Wall's obstructions and Whitehead torsion.
Warped compact foliations
The notion of the Hausdorffized leaf space of a foliation is introduced. A sufficient condition for warped compact foliations to converge to is given. Moreover, a necessary condition for warped compact Hausdorff foliations to converge to is shown. Finally, some examples are examined.
Weak symplectic fillings and holomorphic curves
We prove several results on weak symplectic fillings of contact -manifolds, including: (1) Every weak filling of any planar contact manifold can be deformed to a blow up of a Stein filling. (2) Contact manifolds that have fully separating planar torsion are not weakly fillable—this gives many new examples of contact manifolds without Giroux torsion that have no weak fillings. (3) Weak fillability is preserved under splicing of contact manifolds along symplectic pre-Lagrangian tori—this gives many...
Wecken type problems for self-maps of the Klein bottle.
Weierstrass Points of the Universal Curve.
Weierstrass polynomials for links.
Weighted -cohomology of Coxeter groups based on barycentric subdivisons.
Weylgruppe und Momentabbildung.
What is a virtual link?
When a subset of locally lies on a sphere
When are Topologically Equivalent Orthogonal Transformations Linearly Equivalent?
When is a group homomorphism a covering homomorphism?
When projective does not imply flat, and other homological anomalies.
When ε-boundaries are manifolds
Which 3-manifold groups are Kähler groups?
The question in the title, first raised by Goldman and Donaldson, was partially answered by Reznikov. We give a complete answer, as follows: if can be realized as both the fundamental group of a closed 3-manifold and of a compact Kähler manifold, then must be finite—and thus belongs to the well-known list of finite subgroups of , acting freely on .
Which 4-manifolds are toric varieties?
Whitehead 3 is a "Slice" Link.
Whitehead doubling persists.
Whitehead Torsions Vanish in Many S1 Bundles.
Whitehead transfers for S1-bundles, an algebraic description.