In this paper we define new homotopy groups for topological spaces. These groups generalize the homotopy groups of Hurewicz. By the use of these groups and by improved methods we obtain new results about the ordinary homotopy groups, and also easier proofs of known results. Among other things, we can show that 76(S3) is non-trivial. 1. One of the principal problems of modern topology is to devi...

We obtain some explicit calculations of crossed Q modules induced from a crossed module over a normal subgroup P of Q By virtue of theorems of Brown and Higgins this enables the computation of the homotopy types and second homotopy modules of certain homotopy pushouts of maps of classifying spaces of discrete groups Introduction A crossed module M M P has a classifying space BM see for example ...

We investigate the following problems. Given a spherical fibration, does the Whitehead square of its homotopy Thom class vanish? If so, is the homotopy Thorn class a cyclic homotopy class?

Homotopy classes of trajectories, arising due to the presence of obstacles, are defined by the set of trajectories joining same start and end points which can be smoothly deformed into one another by gradual bending and stretching without colliding with obstacles. Despite being mostly an uncharted research area, homotopy class constraints often appear in path planning problems. For example, in ...

We provide a new and conceptually simplified construction of continuous homotopy fixed point spectra for Lubin-Tate spectra under the action of the extended Morava stabilizer group. Moreover, our new construction of a homotopy fixed point spectral sequence converging to the homotopy groups of the homotopy fixed points of Lubin-Tate spectra is isomorphic to an Adams spectral sequence converging ...

1 Rational Homotopy Theory 4 1.1 Cohomological Eilenberg-Moore Spectral Sequences . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 k-Rational Homotopy Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.3 Rational Homotopy Theory and E∞-Algebras . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.4 Differential Graded Lie Algebras . . . . . . . . . . ...

In this talk, I will first motivate the study of stable homotopy theory and introduce axiomatic frameworks that capture the salient features of the stable homotopy category. This allows one to use homotopy theoretic techniques to study areas such as algebraic geometry or modular representation theory. I will then talk about results that describe the structure of various stable homotopy categori...