A Non-Regular Grobner Fan
نویسنده
چکیده
The Gröbner fan of an ideal I ⊂ k[x1, . . . , xn], defined by Mora and Robbiano, is a complex of polyhedral cones in Rn. The maximal cones of the fan are in bijection with the distinct monomial initial ideals of I as the term order varies. If I is homogeneous the Gröbner fan is complete and is the normal fan of the state polytope of I. In general the Gröbner fan is not complete and therefore not the normal fan of a polytope. We may ask if the restricted Gröbner fan, a subdivision of Rn≥0, is regular i.e. the normal fan of a polyhedron. The main result of this paper is an example of an ideal in Q[x1, . . . , x4] whose restricted Gröbner fan is not regular.
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ورودعنوان ژورنال:
- Discrete & Computational Geometry
دوره 37 شماره
صفحات -
تاریخ انتشار 2007