English

On fiber cones of ${\mathfrak m}$-primary ideals

Commutative Algebra 2007-05-23 v2

Abstract

Two formulas for the multiplicity of the fiber cone F(I)=n=0In/\mInF(I)=\oplus_{n=0}^{\infty} I^n/\m I^n of an \m\m-primary ideal of a dd-dimensional Cohen-Macaulay local ring (R,\m)(R,\m) are derived in terms of the mixed multiplicity ed1(\mI),e_{d-1}(\m | I), the multiplicity e(I)e(I) and superficial elements. As a consequence, the Cohen-Macaulay property of F(I)F(I) when II has minimal mixed multiplicity or almost minimal mixed multiplicity is characterized in terms of reduction number of II and lengths of certain ideals. We also characterize Cohen-Macaulay and Gorenstein property of fiber cones of \m\m-primary ideals with a dd-generated minimal reduction JJ satisfying (i) (I2/JI)=1\ell(I^2/JI)=1 or (ii) (I\m/J\m)=1.\ell(I\m/J\m)=1.

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Cite

@article{arxiv.math/0408346,
  title  = {On fiber cones of ${\mathfrak m}$-primary ideals},
  author = {A. V. Jayanthan and Tony J. Puthenpurakal and J. K. Verma},
  journal= {arXiv preprint arXiv:math/0408346},
  year   = {2007}
}

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17 Pages