发表机构
Technical University of Munich(慕尼黑工业大学)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
该研究基于矩阵小球估计、行列式权重与矩阵加权庞加莱不等式提出矩阵偏差研究新方法,得到无维度常数与高斯级数遗传小球估计,并解决了矩阵Spencer猜想。
AI 中文摘要
我们提出了一种基于矩阵小球估计的矩阵偏差研究新方法。具体而言,我们使用(由对数障碍得到的)行列式权重,将小球概率转化为倾斜高斯测度的配分函数。随后我们利用矩阵加权庞加莱不等式,将该配分函数与矩阵的收缩部分或对角部分的配分函数进行比较,得到了无维度常数。我们的技术还给出了高斯级数的遗传小球估计,该结果本身应具有独立研究价值。作为主要应用,我们解决了矩阵Spencer猜想:对于满足‖A_i‖≤1的对称n×n矩阵A₁,…,Aₙ,可以高效找到一个着色x∈{±1}ⁿ,使得‖∑ᵢ₌₁ⁿxᵢAᵢ‖=O(√n)。
英文摘要
We develop a novel approach to matrix discrepancy based on matrix small-ball estimates. Specifically, we use a determinantal weight (obtained from the log-barrier) to scale the small-ball probability into a partition function of a tilt of the Gaussian measure. We then employ matrix-weighted Poincaré inequalities to compare this partition function to that of a pinched or diagonal part of the matrix, obtaining \emph{dimension-free} constants. Our technique yields a hereditary small-ball estimate for Gaussian series that should be of independent interest. As the main application, we resolve the Matrix Spencer conjecture: for symmetric $n\times n$ matrices $A_1,\dots,A_n$ with $\|A_i\|\le1$, one can efficiently find a coloring $x\in\{\pm1\}^n$ with $\|\sum_{i=1}^n x_iA_i\|=O(\sqrt n)$.
Comments47 pages; comments and feedback welcome