Abstract
In this paper we investigate the nature of projections in theC *-algebras of nilpotent locally compact groups and of the associated compact open subsets in their dual spaces. We obtain explicit descriptions of all projections inL 1(G) whenG is a connected nilpotent group and inC *(G) whenG is an infinite discrete nilpotent group the torsion subgroup of which is contained in the center.
Similar content being viewed by others
References
BARNES, B.A.: The role of minimal idempotents in the representation theory of locally compact groups. Proc. Edinburgh Math. Soc. (2)23, 229–230 (1980)
BAUMSLAG, G.: Lecture notes on nilpotent groups. Providence: Amer. Math. Society 1971
BLACKADAR, B.E.:K-Theory for operator algebras, Mathematical Sciences Research Institute Publications. New York-Berlin-Heidelberg: Springer-Verlag 1986
COHEN, P.J.: On a conjecture of Littlewood and idempotent measures. Amer. J. Math.82, 191–212 (1960)
DIXMIER, J.:C *-algebras. Amsterdam: North-Holland 1981
FEICHTINGER, H.G., GRÖCHENIG, K.: A unified approach to atomic decompositions via integrable group representations. Preprint
KIRILLOV, A.A.: Unitary representations of nilpotent Lie groups. Uspekhi Mat. Nauk106, 57–110 (1962) (English translation - Russian Math. Surveys 17, 53–104 (1962))
LUDWIG, J.: Prime ideals in theC *-algebra of a nilpotent group. Monatsh. Math.101, 159–165 (1986)
MOORE, C.C.: Groups with finite dimensional irreducible representations. Trans. Amer. Math. Soc.166, 401–410 (1972)
PIMSNER, M., VOICULESCU, D.:K-groups of reduced crossed products by free groups. J. Operator Theory8, 131–156 (1982)
RICKART, C.E.: Banach algebras. Princeton: van Nostrand 1960
RIEFFEL, M.A.: Unitary representations of group extensions; an algebraic approach to the theory of Mackey and Blattner. Adv. Math. Suppl. Series4, 43–82 (1979)
ROSENBERG, J.:C *-algebras, positive scalar curvature, and the Novikov conjecture. Publ. I.H.E.S.58, 197–212 (1983)
RUDIN, W., SCHNEIDER, H.: Idempotents in group rings. Duke Math. J.31, 585–602 (1964)
TOMIYAMA, J.: Invitation toC *-algebras and dynamical systems. Singapore: World Scientific 1987
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kaniuth, E., Taylor, K.F. Projections inC *-algebras of nilpotent groups. Manuscripta Math 65, 93–111 (1989). https://doi.org/10.1007/BF01168369
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01168369