"Partial" Fidelities
Quantum Physics
2009-10-31 v2 Mathematical Physics
math.MP
Abstract
For pairs, omega, rho, of density operators on a finite dimensional Hilbert space of dimension d I call k-fidelity the d - k smallest eigenvalues of | omega^1/2 rho^1/2 |. k-fidelities are jointly concave in omega, rho. This follows by representing them as infima over linear functions. For k = 0 known properties of fidelity and transition probability are reproduced. Partial fidelities characterize equivalence classes which are partially ordered in a natural way.
Cite
@article{arxiv.quant-ph/9912114,
title = {"Partial" Fidelities},
author = {Armin Uhlmann},
journal= {arXiv preprint arXiv:quant-ph/9912114},
year = {2009}
}
Comments
LATEX2e, 14 pages