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Norm for pointwise convergence

Let $V=C([0,1],\mathbf{R})$ be the vector space of continuous real-valued functions on $[0,1]$.

Let $(f_n)$ be a sequence in $V$. Then $(f_n)$ converges with respect to the max-norm on $V$ if and only if $(f_n)$ is uniformly convergent.

As a consequence, since the limit of a uniformly convergent sequence in continuous, we conclude that $V$ endowed with the max-norm is a Banach space.

Now, on $V$ there is also a notion of pointwise convergence. Is there a norm $\Vert \cdot \Vert_{pc}$ on $V$ such that a sequence $(f_n)$ in $V$ converges with respect to $\Vert \cdot\Vert_{pc}$ if and only if $(f_n)$ is pointwise convergent?

Note that $V$ will not be Banach under this norm.

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    That anwers my question. Should have looked around a bit more carefully. So there is no norm on $V$ in which convergence is pointwise convergence.2011-10-19
  • 0
    No problem, and welcome to Math Stackexchange.2011-10-19

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