Lemma 71.12.3. With hypotheses and notation as in Lemma 71.12.1 above. Assume \mathcal{A}_ d \to \mathcal{B}_ d is surjective for d \gg 0. Then
U(\psi ) = Q,
r_\psi : Q \to R is a closed immersion, and
the maps \theta : r_\psi ^*\mathcal{O}_ P(n) \to \mathcal{O}_ Q(n) are surjective but not isomorphisms in general (even if \mathcal{A} \to \mathcal{B} is surjective).
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