Generalized Divisors and Biliaison
نویسنده
چکیده
We extend the theory of generalized divisors so as to work on any scheme X satisfying the condition S2 of Serre. We define a generalized notion of Gorenstein biliaison for schemes in projective space. With this we give a new proof of the theorem of Gaeta, that standard determinantal schemes are in the Gorenstein biliaison class of a complete intersection.
منابع مشابه
Biliaison Classes of Curves in P 3
We characterize the curves in P 3 which are minimal in their biliaison class. Such curves are exactly the curves which do no admit an elementary descending biliaison. As a consequence we have that every curve in P 3 can be obtained from a minimal one by means of a finite sequence of ascending elementary biliaisons.
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