4 papers
Sharp continuity of quantum conditional entropy
Mario Berta, Pablo Costa Rico, Gereon Kossmann +2
We prove the sharp uniform continuity bound for quantum conditional entropy. If two bipartite states are at trace distance at most and , the optimal dimension-only m…
Routed Bell tests with arbitrarily many local parties
Gereon KoÃmann, Mario Berta, René Schwonnek
Device-independent quantum key distribution (DIQKD) promises cryptographic security based solely on observed quantum correlations, yet its implementation over long distances remain…
On approximate quantum error correction for symmetric noise
Gereon KoÃmann, Julius A. Zeiss, Omar Fawzi +1
We revisit the extendability-based semi-definite programming hierarchy introduced by Berta et al. [Mathematical Programming, 1 - 49 (2021)], which provides converging outer bounds…
Approximating fixed size quantum correlations in polynomial time
Julius A. Zeiss, Gereon KoÃmann, Gereon Koßmann +2
We show that -additive approximations of the optimal value of fixed-size two-player free games with fixed-dimensional entanglement assistance can be computed in time $…