Conservative subgroup separability for surfaces with boundary
نویسندگان
چکیده
This theorem, for F orientable and without (iii), is due to Masters and Zhang [5] and is a key ingredient in their proof that cusped hyperbolic 3–manifolds contain quasi-Fuchsian surface groups [4; 5]. Without (iii) and (iv) the theorem is a special case of well-known theorems on subgroup separability of free groups (see Hall, Jr [1]) and surface groups (see Scott [6; 7]). For a discussion of subgroup separability and 3–manifolds, see Long and Reid [3].
منابع مشابه
separability of tilings
A tiling by triangles of an orientable surfaces is called kaleidoscopic if the local reflection in any edge of a triangle extends to a global isometry of the surface. Given such a global reflection the fixed point subset of the reflection consists of embedded circles (ovals) whose union is called the mirror of the reflection. The reflection is called separating if removal of the mirror disconne...
متن کاملGeometrically continuous splines for surfaces of arbitrary topology
We analyze the space of geometrically continuous piecewise polynomial functions or splines for quadrangular and triangular patches with arbitrary topology and general rational transition maps. To define these spaces of G spline functions, we introduce the concept of topological surface with gluing data attached to the edges shared by faces. The framework does not require manifold constructions ...
متن کاملSubgroup Separability and Conjugacy Separability of Certain HNN Extensions
In this note, we give characterizations for certain HNN extensions of polycyclic-by-finite groups with central associated subgroups to be subgroup separable and conjugacy separable. We shall do this by showing the equivalence of subgroup separability and conjugacy separability in this type of HNN extensions. 2000 Mathematics Subject Classification: Primary 20E06, 20E26; Secondary 20F10, 20F19
متن کاملGeometric Implications of the Naive Bayes Assumption
A Naive (or Idiot) Bayes network is a network with a single hypothesis node and several observations that are conditionally independent given the hypothesis. We recently surveyed a number of members of the UAI community and discovered a general lack of understanding of the implications of the Naive Bayes assumption on the kinds of problems that can be solved by these networks. It has long been ...
متن کاملFinite Quotients of Rings and Applications to Subgroup Separability of Linear Groups
In this paper we apply results from algebraic number theory to subgroup separability of linear groups. We then state applications to subgroup separability of free products with amalgamation of hyperbolic 3-manifold groups.
متن کامل