characteristic class in a sentence
Examples
- The ring structure in cohomology provides the foundation for characteristic classes of fiber bundles, intersection theory on manifolds and algebraic varieties, Schubert calculus and much more.
- Indeed, several branches of mathematics, such as homology and homotopy theory, and the theory of characteristic classes were founded in order to study invariant properties of manifolds.
- In modern terms, lens spaces are determined by " simple " homotopy type, and there are no normal invariants ( like characteristic classes ) or surgery obstruction.
- In later work after the " rapprochement " of mathematics and physics, new characteristic classes were found by Simon Donaldson and Dieter Kotschick in the instanton theory.
- The obstruction to the existence of a section can often be measured by a cohomology class, which leads to the theory of characteristic classes in algebraic topology.
- In turn, the Euler class is the archetype for other characteristic classes of vector bundles, in that each " top " characteristic class equals the Euler class, as follows.
- In turn, the Euler class is the archetype for other characteristic classes of vector bundles, in that each " top " characteristic class equals the Euler class, as follows.
- The Stiefel Whitney class was named for Eduard Stiefel and Hassler Whitney and is an example of a "'Z "'/ 2 "'Z "'- characteristic class associated to real vector bundles.
- Characteristic classes were later found for foliations of manifolds; they have ( in a modified sense, for foliations with some allowed singularities ) a classifying space theory in homotopy theory.
- Since characteristic classes multiply under direct sum of vector bundles, this obstruction can be stated intrinsically in terms of the space " M " and its tangent bundle and cohomology algebra.