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Igor Belegradek
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What's wrong with compact-open topology on the space of maps?

Given a smooth vector bundle $E$ with non-compact base, let $\Gamma(E)$ be the space of $C^\infty$ sections equipped with compact-open $C^\infty$-topology.

  1. I have heard that $\Gamma(E)$ is not locally-contractible. Why not?

  2. Is $\Gamma(E)$ contractible? Visibly any section can be joined to the zero section by "straight line", doesn't this prove that $\Gamma(E)$ is contractible?

  3. Is it true that every convex subset of $\Gamma(E)$ is contractible? The argument of 2 seems to apply, but then it seems plausible that each section has an arbitrary small convex neighborhood, contradicting 1.

Igor Belegradek
  • 29.1k
  • 2
  • 80
  • 176