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Quantum-mechanical predictions are generally probabilistic. Here, assuming freely chosen measurements, it is shown that enhanced predictions are not possible and, thus, randomness is inherent in quantum theory: a result that has applications in fields such as quantum cryptography.

Developments in quantum cryptography show that it is possible to protect secrets — from those with superior technology, those who profess to provide our security and even those who manipulate us without our knowledge — under surprisingly weak assumptions.

Although they offer significant promise, practical implementations of quantum key distribution are often not as rigorous as theory predicts. This study demonstrates how two instances of such discrepancies can be resolved by taking advantage of an enotropic formulation of the uncertainty principle.

Information theory was originally developed to study the fundamental limits of telecommunication. But thanks to recent extensions it can now also be applied to solid-state physics.

Analysis of ground-sourced and satellite-derived models reveals a global forest carbon potential of 226 Gt outside agricultural and urban lands, with a difference of only 12% across these modelling approaches.

Logic gates are the elementary building blocks of computers. The finding that a single logic gate may drive a refrigerator is a beautiful demonstration that information-processing devices can have useful thermodynamic properties.

The Heisenberg uncertainty principle bounds the uncertainties about the outcomes of two incompatible measurements on a quantum particle. This bound, however, changes if a memory device is involved that stores quantum information. New work now extends the uncertainty principle to include the case of quantum memories, and should provide a guide for quantum information applications.

Bell’s equations enable scientists to test the fundamental implications of quantum physics. A central tenet of this idea is that the choice of measurement is truly random. Researchers now show that some Bell experiments can even increase randomness in cases where choice is not entirely free. The concept could increase the usefulness of weakly random sources for more thorough tests of quantum mechanics.

Quantum mechanics is expected to provide a consistent description of reality, even when recursively describing systems contained in each other. Here, the authors develop a variant of Wigner’s friend Gedankenexperiment where each of the current interpretations of QM fails in giving a consistent description.

Irreversible computation cannot be performed without a work cost, and energy dissipation imposes limitations on devices' performances. Here the authors show that the minimal work requirement of logical operations is given by the amount of discarded information, measured by entropy.

Storage of information, in any form, relies on patterns standing out from thermal fluctuations. In this work, the authors highlight a fundamental tradeoff quantifying the minimum amount of nonequilibrium resources needed to achieve a target level of accuracy in the processing of information.

Security proofs against general attacks are the ultimate goal of QKD. Here, the authors show how the Generalised Entropy Accumulation Theorem can be used, for some classes of QKD scenarios, to translate security proofs against collective attacks in the asymptotic regime into proofs against general attacks in the finite-size regime.

Integrating inventory data with machine learning models reveals the global composition of tree types—needle-leaved evergreen individuals dominate, followed by broadleaved evergreen and deciduous trees—and climate change risks.

The security of DIQKD is difficult to prove, as one needs to take into account every possible attack strategy. Here, the authors develop a method to determine the entropy of a system as the sum of the entropies of its parts. Applied to DIQKD, this implies that it suffices to consider i.i.d. attacks.