For a compact connected semisimple Lie group $G$ we shall prove two results (both related with Singhof's paper [13]) on the Lusternik-Schnirelmann category of the adjoint orbits of $G$, respectively the 1-dimensional relative category of a maximal torus $T$ in $G$. The techniques will be classical, but we shall also apply some basic results concerning the so-called $\mathcal A$-category (cf. [14]).
@article{118937, author = {Augustin-Liviu Mare}, title = {On two results of Singhof}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {38}, year = {1997}, pages = {379-383}, zbl = {0886.55009}, mrnumber = {1455506}, language = {en}, url = {http://dml.mathdoc.fr/item/118937} }
Mare, Augustin-Liviu. On two results of Singhof. Commentationes Mathematicae Universitatis Carolinae, Tome 38 (1997) pp. 379-383. http://gdmltest.u-ga.fr/item/118937/
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