Criteria for virtual fibering

Criteria for Virtual Fibering

We prove that an irreducible 3-manifold whose fundamental group satisfies a certain group-theoretic property called RFRS is virtually fibered. As a corollary, we show that 3-dimensional reflection orbifolds and arithmetic hyperbolic orbifolds defined by a quadratic form virtually fiber. These include the Seifert Weber dodecahedral space and the Bianchi groups. Moreover, we show that a taut sutu...

Identification of effectiveness assessment criteria for Seminary virtual courses

The main purpose of this research is to derive Seminary virtual education effectiveness criteria. Seminary education has main differences with tertiary or professional education. Therefore, to assess their effectiveness, we must take into account these differences. In this research we have used qualitative methodology and set a semi-interview mechanism with 15 experts in e-learning, all employe...

On Fibering Spheres by Toruses

Knot Adjacency and Fibering

It is known that the Alexander polynomial detects fibered knots and 3-manifolds that fiber over the circle. In this note, we show that when the Alexander polynomial becomes inconclusive, the notion of knot adjacency can be used to obtain obstructions to fibering of knots and of 3-manifolds. As an application, given a fibered knot K′, we construct infinitely many non-fibered knots that share the...

Obstructions to Fibering a Manifold

Given a map f : M → N of closed topological manifolds we define torsion obstructions whose vanishing is a necessary condition for f being homotopy equivalent to a projection of a locally trivial fiber bundle. If N = S, these torsion obstructions are identified with the ones due to Farrell [5].