Neumann series

The Neumann series is a mathematical tool used to find the inverse of a matrix (a grid of numbers). When directly calculating the inverse is difficult, the Neumann series approximates it by adding up an infinite sequence of terms, each refining the previous estimate. Think of it like repeatedly adjusting a guess until it nears the correct inverse. This approach works well when the matrix is close to the identity matrix (a matrix with ones on the diagonal and zeros elsewhere), ensuring the series converges and provides an accurate approximation.