Maximal actions of finite 2-groups on ${\Bbb Z}_2$-homology 3-spheres
Tom 184 / 2004
Fundamenta Mathematicae 184 (2004), 205-221
MSC: 57M60, 57M12.
DOI: 10.4064/fm184-0-13
Streszczenie
It is known that a finite 2-group acting on a ${{\mathbb Z}}_2$-homology 3-sphere has at most ten conjugacy classes of involutions; the action of groups with the maximal number of conjugacy classes of involutions is strictly related to some questions concerning the representation of hyperbolic 3-manifolds as 2-fold branched coverings of knots. Using a low-dimensional approach we classify these maximal actions both from an algebraic and from a geometrical point of view.