TRANSFERENCE FOR BANACH SPACE REPRESENTATIONS OF NILPOTENT LIE GROUPS. PART 1. IRREDUCIBLE REPRESENTATIONS

We establish a general CCR (liminarity) property for uniformly bounded irreducible representations of nilpotent Lie groups on reflexive Banach spaces, extending the well-known property of unitary irreducible representations of these groups on Hilbert spaces. We also prove that this conclusion fails for many representations on non-reflexive Banach spaces. Our approach to these results blends the method of transference from abstract harmonic analysis and a systematic use of spaces of smooth vectors with respect to Lie group representations.