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Strong converse for identification via quantum channels
We present a simple proof of the strong converse for identification via discrete memoryless quantum channels, based on a novel covering lemma. The new method is a generalization to quantum
Distillation of secret key and entanglement from quantum states
  • I. Devetak, A. Winter
  • Computer Science
    Proceedings of the Royal Society A: Mathematical…
  • 11 June 2003
A coding theorem is proved to achieve the ‘wire–tapper’ bound, the difference of the mutual information Alice–Bob and that of Alice–Eve, for so–called classical–quantum-quantum–correlations, via one–way public communication, which yields information–theoretic formulae for the distillable secret key.
Operational Resource Theory of Coherence.
An operational theory of coherence (or of superposition) in quantum systems is established, by focusing on the optimal rate of performance of certain tasks, by demonstrating that the coherence theory is generically an irreversible theory by a simple criterion that completely characterizes all reversible states.
“Squashed entanglement”: An additive entanglement measure
A new entanglement monotone for bipartite quantum states is presented, inspired by the so-called intrinsic information of classical cryptography and is given by the halved minimum quantum conditional mutual information over all tripartite state extensions: it is convex, additive on tensor products, and superadditive in general.
Information causality as a physical principle
It is suggested that information causality—a generalization of the no-signalling condition—might be one of the foundational properties of nature and help to distinguish physical theories from non-physical ones.
Entanglement and the foundations of statistical mechanics
Statistical mechanics is one of the most successful areas of physics. Yet, almost 150 years since its inception, its foundations and basic postulates are still the subject of debate. Here we suggest
Strong Converse for the Classical Capacity of Entanglement-Breaking and Hadamard Channels via a Sandwiched Rényi Relative Entropy
It is shown that a strong converse theorem holds for the classical capacity of all entanglement-breaking channels and all Hadamard channels (the complementary channels of the former) that the probability of correctly decoding a classical message converges exponentially fast to zero in the limit of many channel uses if the rate of communication exceeds the classical Capacity.
Structure of States Which Satisfy Strong Subadditivity of Quantum Entropy with Equality
We give an explicit characterisation of the quantum states which saturate the strong subadditivity inequality for the von Neumann entropy. By combining a result of Petz characterising the equality
Coding theorem and strong converse for quantum channels
  • A. Winter
  • Computer Science
    IEEE Trans. Inf. Theory
  • 1 November 1999
A new proof of Holevo's (1973, 1977) coding theorem for transmitting classical information through quantum channels, and its strong converse is presented, largely inspired by Wolfwitz's combinatorial approach using types of sequences.
Quantum mechanical evolution towards thermal equilibrium.
It is proved, with virtually full generality, that reaching equilibrium is a universal property of quantum systems: almost any subsystem in interaction with a large enough bath will reach an equilibrium state and remain close to it for almost all times.