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On measurability of certain group actions on spaces of bounded measurable functions

Let $\mathcal{H}$ be a separable Hilbert space equipped with a strongly continuous unitary representation of a locally compact group $G$. Denote by $\mathcal{L}^{\infty}(H)$ the space of the bounded Borel measurable real valued functions on $\mathcal{H}$ (with respect to the Borel $\sigma$-algebra of the norm topology) equipped with the sup norm.

Then the representation of $G$ on $\mathcal{H}$ induces, via composition, a representation of $G$ on $\mathcal{L}^{\infty}(H)$. Given $f \in \mathcal{L}^{\infty}(H)$, set $$ \Psi_{f}(g):=g\cdot f, \quad g\in G. $$ Is the map $\Psi_{f}: G \rightarrow \mathcal{L}^{\infty}(H)$ Borel measurable?

Any reference would be greatly appreciated.

S.Z.
  • 505
  • 3
  • 12