Algebraische und topologische reelle Zykeln unter birationalen Transformationen.
Algebras of the cohomology operations in some cohomology theories [Book]
Algebroid nature of the characteristic classes of flat bundles
The following two homotopic notions are important in many domains of differential geometry: - homotopic homomorphisms between principal bundles (and between other objects), - homotopic subbundles. They play a role, for example, in many fundamental problems of characteristic classes. It turns out that both these notions can be - in a natural way - expressed in the language of Lie algebroids. Moreover, the characteristic homomorphisms of principal bundles (the Chern-Weil homomorphism [K4], or the...
Algorithms for Nielsen type periodic numbers of maps with remnant on surfaces with boundary and on bouquets of circles I
In this paper and its sequel we present a method that, under loose restrictions, is algorithmic for calculating the Nielsen type numbers NΦₙ(f) and NPₙ(f) of self maps f of hyperbolic surfaces with boundary and also of bouquets of circles. Because self maps of these surfaces have the same homotopy type as maps on wedges of circles, and the Nielsen periodic numbers are homotopy type invariant, we need concentrate only on the latter spaces. Of course the results will then automatically apply...
Allgemeine Lage und äquivariante Homotopie.
Almost transitive actions on spaces with the rational homotopy of sphere products.
An abstract setting for homotopy pushouts and pullbacks
An acyclic extension of the braid group.
An algebraic method for calculating the topological degree
An Algebraic Model for G-Simple Homotopy Types.
An algebraic model for homotopy fibers.
An algebraic model of fibration with the fiber -space.
An analogue of convexity for complements of amoebas of varieties of higher codimension, an answer to a question asked by B. Sturmfels.
An Application of the Stiefel-Whitney Classes to the Proof of a Fixed Point Theorem for Set-Valued Mappings
We prove a fixed point theorem for Borsuk continuous mappings with spherical values, which extends a previous result. We apply some nonstandard properties of the Stiefel-Whitney classes.
An approach to shape covering maps.
In this note we give an approach to shape covering maps which is comparable to that of *-fibrations (Mardesic and Rushing (1978)). The introduced notion conserves some important properties of usual covering maps.
An Arithmetic Characterization of the Rational Homotopy Groups of Certain Spaces.
An effective criterion for the existence of a mass partition
An Efficient Degree-Computation Method for a Generalized Method of Bisection.
An exact sequence from the nth to the (n-1)-st fundamental group
An Exact Sequence of Braid Groups.