Identitäten für Whitehead-Produkte höherer Ordnung.
We describe an obstruction theory for an H-space X to be a loop space, in terms of higher homotopy operations taking values in . These depend on first algebraically “delooping” the Π-algebras , using the H-space structure on X, and then trying to realize the delooped Π-algebra.
Let G be a finite loop space such that the mod p cohomology of the classifying space BG is a polynomial algebra. We consider when the adjoint bundle associated with a G-bundle over M splits on mod p cohomology as an algebra. In the case p = 2, an obstruction for the adjoint bundle to admit such a splitting is found in the Hochschild homology concerning the mod 2 cohomologies of BG and M via a module derivation. Moreover the derivation tells us that the splitting is not compatible with the Steenrod...
The class of loop spaces of which the mod cohomology is Noetherian is much larger than the class of -compact groups (for which the mod cohomology is required to be finite). It contains Eilenberg–Mac Lane spaces such as and 3-connected covers of compact Lie groups. We study the cohomology of the classifying space of such an object and prove it is as small as expected, that is, comparable to that of . We also show that X differs basically from the classifying space of a -compact group...