Frame potential for finite-dimensional Banach spaces

Abstract

We define the frame potential for a Schauder frame on a finite dimensional Banach space as the square of the 2-summing norm of the frame operator. As is the case for frames for Hilbert spaces, we prove that the frame potential can be used to characterize finite unit norm tight frames (FUNTFs) for finite dimensional Banach spaces. We prove the existence of FUNTFs for a variety of spaces, and in particular that every n-dimensional complex Banach space with a 1-unconditional basis has a FUNTF of N vectors for every N≥n. However, many interesting results on FUNTFs and sums of rank-one projections for Hilbert spaces remain unknown for Banach spaces and we conclude the paper with multiple open questions.