Projection Methods for matrix equation AX = B

In this paper, we focus on iterative projection methods to multiple linear systems with several right-hand sides. Such situations arise, for example, in lattice quantum chromodynamics (QCD) simulations. For solving such systems efficiently, we present new block and global Krylov subspace methods which, based on a block and global Lanczos process. Numerical examples demonstrate that the new methods can be more competitive than some other block and global solvers.