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Conormal modules via Primitive ideals

Guangfeng Jiang
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Abstract

The main object of this note is to study the conormal module $M$ and the computation of the second symbolic power $\bar I^{(2)}$ of an ideal $\bar I$ in the residue ring $R/H$ of a polynomial ring $R$ over a field of characteristic zero. The torsion part $T(M)$ of $M$ and the torsion free module $M/T(M)$ are expressed by the primitive ideal of $I$ relative to $H$. Two characterizations for $M/T(M)$ to be free are proved. Some immediate applications are worked out.

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Guangfeng Jiang. 2000-01-12. Conormal modules via Primitive ideals. https://arxiv.org/abs/math/0001068

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