Bounded Hochschild cohomology of a Banach algebra
with coefficients in a normed Banach bimodule
is the cohomology of the Hochschild-Kamowitz
complex of bounded multilinear maps.
If
is its coboundary map, then for
The denominator is the actual image, without taking its norm closure. For , the bimodule actions are multiplication in
. The adjective bounded refers to ordinary multilinear operator norms; it does not impose complete boundedness.
The Kadison-Ringrose cohomology
conjecture concerns self-coefficients for von
Neumann algebras.