David Sutter
@quantum-sutter.bsky.social
Quantum information theorist at IBM Research
Uhlmann's theorem states that the fidelity of two (mixed) states can be expressed in terms of their purifications (where the fidelity simplifies). In arxiv.org/abs/2502.01749 we generalize Uhlmann's theorem to Rényi relative entropies.
Uhlmann's theorem for relative entropies
Uhlmann's theorem states that, for any two quantum states $ρ_{AB}$ and $σ_A$, there exists an extension $σ_{AB}$ of $σ_A$ such that the fidelity between $ρ_{AB}$ and $σ_{AB}$ equals the fidelity betwe...
arxiv.org
February 5, 2025 at 6:34 AM
Uhlmann's theorem states that the fidelity of two (mixed) states can be expressed in terms of their purifications (where the fidelity simplifies). In arxiv.org/abs/2502.01749 we generalize Uhlmann's theorem to Rényi relative entropies.