A Practical Implementation of the Overlap Dirac Operator

A practical implementation of the overlap Dirac operator $[1+{\gamma }_5\epsilon \left(H\right)]/2\mathrm{}$ is presented. The implementation exploits the sparseness of $H$ and does not require full storage. A simple application to parity invariant three dimensional SU(2) gauge theory is carried out to establish that zero modes related to topology are exactly reproduced on the lattice.