Loop spaces, twistor ${\mathbb{P}}^1$ and tempiric parameters

Abstract

We establish bijections among spherical orbits on loop symmetric spaces, principal bundles on the twistor ${\mathbb{P}}^1$, and tempiric Langlands parameters. Using Vogan's theory of minimal $K$-types, we further establish bijections among irreducible equivariant local systems on loop symmetric spaces, irreducible local systems on principal bundles on the twistor ${\mathbb{P}}^1$, and irreducible representations of all strong inner forms of the dual symmetric subgroup. The latter bijections may be viewed as a combinatorial shadow of geometric Langlands duality for real reductive groups.