
doi: 10.1093/qmath/haq014
Let \(A=\ell^1(B)\) be the semigroup algebra of \(B\), the bicyclic semigroup. In [\textit{S. Bowling} and \textit{J. Duncan}, Semigroup Forum 56, No. 1, 130--145 (1998; Zbl 0910.46055)], the first simplicial cohomology group \(H^1(A,A^*)\) was shown to be isomorphic to \(\ell^\infty(\mathbb{N})\). In the paper under review, the authors give a resolution of \(\ell^\infty(B)\) which simplifies the computation of the cohomology of dual \(A\)-bimodules. This resolution is applied to show that the simplicial cohomology \(H^n(A,A^*)\) vanishes for \(n\geq 2\). It is also shown that the cyclic cohomology groups \(HC^n(A,A^*)\) vanish when \(n\) is odd and are one-dimensional when \(n\) is even (\(n\geq 2\)).
simplicial cohomology, semigroup algebra, bicyclic semigroup, Normed modules and Banach modules, topological modules (if not placed in 13-XX or 16-XX), cyclic cohomology, Structure, classification of topological algebras
simplicial cohomology, semigroup algebra, bicyclic semigroup, Normed modules and Banach modules, topological modules (if not placed in 13-XX or 16-XX), cyclic cohomology, Structure, classification of topological algebras
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 3 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Average | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
