Osaka Journal of Mathematics

Generic initial ideals and fibre products

Aldo Conca and Tim Römer

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We study the behavior of generic initial ideals with respect to fibre products. In our main result we determine the generic initial ideal of the fibre product with respect to the reverse lexicographic order. As an application we compute explicitly the generic initial ideal of a fibre product in a special case. We also prove that the fibre product of two graded ideals is componentwise linear if and only if both ideals have this property.

Article information

Osaka J. Math., Volume 47, Number 1 (2010), 17-32.

First available in Project Euclid: 19 February 2010

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Zentralblatt MATH identifier

Primary: 13C99: None of the above, but in this section 13P10: Gröbner bases; other bases for ideals and modules (e.g., Janet and border bases)
Secondary: 13F55: Stanley-Reisner face rings; simplicial complexes [See also 55U10]


Conca, Aldo; Römer, Tim. Generic initial ideals and fibre products. Osaka J. Math. 47 (2010), no. 1, 17--32.

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