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Loophole-free violations of Bell inequalities imply that at least one of the assumptions formalising local hidden-variable theories must fail. Here, the authors show that, if only one is false, then it has to fail completely, therefore excluding models that allow partial instantaneous actions at a distance, partially constrain freedom of choice or allow for partial retrocausal influences.

A loophole-free violation of Bell’s inequality with superconducting circuits shows that non-locality is a viable new resource in quantum information technology realized with superconducting circuits, promising many potential applications.

A Bell experiment that is ‘loophole’ free—leaving no room for explanations based on experimental imperfections—reveals a statistically significant conflict with local realism

Here it is shown, both theoretically and experimentally, that non-local correlations between entangled quantum particles can be used for a new cryptographic application — the generation of certified private random numbers — that is impossible to achieve classically. The results have implications for future device-independent quantum information experiments and for addressing fundamental issues regarding the randomness of quantum theory.

The nonlocality of a quantum state is often difficult to predict. Here, Cavalcanti and colleagues devise a method based on networks that makes this characterization much easier, revealing that the nonlocality of a quantum state depends on the context of the measurement.

Future quantum networks will require entangled photons operating in the telecommunications band, so they can integrate with existing architectures. Ward et al.present a quantum-dot-entangled-photon-pair source in this region and a method to measure the fidelity of a time-evolving Bell state.

A deterministic violation of the Bell inequality is reported between two superconducting circuits, providing a necessary test for establishing strong enough quantum entanglement to achieve secure quantum communications.

A study demonstrates a public generator of random numbers based on device-independent techniques, with the randomness being fully auditable and traceable.

The triangle causal structure represents a departure from the usual Bell scenario, as it should allow to violate classical predictions without the need for external inputs setting the measurement bases. Here the authors realise this scenario using a photonic setup with three independent photon sources.

A four-qubit processor of three phosphorus nuclear spins and an electron spin in silicon enables the implementation of a three-qubit Grover’s search algorithm with 95% fidelity. The implementation is based on an advanced multi-qubit gate with single-qubit gate fidelities above 99.9% and two-qubit gate fidelities above 99%.

Bell’s theorem has important implications for quantum information processing. Here the authors experimentally investigate the violation of a Bell-like inequality in the case of distant parties whose correlations are mediated by independent sources, a realistic feature in future quantum networks.

Device-independent quantum key distribution aims to distribute cryptographic keys without requiring assumptions about the quantum devices in the protocol. Here, a general security proof is reported for a class of quantum key distribution protocols, which could aid the development of highly secure encryption.

Theories of quantum gravity predict the existence of a minimal scale of length. Here the authors show that the minimal length dramatically affects dynamical observables, letting the spin operator become momentum dependent, and discuss the physical consequences of such mixing between space-time and internal degrees of freedom.

While Bell inequalities have been violated several times—mostly in photonic systems—their violations within particle physics experiments are less explored. Here, the BESIII Collaboration showcases Bell-violating nonlocal correlations between entangled hyperon pairs.

Practical implementations of quantum communication need to securely deliver information over long distances without line-of-sight. Towards this goal, Cuevas et al.use an actively stabilized interferometer to close the geometry loophole for a Bell inequality violation over 1 km of optical fibre.

The STAR experiment at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory demonstrates evidence of spin correlations in \(\Lambda \bar{\Lambda }\) hyperon pairs inherited from virtual spin-correlated strange quark–antiquark pairs during QCD confinement.

Adding tunable photon-photon nonlinearities to programmable photonic circuits would greatly extend their capabilities. Here, the authors demonstrate this by embedding a photonic-crystal waveguide nanostructure hosting an InAs quantum dot within a programmable linear optical circuit, and using it to realise a proof-of-concept quantum simulation of anharmonic molecular vibrational dynamics.

The APOE-ε4 allele is the strongest genetic risk factor for late-onset Alzheimer’s disease, but it is not deterministic. Here, the authors show that common genetic variation changes how APOE-ε4 influences cognition.

A proof-of-principle study reports a complete photonic quantum computer architecture that can, once appropriate component performance is achieved, deliver a universal and fault-tolerant quantum computer.

Fusion-based quantum computing relies on small entangled resource states that are then fused together probabilistically via linear optical circuits. Here, the authors demonstrate temporal fusion—where resource states generated at different times by the same quantum emitter are fused together—using a spin-photon interface in a quantum dot embedded in a photonic crystal waveguide.

The mechanical properties of inorganic solid electrolytes for Li batteries are typically characterised by a high Young’s modulus above 15 GPa and hardness above 1 GPa. Here, authors develop a cost-effective and mechanically compliant inorganic solid electrolyte, with reduced Young’s modulus and hardness of 1.41 and 0.22 GPa, respectively, for practical all-solid-state Li batteries.

Beck et al. develop a model where striosomes create a flexible “decision-space” that adapts to environmental context and internal state. It explains how we make choices and why decision-making varies between people, and in neuropsychiatric disorders.

The BIG Bell Test, which used an online video game with 100,000 participants worldwide to provide random bits to 13 quantum physics experiments, contradicts the Einstein–Podolsky–Rosen worldview of local realism.

As quantum information processing continues to develop apace, the need for integrated photonic devices becomes ever greater for both fundamental measurements and technological applications. To this end, Crespiet al.demonstrate a high-fidelity photonic controlled-NOT gate on a glass chip.

New types of nonlocal correlations can arise in quantum networks, but experiments have not been done for more than two independent sources. Here, the authors violate a chained n-locality inequality in a network with five nodes and four independent sources, relying only on single-qubit measurements.

Optimizing study design is critical for increasing standardized effect sizes and replicability, and the features that increase replicability in cross-sectional and longitudinal brain-wide association studies are explored.

Quantum teleportation enables the transfer of information between different systems, and will be important for building quantum computing networks. Here, the authors show teleportation of photons between two different sources with greatly differing bandwidths, with an average fidelity of 0.77.

The deep ocean is increasingly subjected to human-induced environmental change, but little is known about species-specific responses to stressors, including those from deep sea mining. This study shows that elevated temperatures and simulated sediment plumes cause physiological stress in a cosmopolitan deep-sea jellyfish, confirming the detrimental impact of seabed mining.

A Bell-like experiment that discriminates between real-number and complex-number multipartite quantum systems could disprove real quantum theory.

The CMS Collaboration reports the measurement of the spin, parity, and charge conjugation properties of all-charm tetraquarks, exotic fleeting particles formed in proton–proton collisions at the Large Hadron Collider.

Tunable interactions in quantum many-body systems have practical applications in quantum technologies. The effective spin-dependent long-range interaction known as Rydberg dressing is now exploited to entangle a pair of ultracold neutral atoms.

High-fidelity deterministic quantum state transfer and multi-qubit entanglement are demonstrated in a quantum network comprising two superconducting quantum nodes one metre apart, with each node including three interconnected qubits.

A hybrid analogue–digital quantum simulator is used to demonstrate beyond-classical performance in benchmarking experiments and to study thermalization phenomena in an XY quantum magnet, including the breakdown of Kibble–Zurek scaling predictions and signatures of the Kosterlitz–Thouless phase transition.

Noise-induced synchronization is known in classical systems and has recently been proposed in quantum many-body settings. Here, the authors experimentally demonstrate stable and entangled synchronized oscillations at the ends of a superconducting qubit chain by applying Gaussian noise to a single qubit.

Wastewater-based surveillance tends to focus on specific pathogens. Here, the authors mapped the wastewater virome from 62 cities worldwide to identify over 2,500 viruses, revealing city-specific virome fingerprints and showing that wastewater metagenomics enables early detection of emerging viruses.

Colour code on a superconducting qubit quantum processor is demonstrated, reporting above-breakeven performance and logical error scaling with increased code size by a factor of 1.56 moving from distance-3 to distance-5 code.

Donors spins in silicon are coherent, high-performance qubits, but scale-up has been challenging. Here the authors present the first experimental demonstration of exchange-based, entangling two qubit gates between electrons bound to ³¹P donors in Si.

The authors report functional and scalable long-distance quantum teleportation by teleporting a quantum state of light compatible with the telecom network onto a multimode quantum memory separated by 1km of optical fibre.

Here, Brotherton and colleagues sequence 39 mitochondrial genomes from ancient human remains. They track population changes across Central Europe and find that the foundations of the European mitochondrial DNA pool were formed during the Neolithic rather than the post-glacial period.

Interfacing quantum information between discrete and continuous would allow exploiting the best of both worlds, but it has been shown only for single-rail encoding. Here, the authors extend this to the more practical dual-rail encoding, realizing teleportation between a polarization qubit and a CV qubit.

The ALICE Collaboration provides details on the microscopic mechanism that ends up creating antideuteron in high-energy proton–proton collisions at the Large Hadron Collider.

Quantum emitters have recently been identified as efficient sources of graph states, which are entangled states crucial for photonic quantum computation. Here the authors demonstrate deterministic and reconfigurable generation of caterpillar graph states using a semiconductor quantum dot in a cavity.