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Cohomogies of double covers

Let $\pi:X \rightarrow Y$ be a double cover between compact manifolds $X$, $Y$ and $\theta$ be the deck transformation. Let $H^2(X, \mathbb Z)^\theta$ be a group of $\theta^*$-invariant elements in $H^2(X, \mathbb Z)$.

My Question is:

Is $H^2(X, \mathbb Z)^\theta$ a subset of $\pi^* (H^2(Y, \mathbb Z) )$?

You can assume that $X$ is a simply-connected projective variety if necessary.

Thanks!

Basics
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  • 10
  • 14