Progress on the Kretschmann-Schlingemann-Werner Conjecture
(pp1319-1330)
Frederik vom Ende
doi:
https://doi.org/10.26421/QIC23.15-16-5
Abstracts:
Given any pair of quantum channels
$\Phi_1,\Phi_2$
such that at least one of them has
Kraus
rank one, as well as any respective
Stinespring
isometries $V_1,V_2$,
we prove that there exists a unitary
$U$ on
the environment such that
$\|V_1-(\mathbbm1\otimes U)V_2\|_\infty\leq\sqrt{2\|\Phi_1-\Phi_2\|_\diamond}$.
Moreover, we provide a simple example which shows that the factor
$\sqrt2$
on the right-hand side is optimal, and we conjecture that this
inequality holds for every pair of channels.
Key Words:
Stinespring dilation,
Stinespring
isometries, quantum channels,
diamond norm |