Condensable algebras in 2+1d non-chiral topological orders characterize gapped boundary conditions and interfaces. Applied to the Symmetry Topological Field Theory, they allow classification of symmetric gapped phases and impose sharp constraints on possible phase transitions. A condensable algebra is specified not only by its underlying set of anyons, which end on the boundary or interface, but also by its algebra structure. We introduce the concept of twin condensable algebras, which have the same anyon decomposition, but inequivalent algebra structure. We revisit the classification of condensable algebras in $\mathcal{Z}(\text{Vec}_G^ω)$, i.e. in group-theoretical topological orders for finite groups $G$ with anomaly $ω$. In this context we are able to identify twin algebras that arise from different mechanisms, such as subgroup data, SPT cocycles, and symmetry actions. In particular, we construct infinite families of examples of twins from so-called Gassmann triples, and exhibit cases in which the reduced topological orders are inequivalent despite having identical anyon content. Physically, twin algebras describe distinct symmetric phases that have isomorphic spaces of ground states, but inequivalent order parameters. Such twin phases never exhibit relative spontaneous symmetry breaking, and can be used to construct phase transitions without hidden symmetry breaking, which are intrinsically beyond Landau transitions.

We introduce the concept of twin phases for a symmetry $\mathcal{S}$, defined as inequivalent phases, whose order parameters are part of the same generalized charge under $\mathcal{S}$. Stable, direct transitions between such twin phases are never spontaneous-symmetry-breaking transitions, even after (partially) gauging the initial symmetry $\mathcal{S}$: they are phase transitions without hidden symmetry breaking. We illustrate this with an (anomalous) finite group symmetry in 1+1d, which exhibits such intrinsically beyond Landau transitions.

We present a novel possibility that a network of domain walls bounded by cosmic strings generates a stochastic gravitational wave background (SWGB) signal originating from the spontaneous breaking of a gauged $U(1)_F$ flavor symmetry and the subsequent breaking of discrete $Z_2$ symmetry that accommodates dark matter. The gravitational wave (GW) spectrum produced by the string-bounded-wall network can be detected for high $U(1)_F$ breaking scales in forthcoming GW detectors including LISA, ET and SKA. The GW signal exhibits a distinctive frequency slope, in the infrared, compared to the standard cosmic-string case, in the frequency range between micro-hertz and hertz. We develop a possible strategy to distinguish and characterize GW spectrum of the hybrid defect from from other defects, such as stable cosmic strings, via employing the exact calculation with a machine-learning surrogate, based on a multilayer perceptron (MLP), trained on spectra obtained from the full numerical treatment. This is then used for rapid inference in the detector-specific signal-to-noise ratio (SNR) computation which also makes the process fast and efficient. We also discuss some possible complementarity between GW searches and Flavor observables in the laboratory.

Floquet engineering offers powerful tools to manipulate quantum states by periodically driving physical parameters. In this work, we investigate the quantum transport through two periodically driven impurities in a mesoscopic one-dimensional channel. By mapping the time-dependent Hamiltonian into an effective multichannel scattering problem, we unveil a rich landscape of transport phenomena arising from the interplay between Fabry-Perot cavity modes and Fano interference. We demonstrate that the inter-impurity distance acts as a critical control parameter, allowing for the formation of Bound States in the Continuum (BICs). Furthermore, we identify Quasi-BICs, extremely narrow resonances with finite lifetimes, that can be dynamically tuned by the drive amplitude. We show that these states enable a robust coherent trapping mechanism, allowing the system to switch from perfect transparency or reflection to strong localization with giant Wigner time delays. Our results suggest possible applications for tunable delay lines and quantum memories, with feasible experimental realizations in the context of cold atoms.

The crucial feature of resurgence theory is the ambiguity of non-perturbative behavior, reflected either in the different choices of integration contours or in the existence of several solutions to Ward identities. This is well illustrated by considering exactly solvable models, of which the prominent example is Chern-Simons theory. Its important chapter, which should have a direct generalization to arbitrary Yang-Mills, is the consideration of Wilson averages in the double-scaling limit of large representation and small coupling. For historical reasons, we call it a Kashaev limit. It possesses a natural interpretation in terms of quasiclassical/WKB approximation, which is, however, somewhat peculiar and thus sheds new light on the old story. The crucial point is the appearance of Alexander polynomials $Δ$ in two seemingly opposite roles: the classical $A$-polynomials have common roots with $Δ$, while Jones polynomials tend to $Δ^{-1}$ in the perturbative expansion. The consistency is provided by the peculiar form of the quantum $A$-polynomial, and the resolution of the puzzle is the co-existence of two different branches (phases) in the quasiclassical limit -- with non-trivial and with vanishing classical actions. The first leads to classical $A$-polynomials and hyperbolic volumes, the second -- to inverse Alexanders.

We study the global evolution problem for the Einstein equations under T2 symmetry on T3, allowing vacuum, scalar-field, and compressible-fluid matter models, governed by a general equation of state including isothermal and polytropic fluids. Under this symmetry, we obtain the first non-perturbative, global existence and stability theory with connection coefficients being merely square-integrable, which allows both impulsive gravitational waves and shock waves. In areal gauge, we introduce new fluid and geometric variables and reformulate the Einstein-Euler system as a first-order system of nonlinear balance laws with constraints and an entropy structure. The resulting formulation exhibits hyperbolicity, null forms, entropy currents, div-curl structure, maximum principles, and spacetime estimates. This leads to a notion of tame Einstein-Euler flow for which the essential geometric and fluid variables are square-integrable (finite energy), and the secondary variables are absolutely continuous (or, more generally, of bounded variation). In this non-perturbative and weak regularity setting, the equations remain meaningful even when the Weyl curvature concentrates into Dirac masses along timelike hypersurfaces, and the Ricci curvature remains only integrable. Our main results are a global existence theorem for areal foliations, a nonlinear stability theorem for well-prepared initial data, and a nonlinear instability theorem for geometrically oscillatory data, the latter producing measure corrections to the stress energy tensor. In the future-contracting regime, the areal foliation reaches a geometric singularity where the volume of T3 spatial slices degenerates to zero. The areal function reaches zero generically in the non-vacuum Gowdy-symmetric and vacuum torus-symmetric cases. In the future-expanding regime, the areal foliation is complete.

Strongly correlated electrons can be treated with a configuration interaction of Slater determinants grouped by number of unpaired electrons with exponential cost. The first two papers in this series demonstrated that single reference methods built from Richardson-Gaudin states gave results of similar quality at polynomial cost. In this contribution, the states are simplified substantially yielding the perfect-pairing state as a reference along with its low-lying excitations. The states are much simpler, the computational cost is substantially reduced, and there is no sacrifice in numerical accuracy. Second-order Epstein-Nesbet perturbative corrections for the valence electrons are similar in quality to the complete active space self-consistent field.

We propose an RG-improved effective-field-theory framework for the deeply bound dibaryon $d^*(2380)$, a $ΔΔ$ bound state in the $(J,I)=(3,0)$ ${}^7S_3$ channel. Its binding momentum $γ\simeq 320$ MeV gives $γ/m_π\simeq 2.3$, indicating the need to re-organize the short-range dynamics beyond a formal pionless EFT. We match the large-$N_c$-constrained pionless contact potential to a meson-exchange-saturated contact interaction in which the $σ,ρ,ω$ dynamics are integrated out at the hadronic scale $m_V$, yielding the controlled expansion parameter $γ/m_V\simeq 0.42$. Normalizing the contact coupling to the deuteron and substituting the phenomenological CD-Bonn couplings gives $B_{ΔΔ}\simeq 96$ MeV. The $\simeq 14\%$ discrepancy from $B_{\rm exp}=84$ MeV is of the natural size of $\mathcal{O}(1/N_c^2)\simeq 11\%$ corrections to the $NN$ potential, confirming compatibility with a controlled EFT expansion organized around the finite-range hadronic scale. As a result, the observed $d^*(2380)$ pole emerges from the virtual state to bound state by using the EFT re-organization in this work.

The fully self-consistent $GW$ (sc$GW$) approximation provides a Green's-function approach that is starting-point independent and offers a favorable cost-to-accuracy balance compared to high-level wavefunction methods. Here, we present an all-electron sc$GW$ study of uranium-containing diatomics (UC, UN, UO, and UF), incorporating relativistic effects through the exact two-component (X2C) formalism. We evaluate adiabatic ionization energies as well as electron-attachment and detachment energetics (AEA and VDE), together with equilibrium structures and harmonic vibrational frequencies, and we assess their sensitivity to basis-set choice and relativistic treatment. We find that sc$GW$ yields ionization energies and vibrational properties in very good agreement with experiment and high-accuracy theoretical estimates. For AEA and VDE, diffuse basis sets are essential for convergence. UF is a particularly challenging case for scalar relativistic methods because its electron-attachment and vertical detachment energies are strongly affected by spin--orbit coupling, highlighting the need for a variational two-component treatment. These results establish all-electron X2C-sc$GW$ as a practical route for accurate actinide-molecule energetics and spectroscopy and motivate future applications to larger uranium-containing systems.

Our purpose is to revisit the screw theory in light of the affine tensor formalism, introducing the co-momentum and momentum tensors. Our target-applications of the Euler-Poincaré equation are problems of mechanics such as the motion of the rigid body or the statics and the dynamics of Cosserat arches, in relation to the concept of momentum tensor. Using the framework of Ehresmann connections on the principal bundle of affine frames, we show that the Euler-Poincaré equation means that the momentum tensor is parallel-transported.

Gamma-ray bursts temporal profile can be extremely variable, going from a single pulse of a few seconds duration to multiple superimposed pulses occurring over tens or even hundreds of seconds. The variability displayed in the lightcurve of each gamma-ray burst can be the result of the activity taking place in the central engine that generates these violent phenomena, as well as due to magnetic reconnection activities at larger distances. The objective of this work is to find the shortest variability hidden in the lightcurves of the GRBs, with particular focus for the ones with measured redshift, on timescales as short as few milliseconds. This variability will then be related to physical characteristics of the central engine, and evidences of its relation with the spectral parameters of the burst, such as the isotropic energy and peak energy, will be presented. This research is even more relevant in view of the future generation of satellites with improved timing resolution, that will allow us to explore the possible variability in the microsecond region.

Repurposing natural gas pipelines for hydrogen transport requires understanding how external defects, like dents and gouges, affect structural integrity under H$_2$ exposure. To address this, we combine experiments with a new hydrogen embrittlement model aimed at large plastic straining scenarios, which integrates: (i) multi-trap hydrogen transport, (ii) finite-strain plasticity, and (iii) a hydrogen- and triaxiality-dependent damage law. Each constituent of the model is validated with experiments on X65 pipeline steel: (i) hydrogen permeation, (ii) full-scale pipe-indentation, and (iii) mechanical testing at different hydrogen and triaxiality levels. The validated model is used to study \textit{passive} (indent before H$_2$ exposure) and \textit{active} (indent with H$_2$) dents and gouges. Results reveal that hydrogen does not significantly increase the damage severity of those defects, unless hydrogen egress is completely precluded at the outer surface of a pipeline that is being pressurised internally and contains a pre-existing \textit{passive} dent with a gouge.

In this paper, we present an archival search for short gamma-ray bursts (sGRBs) over 13 years (2013-2025) of Fermi/GBM data using a Poisson matched-filter pipeline that performs a fully coherent analysis across all detectors and energy channels, significantly improving sensitivity relative to the onboard triggering algorithms. A central component of the analysis is the empirical estimation of trigger significance using 'timeslided' data, allowing each candidate to be assigned a probability of astrophysical origin. We also developed a new parameter-estimation framework based on the Poisson matched filter, which uses the global structure of the detected event across spectral, temporal, and spatial parameter spaces. This enables us to systematically classify bursts and distinguish between GRBs, soft gamma repeaters, terrestrial gamma-ray flashes, and solar flares. We identify 568 new GRB candidates with $p_{\text{astro}}\geq0.9$ and thousands of magnetar bursts, significantly expanding the known short-transient population in GBM data. To further strengthen the significance of the GRB candidates, we performed a targeted follow-up search in Swift/BAT rate data. Applying the followup to all of our triggers - including triggers below the detection threshold yielded 1736 temporally coincident events with association probability above $90\%$. The resulting probabilistically ranked catalog substantially expands the population of short GRBs and magnetar flares detected in GBM data and provides a statistically robust framework for multimessenger searches.

We present a general framework for the high-precision numerical evaluation of multivariate hypergeometric functions defined as solutions of holonomic systems of partial differential equations. Our approach adapts and extends methods originally developed for multi-loop Feynman integrals to the setting of hypergeometric functions of many variables. In particular, we construct Pfaffian systems for arbitrary multivariate hypergeometric functions by applying the Laporta reduction algorithm to suitable systems of differential relations. Next, we construct a numerical scheme based on the Frobenius method, which allows us to compute local power-series solutions with controlled precision and to transport them along prescribed paths in the space of variables. A central part of the paper is devoted to a systematic analysis of multivaluedness and branch structure: we show how the Frobenius method can be used to access different Riemann sheets in a controlled way and to track changes of the solution under analytic continuation around singular loci.

The Fundamental Plane (FP) of Early-Type Galaxies (ETGs) encapsulates a tight correlation among their structural and dynamical properties and provides an important benchmark for galaxy formation models. However, cosmological hydrodynamical simulations have historically struggled to reproduce the observed FP tilt, with discrepancies often attributed to to flawed feedback physics or insufficient resolution. Using the IllustrisTNG100-1 simulation, we show that adopting observationally motivated measurements, including Sérsic-derived photometric parameters and dynamically inferred velocity dispersions designed to minimise softening-length effects, substantially reduces the discrepancy between simulated and observed FPs. We further explore the impact of non-universal, mass-dependent Initial Mass Function (IMF) variations through forward modelling of their effects on galaxy structural and dynamical quantities. In particular, bottom-heavy IMF variations produce FP coefficients fully consistent with observational constraints for both direct and orthogonal fits. Our results suggest that a significant fraction of the long-standing FP tension arises from how galaxy observables are extracted and interpreted in simulations, although residual discrepancies may still reflect limitations in the underlying baryonic physics. These findings highlight the importance of observational realism and IMF variations for interpreting galaxy scaling relations and for improving the predictive power of hydrodynamical simulations of ETG formation.

Orbital transfers in multi-body systems are often studied as isolated trajectory design problems, making it difficult to identify the larger transport structure connecting families of periodic orbits, including which families act as hubs, gateways, relays, or persistently difficult-to-access regions. This work introduces a reachable-set-based framework for constructing orbital networks in the circular restricted three-body problem. Finite-$ΔV$ and finite-time-of-flight reachable-set overlaps are used to infer accessibility relationships between representative periodic orbit families on a common Jacobi energy manifold and to assemble these relationships into a weighted orbital network. Applied to the Earth-Moon system, the resulting network reveals distinct accessibility regimes in which direct reachability, graph connectedness, and feasible multileg closure emerge separately. The analysis identifies multi-orbiter cycler orbits as the dominant hub, gateway, and relay families, with the (3,2)-cycler dominating across much of the sampled budget plane and the short-period (1,1)-cycler dominating in the low-time-of-flight regime, while the stable 2:1 resonant orbit remains persistently difficult to access. Although the maximum-budget network is nearly complete in a binary sense, its weighted accessibility remains strongly non-uniform. Selected proxy-supported connections are refined into concrete trajectories through differential correction, with corrected transfer costs remaining below the proxy estimates in all tested cases. Together, the results demonstrate how reachable-set overlap geometry can expose large-scale transport structure in nonlinear gravitational systems without requiring exhaustive pairwise trajectory optimization.

We study the conditions for a three-phase contact line to return to a previous position. We drive a water-air-glass contact line between two horizontal plates, by slowly adding and removing water with a constant volume amplitude. For the first several cycles, the contact line ends each cycle with a different shape, in contrast with previously published work. Eventually the shapes begin to repeat, and the system has memory: a cycle with a smaller amplitude ends in a different shape, but even one cycle at the original amplitude recovers the steady-state shape. After a cycle at a larger amplitude, the steady-state shape is erased. We find that our tight control of the enclosed volume creates a global interaction, wherein only the least stable part of the contact line can move. Using theory and minimal models, we show that this interaction gives rise to the transient behaviors. Our study sheds light on the origins of reversibility and memory in a system where neither is guaranteed, and shows that the physics of contact line motion changes in a confined environment.

This note addresses a number of subtle issues pertaining to the long-standing problem of strong phonon-like fermion-boson coupling. Among the central topics are the customary Migdal-Eliashberg approximation in the pertinent Schwinger-Dyson gap equation and its solutions. The previously gained insight is assessed by contrasting it against the various (non-)supersymmetric variants of the Yukawa-Sachdev-Ye-Kitaev model. Also, some previously discussed (pseudo-)holographic aspects of fermion pairing in such models are commented upon.

Haldane pseudopotentials $V_{|m|}$ provide the effective interaction parameters governing correlated states in the fractional quantum Hall regime. In conventional formulations, these quantities are obtained by projecting the Coulomb interaction onto relative-angular-momentum states within the lowest Landau level, thereby neglecting virtual transitions to higher Landau levels. Here, we formulate a nonperturbative description of effective interactions directly from the exact two-electron spectrum in a magnetic field. By solving the relative-motion problem beyond the lowest-Landau-level approximation, we define renormalized pseudopotentials $V^*_{|m|}$ from the exact eigenenergies and introduce dynamical corrections $Δ_{|m|}=V^*_{|m|}-V_{|m|}$. The corrections remain systematically negative and depend strongly on both interaction strength and relative angular momentum, reflecting dynamical correlation effects associated with higher-state virtual admixture. The exact results reproduce the perturbative Landau-level-mixing limit at weak coupling while exhibiting substantial deviations in the strong-mixing regime, signaling the breakdown of low-order perturbative expansions. In particular, the short-range interaction channels relevant to Laughlin-type correlations undergo strong renormalization, leading to substantial modification of the effective interaction hierarchy in strongly interacting systems such as ZnO/MgZnO heterostructures. The present formulation establishes a microscopic framework for incorporating nonperturbative Landau-level-mixing effects into effective interaction theories of quantum Hall systems.

The polar-angle marginal of a centred bivariate Gaussian distribution, obtained after integrating out the radial coordinate, gives the two-dimensional angular central Gaussian (ACG) distribution of Tyler. While its trigonometric and vector-valued moments have been studied in detail, to our knowledge there are no explicit closed-form expressions for the \emph{linear} moments $\mathbf{E}[θ]$ and $\mathbf{E}[θ^{2}]$ on the natural domain $θ\in\left]-π/2,π/2\right[$. Here \textit{linear} refers to the ordinary moments $\intθ^{k}f(θ)\,dθ$ of the angle regarded as a real-valued variable, in contrast to the circular (trigonometric) moments $\mathbf{E}[e^{ikθ}]$ customary in directional statistics. We provide such expressions: the mean is a simple arctangent of the parameters, while the second moment is given by the real part of a dilogarithm. The derivation, based on a contour integration around the branch cut of $\arctan z$, is elementary. These quantities naturally arise in physics, where $θ$ is interpreted as a real-valued phase rather than a circular variable.

Constitutive laws for inelastic materials must satisfy strict thermodynamic admissibility requirements, yet current data-driven approaches sacrifice interpretability, even when formal guarantees are provided by physics-encoded architectures. We propose a symbolic regression framework for the data-driven discovery of dissipation potentials governing the evolution of internal variables within the Generalized Standard Materials (GSM) formalism. Starting from the Clausius--Duhem inequality, we enforce the thermodynamic requirements, convexity and non-negativity, that the dual dissipation potential must satisfy to guarantee non-negative mechanical dissipation. These requirements are formulated in the general subdifferential setting, encompassing rate-dependent (viscoelastic) and viscoplastic dissipative mechanisms, including potentials with genuine elastic domains, within a unified framework. Candidate potentials are generated by a composition-extended convexity-preserving grammar that guarantees thermodynamic admissibility \emph{by construction}. The framework is validated on synthetic datasets spanning Newtonian, power-law, and Bingham viscoplastic ground truths under process and measurement noise, and on experimental oscillatory shear measurements of a synthetic elastomer across multiple strain amplitudes and frequencies, where the discovered potentials reproduce the amplitude-dependent softening of the dynamic moduli and outperform a calibrated linear Zener baseline.

Direct real-space probes of altermagnetic order remain scarce. Here we introduce multiplet-selective photoelectron diffraction (PED), a methodology in which different regions of a transition-metal core-level multiplet act as distinct photoemission source waves. Using multiple-scattering calculations for the metallic altermagnet candidate CrSb, we show that selected Cr $3p$ multiplet features with predominantly $Y_1^{+1}$ and $Y_1^{-1}$ character generate robust diffraction asymmetries sensitive to altermagnetic domains. We demonstrate that both circularly and linearly polarized light provide access to the effect, while suitable combinations of domains, light polarizations, and multiplet-energy windows suppress nonmagnetic diffraction backgrounds. The proposed approach can be implemented using standard momentum-resolved photoemission instrumentation and establishes core-level PED as a practical route toward domain-resolved studies of altermagnets.

The two-particle correlation function measured in femtoscopic analyses provides access to the interaction potentials between emitted particles. This offers a unique opportunity to investigate interactions among charmed mesons and to explore the nature of possible exotic hadronic states. In this Letter, we study femtoscopic correlations of various charmed-meson pairs in relativistic heavy-ion collisions. The dynamical evolution of the system and charm hadron production are described within the Parton-Hadron-String Dynamics (PHSD) transport approach, while the correlation functions are computed using the Correlation Analysis Tool using the Schrödinger equation (CATS). We demonstrate that heavy-ion collisions provide a significantly more favorable environment than $pp$ collisions for accessing charmed meson femtoscopic correlations. This arises from enhanced charm-quark production, reduced relative momenta due to in-medium energy loss, and a strong suppression of initial-state correlations. Our results indicate that femtoscopic measurements in heavy-ion collisions offer a sensitive probe of charmed meson interactions and possible hadronic molecular states.

Device-independent (DI) quantum cryptography provides secure cryptography with minimal trust in, or characterisation of, the used quantum devices. An essential component of DI protocols is the use of randomness extractors for privacy amplification, but these typically require an initial seed of randomness that introduces a potential vulnerability. To solve this problem, the security of seedless extractors was proven in Quantum 9, 1654 (2025). The core idea was to use the Bell violation of the raw data, rather than its min-entropy, as the extractor promise. However, the large fluctuations in the Bell inequality used required many rounds to precisely estimate the Bell violation, consuming substantial randomness and making the protocol very inefficient. In this work, we present a new proof technique based on a truncation method that allows the user to estimate the protocol parameters with an asymptotically vanishing fraction of rounds and, as a consequence, achieves the optimal rate of one key bit per singlet. Notably, we prove this result using seedless extractors that can be implemented efficiently.

Exoplanet demographic studies rely on large and homogeneous catalogs, yet stellar multiplicity remains incompletely characterised in many planet samples. Misidentified stellar companions can bias both stellar and planetary parameters, leading to ambiguous and incomplete conclusions about planet formation and evolution. We aim to construct a robust and reliable reference catalog of S-type exoplanets for future investigations of planet formation and evolution in multiple-star environments, and to reassess exoplanet demographics by comparing planets hosted by single-stars and binary systems in a statistically consistent framework. We update the PlanetS catalog of transiting exoplanets by systematically identifying gravitationally bound stellar companions using Gaia DR3. Adopting a deliberately conservative classification, we distinguish binary and single-star systems and constructed a matched control sample of single hosts to mitigate selection and observational biases. Using this curated dataset of 860 transiting exoplanets including 133 S-type planets, we performed a comparative demographic analysis of planetary properties as a function of host multiplicity, stellar mass, and binary separation. We find a binary fraction of 19.4% relative to the control sample (15.5% relative to the full single-star sample), consistent with previous estimates but derived from a larger and more homogeneous dataset. Significant demographic differences emerge in the giant planet regime, less affected by observational biases. We find that giant planets in binaries tend to be more massive than their single-star counterparts and to orbit closer to their host stars, making their radius more inflated. In particular, we identify a tentative excess of giant planets orbiting M-dwarfs in binaries with separations < 1000 AU, suggesting a potentially informative regime for future demographic studies.

Entanglement is known to be a powerful resource that improves performance in various quantum information and computational tasks. A standard example of such a phenomenon is the possibility of perfectly discriminating all four Pauli operations in a single shot via the superdense coding protocol. While entanglement is often a powerful resource for quantum channel discrimination, this is not necessarily the case. In this work, we identify scenarios in which the maximally entangled state is a bad choice of input state and, more generally, show that excessive entanglement can reduce channel discriminability dramatically. To do so, we present an explicit pair of unitary channels which are perfectly discriminable without entanglement, but for which any strategy with maximally entangled input states is $ε$-close to a blind uniform guessing strategy. To develop a systematic approach, we introduce the concepts of Maximal Entanglement Worst Case (MEWC) and Maximal Entanglement Best Case (MEBC) pairs of channels, and present conditions for a pair of channels to be MEWC or MEBC. With these conditions, we show that the optimal input states for discriminating MEWC pairs of channels are necessarily separable, and provide non-trivial examples of measurement channels for which entanglement necessarily reduces the maximum probability of discrimination.

When considering the complexity of communication protocols, the aim is to perform a certain task with the minimum amount of communication resources, such as time and transmitted information. The use of quantum states may lead to an exponential advantage in the use of such resources. Here, we are interested in the task of calculating the Euclidean distance between two vectors representing real data sets. It has been previously shown that it is possible to obtain an advantage for this task based on quantum fingerprinting. This protocol is defined in the simultaneous message passing model of communication complexity, where the two parties do not communicate with each other but send data to a third party, and exploits practical fingerprints generated using trains of coherent state pulses instead of highly entangled qubit states that are hard to generate for large input sizes needed to demonstrate an exponential advantage. We perform a proof-of-principle experimental demonstration of the Euclidean distance protocol using amplitude modulation techniques for encoding non-binary data sets and high-performance superconducting nanowire single-photon detectors required to increase the accessible input size. We show a quantum advantage in transmitted information surpassing the best classical protocol for an input size of $10^8$, for diverse types of data sets, including those corresponding to real grayscale images, and with reasonable precision and error bounds. Our results highlight the potential of quantum communication complexity for use in a broad set of applications.

Recent experimental observations in the noncentrosymmetric Weyl semimetal PtBi$_2$ indicate unconventional superconductivity hosted by topological surface states -- Weyl Fermi arcs -- with a node at the center of each arc. Focusing on these Fermi arcs, we calculate the electronically mediated pairing interaction using a Kohn-Luttinger approach and find that, in a large region of the phase diagram, the leading superconducting instability has an $i$-wave symmetry featuring precisely such an intra-arc node. We study the dependence of the leading superconducting instabilities on electronic interaction parameters and chemical potential and show that the $i$-wave state is robust to changes in the model parameters. Our results provide a possible mechanism for the observation of topological $i$-wave superconductivity on the surface of PtBi$_2$ and may have implications for the broader landscape of superconducting instabilities arising from repulsive interactions on the surfaces of Weyl semimetals.

The targeted discovery of inorganic materials remains challenging due to the vastness of compositional design spaces and the high cost of exhaustive screening. Task-specific generative artificial intelligence represents a particularly efficient alternative to screening, yet demands tedious collection of training data before providing real benefit. General-purpose large language models (LLMs) have recently shown tremendous potential for the targeted generation of single, optimal materials compositions without the need for task-specific fine-tuning. However, it is unclear whether LLMs generally pose an advantage compared to specialized generative models, in particular in large design spaces. Here, we demonstrate that such models are capable of covering entire regions of the targeted property space effectively and systematically. Using Elpasolite materials as an established benchmark for generative tasks in large chemical spaces, we find that an iterative prompt-and-response framework is able to recover on average 96% of all low-energy Elpasolites in the target region. This performance, driven mainly by iterative in-context learning, surpasses the generative abilities of previous, task-specific models. Our results establish general-purpose LLMs as flexible and accessible components for inverse materials design workflows.

The distribution of entangled pairs of photons on the links composing a quantum network, combined with Bell state measurements and teleportation, is the basic apparatus to transfer quantum bits (qubits) over long distances. Entanglement distribution establishes an end-to-end entangled pair while consuming intermediate pairs on links and holding them for a certain time period. The technical literature identifies two main kinds of protocols, parallel and sequential ones, the latter having an advantage in resource consumption over the former. In this paper, we introduce an efficient swapping protocol called Progressive Swapping to the Middle (PSM) as it combines the existing Progressive Swapping (PS) protocol from both extremities of a path that meet in the middle where the received pairs are swapped. We compare PSM with two parallel protocols and PS; in our evaluation, we take into account imperfect memories and fidelity degradation. We demonstrate that PSM yields a much better link probability than PS while keeping a reasonable link fidelity, and shows an advantage in resource consumption over other protocols.