Computational Information Geometry Wonderland

The paper:

Error Analysis of a Numerical Calculation about One-qubit Quantum Channel Capacity (ISVD'07)

investigates the numerical error in computing the Holevo channel capacity using the furthest Voronoi diagram wrt. to the von Neuman quantum divergence. They show that the error is in O(1/eps) for sampling in the latitude-longitude 1/eps points.

This algorithm allows us to study, e.g., the additivity conjecture of quantum channels.

It is a nice aspect of quantum information geometry derived from traditional computational geometry. Interestingly, the Legendre transformation for 1-qubit represented on the Bloch sphere is explicited too.