Suppose $X$ is a Banach space, and $E$ is a closed subspace of $X^{*}$. Can we find $F$ a closed subspace of $X$ such that $F^{**}$ can be (naturally) identified with $E^{*}$? Does it make a difference if $E$ is finite codimensional in $X^{*}$?
2026-03-26 06:34:24.1774506864
Identifying duals and second duals in Banach spaces
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