The Relative Proj Construction
نویسنده
چکیده
Earlier we defined the Proj of a graded ring. In these notes we introduce a relative version of this construction, which is the Proj of a sheaf of graded algebras S over a scheme X. This construction is useful in particular because it allows us to construct the projective space bundle associated to a locally free sheaf E , and it allows us to give a definition of blowing up with respect to an arbitrary sheaf of ideals.
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