Kédim, Imed; Hatem, Megdiche On the cortex of a nilpotent Lie group. (Sur le cortex d’un groupe de Lie nilpotent.) (French. English summary) Zbl 1170.22004 J. Math. Kyoto Univ. 49, No. 1, Article ID 8, 161-172 (2009). Summary: Let \(G\) be a connected and simply connected, nilpotent Lie group. In this paper, we show that the cortex of \(G\) is a semi-algebraic set by means of a geometric characterization. It is also shown that the cortex is the image under a linear projection of a countable union of semi-algebraic sets lying in the tensor product \(T(\mathfrak{g})\otimes\mathfrak{g}\)*. Cited in 2 Documents MSC: 22E27 Representations of nilpotent and solvable Lie groups (special orbital integrals, non-type I representations, etc.) 22E25 Nilpotent and solvable Lie groups PDFBibTeX XMLCite \textit{I. Kédim} and \textit{M. Hatem}, J. Math. Kyoto Univ. 49, No. 1, Article ID 8, 161--172 (2009; Zbl 1170.22004)