Flavor Nonsinglet Splitting Functions at Four Loops in QCD: Fermionic Contributions.

We have determined the fourth-order n_{f} contributions to the two splitting functions governing the evolution of all flavor differences of quark distributions of hadrons in perturbative quantum chromodynamics with n_{f} light flavors. The analytic forms of these functions are presented in both Mellin N space and momentum-fraction x space for a general gauge group. In the small-x limit double logarithms occur, but the small-x rise of both splitting functions is confined to extremely small-x values, x≲10^{-6}.

Unravelling the molecular network structure of biohybrid hydrogels.

Glycosaminoglycan-based biohybrid hydrogels represent a powerful class of cell-instructive materials with proven potential in tissue engineering and regenerative medicine. Their biomedical functionality relies on a nanoscale polymer network that standard microscopy techniques cannot resolve. Here, we introduce an advanced analytical approach that integrates transmission electron microscopy, X-ray scattering, and computer simulations to directly and quantitatively characterize the nanoscale molecular network structure of these hydrogels.

Friedel oscillations and chiral superconductivity in monolayer NbSe.

The nature of the dominant pairing mechanism in some two-dimensional transition metal dichalcogenides is still debated. Focusing on monolayer 1H-NbSe, we show that superconductivity can be induced by the Coulomb interaction when accounting for screening effects on the trigonal lattice with multiple orbitals. Using ab initio based tight-binding parametrizations for the relevant low-energy d-bands, we evaluate the screened interaction microscopically.

Brownian motion with stochastic energy renewals.

We investigate the impact of intermittent energy injections on a Brownian particle, modeled as stochastic renewals of its kinetic energy to a fixed value. Between renewals, the particle follows standard underdamped Langevin dynamics. For energy renewals occurring at a constant rate, we find non-Boltzmannian energy distributions that undergo a shape transition driven by the competition between the velocity relaxation timescale and the renewal timescale.

Topology and kinetic pathways of colloidosome assembly and disassembly.

Closed capsules, such as lipid vesicles, soap bubbles, and emulsion droplets, are ubiquitous throughout biology, engineered matter, and everyday life. Their creation and disintegration are defined by a singularity that separates a topologically distinct extended liquid film from a boundary-free closed shell. Such topology-changing processes are of fundamental interest.

Forged by charge: polaron-induced matrix formation in silicon nitride conversion-type anodes for lithium-ion batteries.

The quest for high-capacity anode materials is vital in developing future lithium-ion battery technologies. While silicon-based anodes offer high theoretical capacity, their commercial realization is hindered by instability associated with large volume changes. Amorphous silicon nitride (a-SiN) has emerged as a promising alternative, acting as a conversion-type anode where lithium incorporation drives the formation of a structurally robust matrix and active phases.

Fluid-derived lattices for unbiased modeling of bacterial colony growth.

Bacterial colonies can form a wide variety of shapes and structures based on ambient and internal conditions. To help understand the mechanisms that determine the structure of and the diversity within these colonies, various numerical modeling techniques have been applied. The most commonly used ones are continuum models, agent-based models, and lattice models.

Visualizing Three-Qubit Entanglement.

We present a graphical framework to represent entanglement in three-qubit states. The geometry associated with each and is analyzed, revealing distinct structural features. We explore the connection between this geometric perspective and the tangle, deriving bounds that depend on the entanglement class.

Sociohydrodynamics: Data-driven modeling of social behavior.

Living systems display complex behaviors driven by physical forces as well as decision-making. Hydrodynamic theories hold promise for simplified universal descriptions of socially generated collective behaviors. However, the construction of such theories is often divorced from the data they should describe.

Influence of vibrational motion and temperature on interatomic Coulombic electron capture.

Interatomic Coulombic electron capture (ICEC) is an environment-mediated process in which a free electron attaches to a species by transferring excess energy to a neighbor. While previous theoretical investigations assumed fixed nuclei, recent studies indicate that nuclear dynamics significantly influences the ICEC process. In this work, we incorporate the vibrational motion into an analytical model of the ICEC cross section, including both energy and electron transfer.

Universality of Rényi Entropy in Conformal Field Theory.

We use the thermal effective theory to prove that, for the vacuum state in any conformal field theory in d dimensions, the nth Rényi entropy S_{A}^{(n)} behaves as S_{A}^{(n)}=[f/(2πn)^{d-1}][Area(∂A)/(d-2)ε^{d-2}](1+O(n)) in the n→0 limit when the boundary of the entanglement domain A is spherical with the UV cutoff ε. The theory dependence is encapsulated in the cosmological constant f in the thermal effective action. Using this result, we estimate the density of states for large eigenvalues of the modular Hamiltonian for the domain A.

Chirally Protected State Manipulation by Tuning One-Dimensional Statistics.

Chiral symmetry is broken by typical interactions in lattice models, but the statistical interactions embodied in the anyon-Hubbard model are an exception. This is an example for a correlated hopping model where chiral symmetry protects a degenerate zero-energy subspace. Complementary to the traditional approach of anyon braiding in real space, we adiabatically evolve the statistical parameter and find nontrivial Berry phases and holonomies in this chiral subspace.

Spectral Constraints on Theories of Colored Particles and Gravity.

In this Letter, we consider effective field theories for light fields transforming under the fundamental or adjoint representation of a continuous group. Assuming tree-level completions, we demonstrate that, in the presence of gravity, crossing symmetry combined with twice-subtracted sum rules leads to constraints on the irreducible representations that the ultraviolet degrees of freedom must populate. A spectrum is allowed only if its low energy projection contains the graviton pole.

Observation and Control of Chiral Spin Frustration in BiYIG Thin Films.

Chiral interactions within magnetic layers stabilize the formation of noncollinear spin textures, which can be leveraged to design devices with tailored magnetization dynamics. Here, we introduce chiral spin frustration in which energetically degenerate magnetic states frustrate the Dzyaloshinskii-Moriya interaction. We demonstrate magnon-driven switching of the chirally frustrated spin states in Bi-substituted yttrium iron garnet thin films.

Does provable absence of barren plateaus imply classical simulability?

A large amount of effort has recently been put into understanding the barren plateau phenomenon. In this perspective article, we face the increasingly loud elephant in the room and ask a question that has been hinted at by many but not explicitly addressed: Can the structure that allows one to avoid barren plateaus also be leveraged to efficiently simulate the loss classically? We collect evidence-on a case-by-case basis-that many commonly used models whose loss landscapes avoid barren plateaus can also admit classical simulation, provided that one can collect some classical data from quantum devices during an initial data acquisition phase. This follows from the observation that barren plateaus result from a curse of dimensionality, and that current approaches for solving them end up encoding the problem into some small, classically simulable, subspaces.

Quantum metric-induced giant and reversible nonreciprocal transport phenomena in chiral loop-current phases of kagome metals.

Emergence of quantum orders with nontrivial quantum geometric properties in metals represent central issues in condensed matter physics. In this context, recently discovered chiral loop-current order in kagome metals has garnered significant attention. Particularly noteworthy is the giant electrical magnetochiral anisotropy (eMChA) observed in CsVSb, which provides compelling evidence for the simultaneous breaking of time-reversal and inversion symmetries.

Tunable anomalous Hall and Nernst effects in magnetic Weyl semimetalsCo2-xCrxMnGe.

The discovery of magnetic Weyl semimetals (WSMs) has drawn significant interest due to their exceptional topological properties and anomalous transport behaviors, presenting exciting possibilities for advanced technological applications. Co-based Heusler compounds, with their unique band structures, have emerged as key materials for exploring the interplay between magnetism and topology. In this work, we perform a detailed first-principles study on Co2-xCrMnGe Heusler alloys (0⩽⩽1), proposing new candidates with significantly enhanced nontrivial transport properties.

Quantifying the Influence of Poly(Ethylene glycol) on the Micelle Formation of Nonionic Detergents.

The influence of poly(ethylene glycol) (PEG with molecular weights between 400 and 4000) on the critical micelle concentration (CMC) of nonionic detergents with maltose as well as oligo(ethylene glycol) head groups is determined by using 8-anilinonaphthalene-1-sulfonate (ANS) as fluorescence probe. The CMC is found to increase with the concentration of PEG (0%-30% (w/v)) in a way that is determined by the molar concentration of oxyethylene (OE) units and independent of the molecular weight of the added polymer. The effect is explained with the extended conformation of PEG in aqueous solution allowing for an interaction of detergent monomers with individual OE units via their alkyl tails.

Massive extended streamers feed high-mass young stars.

Stars are born in a variety of environments that determine how they gather gas to achieve their final masses. It is generally believed that disks are ubiquitous around protostars as a result of angular momentum conservation and are natural places to grow planets. As such, they are proposed to be the last link in the inflow chain from the molecular cloud to the star.

Spin Liquid and Superconductivity Emerging from Steady States and Measurements.

We demonstrate that, starting with a simple fermion wave function, the steady mixed state of the evolution of a class of Lindbladians, and the ensemble created by strong local measurement of fermion density without postselection can be mapped to the "Gutzwiller projected" wave functions in the doubled Hilbert space-the representation of the density matrix through the Choi-Jamiołkowski isomorphism. A Gutzwiller projection is a broadly used approach of constructing spin liquid states. For example, if one starts with a gapless free Dirac fermion pure quantum state, the constructed mixed state corresponds to an algebraic spin liquid in the doubled Hilbert space.

Spatially Resolved Dynamics of the Amplitude Schmid-Higgs Mode in Disordered Superconductors.

We investigate the spatially resolved dynamics of the collective amplitude Schmid-Higgs (SH) mode in disordered s-wave superconductors and fermionic superfluids. By analyzing the analytic structure of the zero-temperature SH susceptibility in the complex frequency plane, we find that, when the coherence length greatly exceeds the mean free path, (i) the SH response at fixed wave vectors exhibits late-time oscillations decaying as 1/t^{2} with frequency 2Δ, where Δ is the superconducting gap; (ii) subdiffusive oscillations with a dynamical exponent z=4 emerge at late times and large distances; and (iii) spatial oscillations at a fixed frequency decay exponentially, with a period that diverges as the frequency approaches 2Δ from above. When the coherence length is comparable to the mean free path, additional exponentially decaying oscillations at fixed wave vectors appear with a frequency above 2Δ.

Direct Constraints on Strongly Interacting Dark Matter from the James Webb Space Telescope.

Direct-detection searches for dark matter are insensitive to dark matter particles that have large interactions with ordinary matter, which are stopped in the atmosphere or the Earth's crust before reaching terrestrial detectors. We use "dark" calibration images taken with the HgCdTe detectors in the near-infrared spectrograph (NIRSpec) on the James Webb Space Telescope (JWST) to derive novel constraints on sub-GeV dark matter candidates that scatter off electrons. We supplement the JWST analysis pipeline with additional masks to remove pixels with high-energy background events.

Introduction to correlation networks: Interdisciplinary approaches beyond thresholding.

Many empirical networks originate from correlational data, arising in domains as diverse as psychology, neuroscience, genomics, microbiology, finance, and climate science. Specialized algorithms and theory have been developed in different application domains for working with such networks, as well as in statistics, network science, and computer science, often with limited communication between practitioners in different fields. This leaves significant room for cross-pollination across disciplines.

An accurate and efficient framework for modelling the surface chemistry of ionic materials.

Quantum-mechanical simulations can offer atomic-level insights into chemical processes on surfaces that are crucial to advancing applications in heterogeneous catalysis, energy storage and greenhouse gas sequestration. Unfortunately, achieving the accuracy needed for reliable predictions has proven challenging. Density functional theory, widely used for its efficiency, can be inconsistent, necessitating accurate methods from correlated wavefunction theory.