In this work, we extend the robust version of the Sylvester-Gallai theorem, obtained by Barak, Dvir, Wigderson and Yehudayoff, and by Dvir, Saraf and Wigderson, to the case of quadratic polynomials. Specifically, we prove that if $\mathcal{Q}\subset \mathbb{C}[x_1.\ldots,x_n]$ is a finite set, $|\mathcal{Q}|=m$, of irreducible quadratic polynomials that satisfy the following condition: There is $\delta>0$ such that for every $Q\in\mathcal{Q}$ there are at least $\delta m$ polynomials $P\in \mathcal{Q}$ such that whenever $Q$ and $P$ vanish then so does a third polynomial in $\mathcal{Q}\setminus\{Q,P\}$, then $\dim(\text{span}({\mathcal{Q}}))=\text{poly}(1/\delta)$. The work of Barak et al. and Dvir et al. studied the case of linear polynomials and proved an upper bound of $O(1/\delta)$ on the dimension (in the first work an upper bound of $O(1/\delta^2)$ was given, which was improved to $O(1/\delta)$ in the second work).
翻译:在这项工作中,我们将巴拉克、德维尔、维格德森和叶胡道夫以及德维尔、萨拉夫和维格德森获得的Sylvester-Gallai定理仪的强效版本扩展至四面形多面体。 具体地说,我们证明,如果$\mathcal ⁇ subset\mathbb{C}[x_1.\ldots,x_n]美元是无法降价的多元二次方位数的有限集, $_mathcal1/%m美元, 满足以下条件: $\delta>0美元, 以及每美元,萨拉夫和维格德森特多面体数$至少为$\delta m$ subsupremeal 多元体数。 当Q$和美元消失时, $\mathcalcal_setminus%, 然后$\dime(maxcal_cal__x_al_al_al_al_al_al_al_al_ax_O_al_al_al_al_axxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx