论文标题

关于代数自然证明的存在

On the Existence of Algebraic Natural Proofs

论文作者

Chatterjee, Prerona, Kumar, Mrinal, Ramya, C, Saptharishi, Ramprasad, Tengse, Anamay

论文摘要

代数自然证明的框架是在《福布斯》,《什皮尔卡和沃尔克》(2018年)的作品中独立引入的。我们使用代数硬度和伪随机性之间的已知连接,对与此框架有关的问题提供了更多的启示,如下所示。 1。$ \ Mathsf {VP} $的子类,包含具有有限系数的多项式族的子类具有有效的方程。在有限的字段上,该结果无需任何限制系数。此外,这两个结果都扩展到\ emph {Any}类,该类允许允许低变化的低度通用图:类中所有多项式的生成器。大多数研究的课程都有此属性,例如\ textsf {vnp},\ textsf {vbp},\ textsf {vf}。 2。在特征零的字段上,$ \ mathsf {vnp} $没有任何有效的方程,如果代数电路的永久性很难成倍。此外,从近似意义上讲,永久性的指数硬度甚至排除了大大程度的有效方程。这给出了唯一已知的``自然''下限技术(根据可信的硬度假设)的障碍,并且还表明,对于$ \ sathsf {vnp} $,对第一类结果中系数的限制是必不可少的。 第一组结果基本上是通过代数化非平凡击球集产生硬度的众所周知的方法(例如Heintz and Schnorr 1980)。 $ \ Mathsf {VNP} $方程的条件硬度使用的事实是,针对班级的伪随机性可以从该类(足够难以)的类别中提取(Kabanets和Impagliazzo,2004)。

The framework of algebraically natural proofs was independently introduced in the works of Forbes, Shpilka and Volk (2018), and Grochow, Kumar, Saks and Saraf (2017), to study the efficacy of commonly used techniques for proving lower bounds in algebraic complexity. We use the known connections between algebraic hardness and pseudorandomness to shed some more light on the question relating to this framework, as follows. 1. The subclass of $\mathsf{VP}$ that contains polynomial families with bounded coefficients, has efficient equations. Over finite fields, this result holds without any restriction on coefficients. Further, both these results extend to \emph{any} class that admits a low-variate, low-degree universal map: a generator for all polynomials in the class. Most well-studied classes have this property, e.g. \textsf{VNP}, \textsf{VBP}, \textsf{VF}. 2. Over fields of characteristic zero, $\mathsf{VNP}$ does not have any efficient equations, if the Permanent is exponentially hard for algebraic circuits. Moreover, exponential hardness of the Permanent in the approximative sense, even rules out efficient equations of large degree. This gives the only known barrier to ``natural'' lower bound techniques (that follows from believable hardness assumptions), and also shows that the restriction on coefficients in the first category of results about $\mathsf{VNP}$ is necessary. The first set of results follows essentially by algebraizing the well-known method of generating hardness from non-trivial hitting sets (e.g. Heintz and Schnorr 1980). The conditional hardness of equations for $\mathsf{VNP}$ uses the fact that pseudorandomness against a class can be extracted from a polynomial that is (sufficiently) hard for that class (Kabanets and Impagliazzo, 2004).

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源