Stable Rank 2 Vector Bundles with Chern-Classes c1 = -1, c2 = 4.
Stable rational cohomology of automorphism groups of free groups and the integral cohomology of moduli spaces of graphs.
It is not known whether or not the stable rational cohomology groups H*(Aut(F∞);Q) always vanish (see Hatcher in [5] and Hatcher and Vogtmann in [7] where they pose the question and show that it does vanish in the first 6 dimensions). We show that either the rational cohomology does not vanish in certain dimensions, or the integral cohomology of a moduli space of pointed graphs does not stabilize in certain other dimensions. Similar results are stated for groups of outer automorphisms. This yields...
Stable splittings associated with Chevalley groups, I.
Stable splittings associated with Chevalley groups, II.
Stable Vector Bundles over the Projective Orthogonal Groups.
Stably spherical classes in the K-homology of a finite group.
State-sum invariants of knotted curves and surfaces from quandle cohomology.
Steenrod homology
Steenrod operations in subanalytic homology
Steenrod Operations in the Eilenberg-Moore Spectral Sequence.
Steenrod Squares in Cotor
Steenrod squares in the mod 2 cohomology of a finite H-space.
Steenrod's Equivariant Moore Space Problem for Cohomologically Trivial Modules.
Stiefel-Whitney characteristic classes and parallelizability of Grassmann manifolds
Stiefel-Whitney classes of the flag manifold
Stratifications of teardrops
Teardrops are generalizations of open mapping cylinders. We prove that the teardrop of a stratified approximate fibration X → Y × ℝ with X and Y homotopically stratified spaces is itself a homotopically stratified space (under mild hypothesis). This is applied to manifold stratified approximate fibrations between manifold stratified spaces in order to establish the realization part of a previously announced tubular neighborhood theory.
Stratified model categories
The fourth axiom of a model category states that given a commutative square of maps, say i: A → B, g: B → Y, f: A → X, and p: X → Y such that gi = pf, if i is a cofibration, p a fibration and either i or p is a weak equivalence, then a lifting (i.e. a map h: B → X such that ph = g and hi = f) exists. We show that for many model categories the two conditions that either i or p above is a weak equivalence can be embedded in an infinite number of conditions which imply the existence of a lifting (roughly,...
Strict modules and homotopy modules in stable homotopy.
Stripping and conjugation in the mod p Steenrod algebra and its dual.
Strong Cohomological Dimension
We characterize strong cohomological dimension of separable metric spaces in terms of extension of mappings. Using this characterization, we discuss the relation between strong cohomological dimension and (ordinal) cohomological dimension and give examples to clarify their gaps. We also show that if X is a separable metric ANR and G is a countable Abelian group. Hence for any separable metric ANR X.