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Joel David Hamkins
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Yes, from any oracle for a model $M$ of ZF, and given any poset $P$ in that model, we can compute a model for a for forcing extension $M[G]$, with $M$-generic $G\subset P$. The reason is that the oracle for $M$ includes a way for us computably to enumerate all the dense subsets of $P$ in $M$, and from that, we may computably construct an $M$-generic filter $G\subset P$, by building a descending $\omega$-sequence and selecting the first element we find in the next dense set. Given the oracle for $M$ and our computation of $G$, we can now compute equality of names relative to this filter, and thereby compute a representation of $M[G]$.

In the end, the Turing degree of the original representation of $M$ and the representation of $M[G]$ will be the same; they are computable from each other.

Joel David Hamkins
  • 236.3k
  • 44
  • 777
  • 1.4k