We find a semi-algebraic description of the Minkowski sum \(\mathcal {A}_{3,n}\) of n copies of the twisted cubic segment \(\{(t,t^2,t^3)\mid -1\le t\le 1\}\) for each integer \(n\ge 3\). These descriptions provide efficient membership tests for the sets \(\mathcal {A}_{3,n}\). These membership tests in turn can be used to resolve some instances of the underdetermined matrix moment problem, which was formulated by Michael Rubinstein and Peter Sarnak in order to study problems related to L-functions and their zeros.

中文翻译：

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扭曲三次线段的Minkowski和的半代数性质

我们发现Minkowski求和的半代数描述\（\ mathcal {A} _ {3，N} \）的Ñ扭曲立方段的拷贝\（\ {（T，T ^ 2，T ^ 3）\每个整数 \（n \ ge 3 \）的中间-1 \ le t \ le 1 \} \）。这些描述为集合\（\ mathcal {A} _ {3，n} \）提供有效的成员资格测试 。这些隶属度测试又可以用来解决矩阵矩矩问题的某些情况，该矩阵矩问题由Michael Rubinstein和Peter Sarnak提出，目的是研究与L函数及其零相关的问题。