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Jun 30, 2012 at 19:38 comment added Mirco A. Mannucci @Asaf: I apologize for not replying (yet) to the many answers and comments on this question. My only excuse is: I was simply overwhelmed, and needed time to process the data. Rest assured, though, That I will reply to all, when digestion is complete.
Jun 28, 2012 at 17:05 comment added Asaf Karagila @Downvoter: I enjoyed the downvote, thanks! I hope you at least bothered to read the answer...
Jun 24, 2012 at 23:39 comment added David Roberts "does not have any non-trivial automorphism" what in this case is an automorphism? Given that the OP mentioned a structural viewpoint, one could imagine that a self-equivalence of the category of sets in the extension fixing the sets in the base up to isomorphism might be a more appropriate automorphism than what is usually used in (material) set theory.
Jun 24, 2012 at 9:58 comment added Stefan Geschke Andres points at something important that hasn't been stressed enough in this discussion, I think. A transitive model of set theory does not have any non-trivial automorphism. Hence the literal Galois group of a forcing extension is always trivial and in order to come up with an interesting theory it is necessary to look stabilizers of names and so on, as pointed out above.
Jun 24, 2012 at 5:53 comment added Andrés E. Caicedo "generic extensions of the same forcing need not be isomorphic." They cannot be isomorphic, unless they are equal. (By Mostowski's collapsing theorem.)
Jun 24, 2012 at 5:44 history answered Asaf Karagila CC BY-SA 3.0