We provide a new algebraic description of the structure on the set of all unstable cohomology operations for a suitable
generalised cohomology theory, $E*(–)$. Our description is as a graded and completed version of a Tall-Wraith monoid.
The $E*$-cohomology of a space $X$ is a module for this Tall-Wraith monoid. We also show that the corresponding Hopf
ring of unstable co-operations is a module for the Tall-Wraith monoid of unstable operations. Further examples are
provided by considering operations from one theory to another.
@article{1251832594,
author = {Stacey, Andrew and Whitehouse, Sarah},
title = {The hunting of the Hopf ring},
journal = {Homology Homotopy Appl.},
volume = {11},
number = {1},
year = {2009},
pages = { 75-132},
language = {en},
url = {http://dml.mathdoc.fr/item/1251832594}
}
Stacey, Andrew; Whitehouse, Sarah. The hunting of the Hopf ring. Homology Homotopy Appl., Tome 11 (2009) no. 1, pp. 75-132. http://gdmltest.u-ga.fr/item/1251832594/