Let Vk,nℂ denote the complex Steifel and Grk,nℂ the Grassmann manifolds for 1≤k<n. In this paper, we compute, in terms of the Sullivan minimal models, the evaluation subgroups and, more generally, the relative evaluation subgroups of the fibration p:Vk,k+nℂ→Grk,k+nℂ. In particular, we prove that G∗Grk,k+nℂ,Vk,k+nℂ;p is isomorphic to G∗relGrk,k+nℂ,Vk,k+nℂ;p⊕G∗Vk,k+nℂ.

Keywords: Rational homotopy theory, Sullivan minimal model, Gottlieb groups, evaluation subgroups, G-sequence, derivation