Row ideals and fibers of morphisms
نویسندگان
چکیده
منابع مشابه
Row Ideals and Fibers of Morphisms
In this note we study the fibers of a rational map from an algebraic point of view. We begin by describing two interpretations of the word ‘fiber’. Let S = k[x0, . . . , xn] be a polynomial ring over an infinite field k, I ⊂ S an ideal generated by an r+1-dimensional vector space W of forms of the same degree, and φ the associated rational map P → P = P(W ). We will use this notation throughout...
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We first provide here a very short proof of a refinement of a theorem of Kodiyalam and Cutkosky, Herzog and Trung on the regularity of powers of ideals. This result implies a conjecture of Hà and generalizes a result of Eisenbud and Harris concerning the case of ideals primary for the graded maximal ideal in a standard graded algebra over a field. It also implies a new result on the regularitie...
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ژورنال
عنوان ژورنال: Michigan Mathematical Journal
سال: 2008
ISSN: 0026-2285
DOI: 10.1307/mmj/1220879408