personal study only.
β¦ Synopsis
We study representations of subgroups of the mapping class group M g of a surface of genus g 2 arising from the actions of them on the first cohomology groups of the surface with local coefficient systems which are defined by nontrivial homomorphisms Ο 1 (Ξ£ g , * ) β Z 2 = Aut(Z). As an application, in the case of g = 2, we construct a function on M 2 which agrees with the Meyer function Ο : M 2 β Q on the Torelli group J 2 .
π SIMILAR VOLUMES
## Abstract This Note announces two results on the genus of a group. First, there is exactly one group of genus two, thus answering a question of V. K. Proulx. Second, the genus of the full symmetric group of degree __n__ is __n__!/168 + 1, for all __n__ > 167.
Let T be an integral domain, I a nonzero proper ideal of T , and ' : T β T=I the natural projection. For an integral domain D which is a proper subring of T=I , R = ' -1 (D) is then a subring of T . We investigate the class group Cl(R), the Picard group Pic(R), and the local class group G(R) of the
Partially supported by the research funds of Ministero dell'Uni¨ersita e della Ricerca Scientifica e Tecnologica and by Grant 9300856.CT01 of Consiglio Nazionale delle Ricerche.