On the spectrum of certain subschemes of PN

AbstractWe study subschemes of PN over an algebraically closed field k which correspond to equidi-mensional Cohen-Macaulay k-algebras A such that A modulo the subalgebra generated by the elements of degree one has finite length. We show that the h-vector of these algebras satisfies a number of conditions, as suggested by the theory of the spectrum for torsion free sheaves on P3