Measure, Integration & Real Analysis · Problem 6E.14

L^p Spaces — Sheldon Axler

Mathematics — Measure Theory · bounded-inverse-theorem-v-not-banach

Problem

Show that there exists a normed space VV, a Banach space WW, and a one-to-one bounded linear map TT of VV onto WW such that T−1T^{-1} is not a bounded linear map of WW onto VV. [This exercise shows that the hypothesis in the Bounded Inverse Theorem (6.83) that VV is a Banach space cannot be relaxed to the hypothesis that VV is a normed vector space.]

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