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The BKK root count in \(\mathbb{C}^ n\). (English) Zbl 0855.65053

Summary: The root count developed by Bernshtein, Kushnirenko and Khovanskij (BKK root count) only counts the number of isolated zeros of a polynomial system in the algebraic torus \((\mathbb{C}^*)^n\). In this paper, we modify this bound slightly so that it counts the number of isolated zeros in \(\mathbb{C}^n\). Our bound is, apparently, significantly sharper than the recent root counts found by Rojas and in many cases easier to compute. As a consequence of our result, the Huber-Sturmfels homotopy for finding all the isolated zeros of a polynomial system in \((\mathbb{C}^*)^n\) can be slightly modified to obtain all the isolated zeros in \(\mathbb{C}^n\).

MSC:

65H10 Numerical computation of solutions to systems of equations
68W30 Symbolic computation and algebraic computation
Full Text: DOI

References:

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