In this paper, we elaborate on Connes’ proof of the integrality of the trace conjecture for free groups, in order to show that any action of a group G on a tree leads to a similar integrality assertion concerning the trace on the group algebra ℂG, which is associated with the set of group elements that stabilize a vertex.
Cite this article
Ioannis Emmanouil, Group splittings and integrality of traces. Comment. Math. Helv. 84 (2009), no. 1, pp. 171–187DOI 10.4171/CMH/157