AI 中文总结
该研究在$\boldsymbol{\rm \bf C}^6$中构造19个高斯整数项向量实现相位恢复,将6维最小相位恢复测量数的上界降至19,结合已知下界得其为18或19,且通过精确有理计算完成认证。
AI 中文摘要
我们展示了$\boldsymbol{\rm \bf C}^6$中19个具有高斯整数项的显式向量,它们可用于相位恢复:强度$|\boldsymbol{\rm \bf \text{⟨}}a_j,x\boldsymbol{\rm \bf \text{⟩}}|^2$($j=1,\boldsymbol{\rm \bf \text{…}},19$)能确定$\boldsymbol{\rm \bf C}^6$中的每个$x$,仅相差一个模为1的标量。这给出$m_{\boldsymbol{\rm \bf C}}(6)\boldsymbol{\rm \bf ≤}19=4d-5$,比通用计数$4d-4$少1;结合Wang和Xu给出的下界$m_{\boldsymbol{\rm \bf C}}(6)\boldsymbol{\rm \bf ≥}18$,6维空间中的最小测量数为18或19。该结论通过精确的有理计算验证,且可归档并重复运行:经基础约化后,相位恢复等价于5个5元二次方程构成的方程组的实零点集为空,该方程组的归档消元式是一个无实根的14次无平方因子整系数多项式。
英文摘要
We exhibit nineteen explicit vectors in $\mathbb{C}^6$, with Gaussian-integer entries, that do phase retrieval: the intensities $|\langle a_j,x\rangle|^2$, $j=1,\dots,19$, determine every $x\in\mathbb{C}^6$ up to a unimodular scalar. This gives $m{\mathbb{C}}(6)\le 19=4d-5$, one below the generic count $4d-4$; combined with the lower bound $m{\mathbb{C}}(6)\ge 18$ of Wang and Xu, the minimal measurement number in dimension six is 18 or 19. The claim is verified by an exact rational computation, archived and rerunnable: after an elementary reduction, phase retrieval is equivalent to the emptiness of the real zero set of a system of five quadratic equations in five unknowns, and the archived eliminant of that system is a squarefree integer polynomial of degree fourteen with no real roots.