Let $G$ be a simply connected compact Lie group and $\mathscr{ L}$ be the left invarinat framing of $G$. Let $\mathcal{ L}^\lambda$ be the framing obtained by twisting $\mathscr{ L}$ by a faithful representation $\lambda$. Given a torus subgroup $T''$ of $G$ we have a framing $(\mathcal{ L}^\lambda)_{ T''}$ of the quotient $G/T''$ induced from $\mathcal{ L}^\lambda$. In this note we show that under a certain dimensional condition the $e_\mathbb{ C}$-invariant of $G/T''$ with this framing provides a generator of the $J$-homomorphism or twice that. Thereby we also give a unified proof of the results for $SU(2n)$, $Spin(4n+1)$ and $Spin(8n-2)$ $(n\ge 1)$ previously proved.
Categories: math.AT