Over the last few issues, we've been talking about the math entity called a matrix. I've given examples of how matrices are useful and how matrix algebra can simplify complicated problems. A messy ...

Performing math on multidimensional arrays very efficiently. For example, the Strassen algorithm uses fast matrix math on large matrices. See multidimensional array.

All information about the system under consideration can be obtained in terms of a one-particle density matrix; and this can be constructed by an iterative method which involves only matrix algebra.