## Complexity of Bezout’s theorem. VI: Geodesics in the condition (number) metric.(English)Zbl 1175.65060

Summary: We introduce a new complexity measure of a path of (problems, solutions) pairs in terms of the length of the path in the condition metric which we define in the article. The measure gives an upper bound for the number of Newton steps sufficient to approximate the path discretely starting from one end and thus produce an approximate zero for the endpoint. This motivates the study of short paths or geodesics in the condition metric.
[For part V see M. Shub and S. Smale, Theor. Comput. Sci. 133, No. 1, 141–164 (1994; Zbl 0846.65022).]

### MSC:

 65H10 Numerical computation of solutions to systems of equations 65H04 Numerical computation of roots of polynomial equations 65H20 Global methods, including homotopy approaches to the numerical solution of nonlinear equations 65Y20 Complexity and performance of numerical algorithms 12Y05 Computational aspects of field theory and polynomials (MSC2010) 30C15 Zeros of polynomials, rational functions, and other analytic functions of one complex variable (e.g., zeros of functions with bounded Dirichlet integral)
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### References:

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