6 papers · 1 filter
Strong Converse Exponent of Quantum State Merging
Mario Berta, Hao-Chung Cheng, Roberto Rubboli +1
We determine the strong converse exponent for the entanglement cost of quantum state merging, showing that it is characterized by the optimized - conditional Rényi entropies…
Maximal Rényi Relative Entropy for
Roberto Rubboli
Quantum relative entropies play a fundamental role in quantum information theory. In the classical setting, Rényi relative entropies constitute, up to linear combinations, the most…
The strong converse exponent of composable randomness extraction against quantum side information
Roberto Rubboli, Marco Tomamichel
We find a tight characterization of the strong converse exponent for randomness extraction against quantum side information. In contrast to previous tight bounds, we employ a compo…
Additivity of quantum relative entropies as a single-copy criterion
Salman Beigi, Roberto Rubboli, Marco Tomamichel
The fundamental goal of information theory is to characterize complex operational tasks using efficiently computable information quantities, Shannon's capacity formula being the pr…
Quantum conditional entropies from convex trace functionals
Roberto Rubboli, Milad M. Goodarzi, Marco Tomamichel
We study geometric properties of trace functionals that generalize those in [Zhang, Adv. Math. 365:107053 (2020)], arising from a novel family of conditional entropies with applica…
A fixed-point algorithm for matrix projections with applications in quantum information
Shrigyan Brahmachari, Roberto Rubboli, Marco Tomamichel
We develop a fixed-point iterative algorithm that computes the matrix projection with respect to the Bures distance on the set of positive definite matrices that are invariant unde…