Isometries of infinite dimensional Hilbert geometries
  In this paper we extend results by De la Harpe concerning the isometries of strictly convex Hilbert geometries, and the characterisation of the isometry groups of Hilbert geometries on finite dimensional simplices, to infinite dimensions. The proofs rely on a mix of geometric and functional analytic methods. 
Bas Lemmens, Mark Roelands, and Marten Wortel
math.MG math.FA