Dawar and Wilsenach (ICALP 2020) introduce the model of symmetric arithmetic circuits and show an exponential separation between the sizes of symmetric circuits for computing the determinant and the permanent. The symmetry restriction is that the circuits which take a matrix input are unchanged by a permutation applied simultaneously to the rows and columns of the matrix. Under such restrictions we have polynomial-size circuits for computing the determinant but no subexponential size circuits for the permanent. Here, we consider a more stringent symmetry requirement, namely that the circuits are unchanged by arbitrary even permutations applied separately to rows and columns, and prove an exponential lower bound even for circuits computing the determinant. The result requires substantial new machinery. We develop a general framework for proving lower bounds for symmetric circuits with restricted symmetries, based on a new support theorem and new two-player restricted bijection games. These are applied to the determinant problem with a novel construction of matrices that are bi-adjacency matrices of graphs based on the CFI construction. Our general framework opens the way to exploring a variety of symmetry restrictions and studying trade-offs between symmetry and other resources used by arithmetic circuits.
翻译:Dawar 和 Wilsenach ( ECRIP 2020) 引入了对称算术电路模型, 并显示了计算决定因素和永久的对称电路的大小之间的指数分化。 对称限制是, 矩阵输入的电路通过同时对矩阵的行和列应用的对调不改变。 在这种限制下, 我们拥有计算决定因素的多米大小电路, 但是没有用于永久的亚相色大小电路。 这里, 我们考虑了一个更为严格的对称要求, 即电路的大小不会因任意的、 甚至对行和列分别适用的对称电路而改变, 并且证明即使计算决定因素的电路也具有指数性较低的约束。 结果需要大量的新机械。 我们开发了一个总体框架, 以新的支持语标码和新的两边限制的双相色大小电路圈游戏为基础, 用来证明对称电路路线线的较低界限。 我们使用的一般框架, 开启了基于 CFI 贸易限制 和其它路路段结构 的模型 的模型, 探索了其他选择 。