Due to its optimal complexity, the multigrid (MG) method is one of the most popular approaches for solving large-scale linear systems arising from the discretization of partial differential equations. However, the parallel implementation of standard MG methods, which are inherently multiplicative, suffers from increasing communication complexity. In such cases, the additive variants of MG methods provide a good alternative due to their inherently parallel nature, although they exhibit slower convergence. This work combines the additive multigrid method with the multipreconditioned conjugate gradient (MPCG) method. In the proposed approach, the MPCG method employs the corrections from the different levels of the MG hierarchy as separate preconditioned search directions. In this approach, the MPCG method updates the current iterate by using the linear combination of the preconditioned search directions, where the optimal coefficients for the linear combination are computed by exploiting the energy norm minimization of the CG method. The idea behind our approach is to combine the $A$-conjugacy of the search directions of the MPCG method and the quasi $H_1$-orthogonality of the corrections from the MG hierarchy. In the numerical section, we study the performance of the proposed method compared to the standard additive and multiplicative MG methods used as preconditioners for the CG method.
Primal-dual interior-point multigrid method for topology optimization
University of Birmingham（伯明翰大学）；Institute of Information Theory and Automation, Academy of Sciences of the Czech Republic（捷克科学院信息论与自动化研究所）；University of Kirkuk（基尔库克大学）
An economic cascadic tensor multigrid method for solving high dimensional elliptic linear partial differential problems
Guilin University of Electronic Technology（桂林电子科技大学）；Guangxi Colleges and Universities Key Laboratory of Data Analysis and Computation（广西高校数据分析与计算重点实验室）；Center for Applied Mathematics of Guangxi (GUET)（广西应用数学中心）
Parallel Energy-Minimization Prolongation for Algebraic Multigrid
Department ICEA, University of Padova（帕多瓦大学ICEA学院）；Department of Mathematics and Statistics, University of New Mexico（新墨西哥大学数学与统计系）；Siebel Center for Computer Science, University of Illinois at Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校西贝尔计算机科学中心）
An extrapolation cascadic multigrid method combined with a fourth order compact scheme for 3D poisson equation
School of Mathematics and Statistics, Central South University（中南大学数学与统计学院）；School of Aerospace Engineering and Applied Mechanics, Tongji University（同济大学航空航天与力学学院）
Generalized preconditioned conjugate gradients for adaptive FEM with optimal complexity
Sorbonne Université, Université Paris Cité, CNRS, Laboratoire Jacques-Louis Lions（索邦大学，巴黎 Cité 大学，法国国家科学研究中心，雅克-路易·利翁斯实验室）；TU Wien, Institute of Analysis and Scientific Computing（维也纳工业大学，分析与科学计算研究所）
