Let $T\colon X\to Y$ be a continuous linear surjection between Frechet spaces. Then it is possible to use Michael's selection theorem to show that there exists a continuous (non-linear) function $g\colon Y\to X$ such that $g\circ T = {\rm id}_X$.

I am wondering whether it is possible to obtain a weak$\ast$-continuous counterpart of this theorem. Namely, what if $X$ and $Y$ are strong biduals of Frechet spaces and $T$ is weak*-continuous. Can we produce such a $g$ that would be weak$\ast$-continuous?

The relevant result I quoted is Corollary 7.1 in Bessaga and Pełczyński's, *Selected topics in infinite-dimensional topology*.

right inverseswhich always exist for quotient mappings between Fréchet spaces. The trivial example of the $0$ mapping $T:\mathbb R \to \{0\}$ shows that in many cases there are no left inverses. $\endgroup$ – Jochen Wengenroth Oct 5 at 6:41