Lower Bounds in Real Algebraic Geometry and Orientability of Real Toric Varieties
نویسندگان
چکیده
The real solutions to a system of sparse polynomial equations may be realized as a fiber of a projection map from a toric variety. When the toric variety is orientable, the degree of this map is a lower bound for the number of real solutions to the system of equations. We strengthen previous work by characterizing when the toric variety is orientable. This is based on work of Nakayama and Nishimura, who characterized the orientability of smooth real toric varieties.
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عنوان ژورنال:
- Discrete & Computational Geometry
دوره 50 شماره
صفحات -
تاریخ انتشار 2013