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Let $f:X \to Y$ be a diffeomorphism between smooth complex compact manifolds. Let $\omega$ be a differential form on $Y$. It is true that the support of $f^*\omega$ is equal to $f^{-1}$ of the support of $\omega$?

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I think yes; a diffeomorphism gives you an isomorphism $h_n^{*}$ on each homology, i.e., $H^n(Y)$,$ H^n(X)$ are isomorphic as rings, vector spaces, etc. Isomorphisms preserve kernel in all "categories" I can think of. – user99680 Feb 20 '14 at 18:41
up vote 2 down vote accepted

Yes. Intuitively this is because the pullback and the preimage are the natural way to transfer forms and sets respectively across a smooth map, so you're essentially just "renaming" everything via the diffeomorphism.

If that doesn't satisfy you then the details are fairly mundane: from the definition of the pullback and the fact that every $Df_p$ is an isomorphism you get that $f^* \omega(p)$ is zero if and only if $\omega(fp)$ is. The result then follows from the fact that diffeomorphisms commute with taking closures.

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Thank you very much – user46578 Feb 21 '14 at 11:03

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