Kronecker与Newton求解方法：首次比较

Backtracking New Q-Newton's method: a good algorithm for optimization and solving systems of equations

In this paper, by combining the algorithm New Q-Newton's method - developed in previous joint work of the author - with Armijo's Backtracking line search, we resolve convergence issues encountered by Newton's method (e.g. convergence to a saddle point or having attracting cycles of more than 1 point) while retaining the quick rate of convergence for Newton's method. We also develop a family of such methods, for general second order methods, some of them having the favour of quasi-Newton's methods. The developed algorithms are very easy to implement. From a Dynamical Systems' viewpoint, the new…

稀疏多项式求解的复杂性：在紧致化托里奇流形上的同调及条件度量

Complexity of sparse polynomial solving: homotopy on toric varieties and the condition metric

本文研究了通过同调持续法求解稀疏多项式方程组的成本。首先，通过n个单项基确定n元多项式方程组的空间。这些系统的根的自然定位是某种托里奇流形。该流形是依赖于单项基的$(\mathbb C\setminus\{0\})^n$的紧致化。在该托里奇流形上定义了托里奇牛顿算子。Smale的alpha理论被推广以提供二次收敛的标准。定义了两个条件数并在此设定中获得了高阶导数估计。牛顿算子和相关的条件数在与动量映射相关的群作用下保持不变。给出了一个同调算法，并证明其在提升的同调路径的条件长度上线性终止。这扩展了Shub（2009）的结果。