Simulating electrochemical interfaces under an applied voltage requires a grand-canonical treatment of electrons, yet standard machine-learning potentials (MLPs) are canonical or rely on electronic-property supervision. We introduce a thermodynamically consistent constant-potential MLP (TCCP-MLP) trained solely on energies and forces. The work function emerges as the exact derivative of a unified energy functional, capturing long-range electrostatics and charge transfer. We demonstrate TCCP-MLP by predicting voltage-dependent activation barriers and charge transfer for C-C coupling on the Cu (100) surface.

Liquid foams are archetypal athermal amorphous solids whose elasticity arises from the jamming of densely packed bubbles. We investigate the stress relaxation of nonaging liquid foams following flow cessation, using fast x-ray tomorheoscopy. Thanks to in situ, time-resolved measurements, we uncover robust linear affine relationships between shear stress, plastic activity, and coordination number throughout the relaxation toward a residual stress state below the yield value. In contrast to previous studies on amorphous solids, we observe an exponential relaxation governed by the duration of individual plastic events, rather than by cascades of correlated ones associated with much longer, shear-rate-dependent timescales or power-law relaxations. Our results provide new insight into the microscopic mechanisms governing the time evolution of stress in jammed amorphous solids.

Determining the fundamental limits of nonlinear functionals of quantum measurement statistics is a crucial yet generally intractable nonconvex optimization problem. We introduce a generic support-function-based outer-approximation framework for solving concave-minimization (or convex-maximization) problems over the quantum state space. By mapping the problem onto a reduced $\mathcal{Z}$ space, we characterize the exact quantum boundary through supporting half spaces derived from the largest eigenvalues of effective observables. This yields an effective method that produces tight bounds for general measurements in finite-dimensional quantum systems with preassigned numerical precision. As an initial application, we recover the exact variance-based uncertainty relations of Schwonnek et al. [State-independent uncertainty relations and entanglement detection in noisy systems, Phys. Rev. Lett. 119, 170404 (2017)] and efficiently compute optimal entropic uncertainty relations (EURs). Our results reveal that standard analytical and majorization-based EUR bounds are fundamentally loose for generic measurements, and we show that the resulting certified bounds directly enhance quantum steering detection under asymmetric settings. We further apply the framework to determine the maximal athermality resource certifiable from a restricted measurement scenario. Our method thus provides a universal computational tool for exploring the boundaries of quantum state space and the limits of quantum resources.

Understanding mechanisms for the breakdown of thermalization in closed quantum systems is a central problem in quantum many-body physics. We demonstrate strong nonergodic behavior in the XX model on coupled chains, where domain-wall initial states retain an inhomogeneous magnetization profile for arbitrarily long times. We find that this effect arises due to zero modes protected by chiral symmetry. Using an analysis based on the Lanczos algorithm, we identify evidence for a localization transition in the thermodynamic limit at a critical coupling between the chains. We further show that antiferromagnetic defects in the initial state and symmetry-breaking perturbations restore slow thermalization, whereas it remains robust for symmetry-conserving perturbations. These results establish that degenerate, symmetry-protected subspaces can give rise to thermodynamically stable nonergodic dynamics in experimentally accessible quantum systems.

Quantum batteries provide a setting to investigate whether quantum effects can enhance the rate of energy storage beyond classical limits. While superextensive charging power has been reported in a few models, the fundamental physical requirements for achieving such scaling remain unclear. Here we identify the growth with system size of the $g$-extensiveness of either the battery or charging Hamiltonian as a necessary condition for achieving superextensive charging power in direct-charging protocols. We prove that bounded $g$-extensiveness forbids superextensive power, irrespective of interaction order. This criterion also explains why many previously studied protocols fail to exhibit superextensive behavior despite involving interactions with large participation numbers. Crucially, we demonstrate that global operations are not necessary: superextensive power can be achieved using Hamiltonians of fixed interaction order that remain energy extensive, provided $g$-extensiveness grows with system size. We illustrate this mechanism using a modified central-spin model.

Quantum simulation is a promising pathway toward practical quantum advantage by simulating large-scale quantum systems. In this Letter, we propose communication-efficient distributed quantum simulation protocols by exploring three quantum simulation algorithms, including the product formula, the truncated Taylor series, and quantum signal processing over a quantum network. Crucially, our protocols significantly reduce the local hardware requirements of individual quantum processing units while ensuring the overall gate complexity does not exceed that of standard monolithic architectures. Our protocols are further shown to be optimal by deriving a lower bound on the quantum communication complexity for distributed quantum simulations with respect to evolution time and the number of distributed quantum processing units. Additionally, our distributed techniques go beyond quantum simulation and are applied to distributed versions of Grover’s algorithm and quantum phase estimation. Our work not only paves the way for achieving a practical quantum advantage by scalable quantum simulation but also enlightens the design of more general distributed architectures across various physical systems for quantum computation.

High-precision optical phase stabilization in quantum networks is fundamentally constrained by the strict photon-flux and duty-cycle limits required to avoid disturbing fragile quantum states. This challenge becomes especially critical when coordinating multiple independent light sources for multistep quantum protocols. Here, we develop an integrated phase-stabilization framework that incorporates a Bayesian phase estimator to optimally extract information from sparse single-photon detection events. This approach outperforms conventional maximum-likelihood estimation and achieves the shot-noise limit under minimal photon flux. The framework enables real-time correction of combined phase noise from both nodal lasers and transmission fibers, facilitating a two-step excitation protocol for heralded entanglement generation between separate trapped-ion nodes via single-photon interference. Operating with a detected photon rate of $\sim 1\mathrm{MHz}$ and a duty cycle $\le 6.5\%$, the system maintains interferometric visibility $>97\%$ over fiber links of 10 km and 100 km. This phase control yields long-lived ion-ion entanglement with parity contrast exceeding 85%, enabling device-independent quantum key distribution with finite-size security analysis over 10 km and a positive asymptotic key-rate over 100 km. Moreover, the resulting memory-memory entanglement at 10 km survives beyond the average time required to establish it—a fundamental requirement for quantum repeaters. This Letter establishes a robust and scalable foundation for practical long-distance quantum networks.

Black hole static Love numbers vanish, but their dynamical counterparts do not. We present the entire scheme-independent dynamical response ${\overline{\mathcal{F}}}_{\ell ,s}$ of a Schwarzschild black hole in closed form, to all orders in $G$, and for every spin $s$ and multipole $\ell$. The result is ${\overline{\mathcal{F}}}_{\ell ,s}/4\pi R_{\mathrm{S}}^{2\ell +1}={\mathrm{\Phi }}_{\ell ,s}(\overline{y})-\frac{1}{2}\eta {\mathrm{\Phi }}_{\ell ,s}^{\prime }(\overline{y})$ with $\overline{y}=-\frac{1}{2}{\eta }^2\tau$ and $\eta =i\omega R_{\mathrm{S}}$. Here ${\mathrm{\Phi }}_{\ell ,s}$ is simply the leading-log solution to the renormalization group equation, but lifting the running logarithm to $\tau =\log (R_{\mathrm{S}}/R)-2{\sum }_{k\ge 2}{\zeta }_k{\eta }^{k-1}$ resums it to all orders. This tower of Riemann $\zeta$ values is the Newtonian phase in disguise: it originates from the long-range $1/r$ potential in the far zone, and is universal across multipole and spin. Our result exhibits a factorization pinned to three ingredients: the strength of horizon absorption, the running rate in the near zone, and the dressed logarithm in the far zone. Using shell effective field theory, we independently verify our formula for scalar, electromagnetic, and gravitational perturbations, reaching $\mathcal{O}(G^{15})$.

Observed massive neutron stars may contain heavier baryons such as $\mathrm{\Delta }$ isobars and hyperons in their interiors. In the presence of $\mathrm{\Delta }$ isobars, the neutrino emitting nucleonic Urca processes can be accompanied by $\mathrm{\Delta }$-direct-Urca processes involving nucleons and hyperons. Over the past three decades, significant theoretical effort has been dedicated to understanding the thermal evolution of neutron stars with the nucleonic and hyperonic Urca processes emerging as dominant cooling mechanisms. While recent studies have proposed the presence of $\mathrm{\Delta }$ isobars in the dense core of neutron stars, the specific contribution of the $\mathrm{\Delta }$-direct-Urca process to neutrino emissivity has not been explicitly quantified. In this Letter, we address this gap by deriving the neutrino emissivity associated with $\mathrm{\Delta }$-direct-Urca processes in dense matter inside neutron stars. We show that once $\mathrm{\Delta }$-direct-Urca processes become kinematically allowed, their emissivities are comparable to those of nucleonic-direct-Urca processes.

We uncover surprising hidden simplicity in Mellin amplitudes for tree-level anti–de Sitter (AdS) holographic correlators for AdS “gluon” (spin-1) operators. We define Mellin amplitudes with $n$ spinning operators via the so-called scaffolding of $2n$-scalar ones with specific projection operators for each spin state, which are rational functions of Mellin variables of $2n$ scalars generalizing flat-space scaffolding amplitudes. We classify possible three-point structures with spin 1, which take the same form as massive three-point amplitudes in flat space, and match them with special solutions such as those extracted from 6-scalar ones in ${\mathrm{AdS}}_5\times S^3$. Focusing on ${\mathrm{AdS}}_5$ gluons, we directly bootstrap spinning amplitudes in scaffolding form up to $n=6$ gluons (which amounts to $2n=12$ scalars) using factorizations, multilinearity, and flat-space limit. The results take a remarkably simple form in analogy with flat-space amplitudes, which can be constructed from familiar 3- and 4-vertices as well as propagators of massive spin-1 particles. Surprisingly, we find that vertices with any descendant levels are proportional to the primary ones with nice combinatorial coefficients, which makes manifest the correct flat-space limit in the simplest possible way.

We introduce a family of polytopes—in-in zonotopes—whose boundary structure organizes the contributions to scalar equal-time correlators in flat space computed via the in-in formalism. We provide explicit Minkowski sum and facet descriptions of these polytopes, and show that their boundaries factorize into products of graphical zonotopes and lower-dimensional in-in zonotopes, thereby mimicking the factorization structure of the correlators themselves. Evaluating their canonical forms at the origin—equivalently, calculating the volume of the dual polytope—reproduces the correlator. Finally, in a simple example, we show that the wave function decomposition of the correlator corresponds to a subdivision of the dual polytope.

The proton’s unpolarized $u(x)-d(x)$ parton distribution function (PDF) has been studied by a number of lattice QCD groups through large momentum expansion. However, due to lattice artifacts (excited state contaminations, unphysical pion masses, and discretization effects) and less-advanced theoretical analysis (renormalizations, large-distance extrapolations, and large-log resummations), the resulting PDFs cannot be compared strictly with experimental data. By using the state-of-the-art theoretical tools and mitigating the lattice artifacts empirically, we reanalyze the available datasets in the literature and find that the new PDF for the physical-limit-extrapolated dataset (MSULat20) is consistent with global fits within $\sim 1\sigma$, while others are broadly compatible. This provides evidence that large momentum expansion is capable of accurately predicting the $x$ dependence of the PDFs when ideal lattice data become available.

We study particle correlations in high energy jets by comparing the measured energy-energy correlator with that constructed from two individual energy flows with respect to the jet axis. This comparison demonstrates that the genuine correlations are stronger at moderate or large angles across all jet energies, indicating that they are coming from correlated splitting. Meanwhile, at small angles, they increase with jet energy, exhibiting a peculiar pattern that can be used to explore jet energy loss in heavy-ion collisions. This method will provide a unique tool to disentangle different physics by comparing the genuine correlations in jet energy-energy correlators between heavy-ion collisions and proton-proton collisions.

We describe a method for obtaining the scattering matrix for nuclear or chemical reactions on a finite lattice. Aside from the preparation of the initial and final states as wave packets, the only other operation required is unitary time evolution, making this approach ideal for simulations on quantum hardware. The central quantity is a time-dependent overlap between incoming and outgoing wave packets whose Fourier transform corresponds to the scattering matrix at fixed energy, from which one can calculate elastic and inelastic cross sections for reactions involving two interacting clusters. Working in Cartesian coordinates enables an efficient encoding of the problem on quantum hardware via the first quantization mapping, with favorable qubit scaling for describing asymptotic scattering states. Within this framework, we describe a quantum algorithm for probing the scattering amplitude through different angles, including the forward direction, which provides access to the total cross section via the optical theorem. We demonstrate our methods through a series of numerical examples, for both elastic and inelastic processes, comparing against exact calculations. The techniques we describe can more readily be extended to a large number of constituent particles than other existing approaches, once fault-tolerant quantum hardware becomes available.

The ${}^{16}\mathrm{O}:{}^{17}\mathrm{O}$ isotopic ratio is a widely used tracer of nucleosynthesis and mixing processes in red giant stars. Its value depends on the rates of the proton-capture reactions responsible for the production and destruction of ${}^{16}\mathrm{O}$ and ${}^{17}\mathrm{O}$ among which the ${}^{16}\mathrm{O}(\mathrm{p},\gamma ){}^{17}\mathrm{F}$ reaction plays a central role, as it involves both isotopes. This work reports on a new measurement of the ${}^{16}\mathrm{O}(\mathrm{p},\gamma ){}^{17}\mathrm{F}$ cross section carried out at the Laboratory for Underground Nuclear Astrophysics (LUNA) over a center-of-mass energy range of 200–380 keV, a region previously unexplored by experimental studies. Two complementary techniques were employed: prompt gamma-ray detection and activation. The results obtained with the two techniques are consistent within experimental uncertainties. From the measured cross sections and existing literature data, we evaluate a new thermonuclear reaction rate, which is then used to demonstrate how simultaneous measurements of stellar carbon and oxygen isotopic ratios constrain the initial mass and the extent of the mixing events in red giant branch stars. In particular, we demonstrate how the ${}^{12}\mathrm{C}$:${}^{13}\mathrm{C}$ abundance ratio is primarily sensitive to the temperature ${\mathrm{T}}_{\max }$ attained during mixing, whereas the ${}^{16}\mathrm{O}$:${}^{17}\mathrm{O}$ abundance ratio is highly sensitive to the initial stellar mass ${\mathrm{M}}_i$. Therefore, simultaneous measurements of these isotopic ratios can disentangle and place stringent constraints on ${\mathrm{M}}_i$ and ${\mathrm{T}}_{\max }$, and the remaining uncertainty is now dominated by stellar abundance measurements rather than nuclear-physics inputs.

Optically active spin defects are foundational for quantum technologies, yet common approximations underestimate their internal conversion (IC) rates by orders of magnitude. We propose a broad, predictive framework to compute IC rates that incorporates multiconfigurational effects via many-body wave functions in time-dependent density functional theory (TDDFT) and includes all-phonon-mode contributions via analytical nonadiabatic couplings. Our approach resolves discrepancies with experiment, achieving quantitative agreement for the ${\mathrm{NV}}^{-}$ center in diamond and identifying a previously overlooked nonradiative channel in the divacancy triplet lifetime in SiC.

In the context of waves in space-time modulated materials, we ask two questions: (1) how much energy does it cost to break time reversal symmetry ($T$-symmetry) and transition to a $PT$-symmetric state? and (2) can a $PT$-symmetric system have a “ground state” in the sense that no photons are present? Our model system is a periodic metamaterial set in virtual motion with velocity $c_g$ to become a space-time crystal. We find that the expectation of energy content is always increased on breaking symmetry. At the same time breaking T-symmetry introduces photon pairs even when we start from a T-symmetric ground state empty of photons, except in certain pathological examples that we describe. For a range of velocities, $PT$ symmetry is broken so that energy must be continuously invested to preserve motion, creating a trail of photon pairs. Here, energy must be continuously invested to preserve motion. We make an analogy with acoustic radiation generated from breaking the sound barrier.

Exact unstable solutions of the Navier-Stokes equations are thought to underpin the dynamics of turbulence but are usually computed in minimal computational domains. Here, we extend this dynamical systems approach to spatially extended turbulent flows featuring multiple interacting “substructures” and show how new simple invariant solutions can be constructed by spatial tiling of exact solutions from small-box calculations. Candidate solutions are found via gradient-based optimization of a scalar loss function which targets autorecurrence in spatially localized regions of the flow. We first identify 25 relative periodic orbits (RPOs) which are combinations of high-dissipation, small-box solutions with laminar patches. We then show that vertically stacked combinations of pairs of distinct small-box RPOs can form robust guesses for dynamically relevant two-tori in the larger domain. Finally, we show how our optimization procedure can identify “turbulent” trajectories which locally shadow a small-box RPO for multiple periods in a subdomain. These small-box combinations are possible as the flow spends prolonged periods in a regime where it can be effectively considered to be a pair of weakly coupled small-box systems. The new large-scale states are the first examples of solutions featuring multiple interacting substructures and support the long-standing hypothesis that turbulence can be built up as a spatiotemporal tapestry of smaller domain solutions.

We report on the realization of a planar, quasiballistic Josephson junction array using a Au micron-sized single crystal. The system exhibits a nonlocal, multiterminal Josephson effect, where the supercurrent between any two superconducting leads is governed by the phase coherence across the entire crystal. Key evidence includes a nonmonotonic dependence of the critical current on junction length and magnetic interference patterns with periods corresponding to the shared normal-metal area. Nonlocal transport measurements further confirm that the supercurrent between two electrodes depends on the phase configuration of all the others. Our results, supported by a developed theoretical model, establish a platform for exploring complex superconducting phenomena in multiterminal ballistic systems.

Understanding the dramatic slowdown of dynamics in glass-forming liquids remains one of the central challenges in glass physics. Using extensive molecular dynamics simulations, we uncover a topological origin of this phenomenon. Vortices in the hopping displacement vector fields are identified as the fundamental carriers of structural relaxation, whose density exhibits a pronounced maximum near the mode-coupling critical temperature. This nonmonotonic behavior signals a crossover of relaxation mechanisms from locally cooperative relaxation mediated by compact vortex structures to long-range facilitation governed by extended vortex lines. The peaking and subsequent decline of vortex density are accompanied by a sequence of topological phase transitions, which play a central role in the super-Arrhenius slowdown upon approaching the glass transition. Our results reveal a topological mechanism underlying dynamic slowdown and establish a direct link between topological defects and glassy dynamics.