O existenci homeomorfního zobrazení Gaussovy roviny na sebe převádějícím danou elementární křivku na křivku po částech lineární
O zborcené ploše, jejíž část je topologicky ekvivalentní s Möbiovým listem
O(2) action on the 5-sphere.
Observability of control systems for polynomial inputs and genericity
We consider smooth single-input, two-output systems on a compact manifold X. We show that the set of systems that are observable for any polynomial input whose degree is less than or equal to a given bound contains an open and dense subset of the set of smooth systems.
Obstruction Theory in Fiber Spaces.
Obstructions for Clifford Structures on Vector Bundles.
Obstructions to Embedding and Isotopy in the Metastable Range.
Obstructions to the existence of monotone Lagrangian embeddings into cotangent bundles of manifolds fibered over the circle
We extend the constructions and results of Damian to get topological obstructions to the existence of closed monotone Lagrangian embeddings into the cotangent bundle of a space which is the total space of a fibration over the circle.
Octahedral Noncompact Hyperbolic Space Forms With Finite Volume
Of Torus and Turk's-Head Knots: A Polar Trigonometric Modeling
Om multiple points of smooth immersions.
On 10-crossing knots
On 2-cycles of which are represented by foliated -bundles over
We give several sufficients conditions for a 2-cycle of Diff (resp. Diff) represented by a foliated -(resp. -) bundle over a 2-torus to be homologous to zero. Such a 2-cycle is determined by two commuting diffeomorphisms , of (resp. ). If , have fixed points, we construct decompositions: , , where the interiors of Supp Supp are disjoint, and and belong either to ( Diff) or to a one-parameter subgroup generated by a -vectorfield . Under some conditions on the norms...
On 2-distributions in 8-dimensional vector bundles over 8-complexes
It is shown that the -index of a 2-distribution in an 8-dimensional spin vector bundle over an 8-complex is independent of the 2-distribution. Necessary and sufficient conditions for the existence of 2-distributions in such vector bundles are given in terms of characteristic classes and a certain secondary cohomology operation. In some cases this operation is computed.
On 3-dimensional Lie algebras of vector fields
On 3-manifold invariants arising from finite-dimensional Hopf algebras.
On 3-Manifolds with Finite Solvable Fundamental Groups.
On 4-fields and 4-distributions in 8-dimensional vector bundles over 8-complexes
Let ξ be an oriented 8-dimensional spin vector bundle over an 8-complex. In this paper we give necessary and sufficient conditions for ξ to have 4 linearly independent sections or to be a sum of two 4-dimensional spin vector bundles, in terms of characteristic classes and higher order cohomology operations. On closed connected spin smooth 8-manifolds these operations can be computed.
On 4-fold covering moves.
On 4-manifolds and span-related numbers for cat manifolds.