Research Interests

My research area is algebraic topology. In particular, I am interested in homotopy theory. Most recently I have been pursuing two different threads in my work.

With Jeff Strom (Western Michigan University) I have been thinking about A-cellular spaces. Basically, an A-cellular space is a space that can be built out of A and its suspensions in the way that CW complexes are built out of spheres. Each space A determines a closed class - a collection of spaces which is closed under homotopy colimit operations and contains the space A. These are the so-called A-cellular spaces. Any space X can be approximated by an A-cellular space, and the measure of how difficult it is to construct this approximation is known as the A-complication of X. We have been working on developing some bounds for the A-complication of spaces. We have also been thinking about good spaces - these are spaces A such that the closed class determined by A is also closed under extensions by fibrations. In particular, we have been working to understand bounds for A-complication when A is a good space.

With Brenda Johnson (Union College) and Randy McCarthy (University of Illinois at Urbana-Champaign) I have been thinking about things relating to Goodwillie's calculus of functors. Given a functor of spaces, F, and a nice space X, there is a tower of functors, PnF, where PnF is a degree n functor. This tower acts as a Taylor tower for F, expanded around X. That is, the tower converges to the functor F in some range which depends not only on F but also on X. There are also derivatives in this theory - the nth derivative is the fibre of the map PnF --> Pn-1F. We have been studying a particular bi-complex whose homology produces the first derivative of F when F is a Gamma module in the hopes of paring down the complex while retaining the convergence to D1F.

Publications

Those papers which have not already appeared are available from the Hopf Topology archive.

The rank filtration and Robinson's complex, with Brenda Johnson and Randy McCarthy, Journal of Pure and Applied Algebra, 212 (2008) no 4 p735-752.

Homotopical Complexity and Good Spaces, with Jeff Strom, Transactions of the American Mathematical Society, 359 (2007) p687-700.

v_*-torsion spaces and thick classes with Wojciech Chacholski and William G. Dwyer, Mathematische Annalen 336 (2006) no 1, p13-26.

Model Structures on the Category of Ex-Spaces, with Mark W. Johnson, Topology and its Applications, 119 (2002) pp325-353.

The A-Complication of a Space with Wojciech Chacholski and William G. Dwyer, Journal of the London Mathematical Society, (2) 65 (2002) pp204-223.

An equivariant smash spectral sequence and unstable box product, Transactions of the American Mathematical Society 351 (1999) pp2763-2775.

An equivariant van Kampen spectral sequence, Topology and its Applications 79 (1997) pp31-48.

sign up

Return to my homepage