Biological Physics
A Clinical–Metabolic Approach to Determining Calcium Requirements: Interplay of the Glucose Axis, PTH–Vitamin D Signalling and Bone Mineral Density
Alex Velez Cruz, Oscar Dam and Jairo Rondon
Calcium homeostasis is maintained by an endocrine network comprising parathyroid hormone (PTH), calcitriol and calcitonin, which defends serum calcium at the expense of skeletal reserves. Serum calcium is therefore an unreliable indicator of nutritional calcium status, and empirical supplementation remains common. This narrative review proposes a clinical–metabolic approach to estimating individual calcium requirements that integrates bone mineral density (BMD), vitamin D status and the compensatory PTH response. We make three contributions. First, we present a sigmoidal phosphate–PTH model in which a glucose-dependent gain term ($\Delta k_{\mathrm{gluc}}$) captures the heightened parathyroid sensitivity associated with dysglycaemia, and we illustrate it with simulated values for healthy adults, women and individuals with gluco-osteoporosis. Second, we translate the model into a four-step decision
algorithm that frames the intake gap as a net balance of intestinal absorption, renal excretion and bone turnover. Third, we incorporate the osteocyte–osteoblast bioenergetic axis (sclerostin/Wnt signalling, GLUT1-mediated glucose uptake, aerobic glycolysis and osteocalcin–insulin crosstalk) to explain why calcium supplementation may be ineffective when cellular energy supply or insulin sensitivity is impaired. The framework aims to prevent secondary hyperparathyroidism, avoid over supplementation and preserve skeletal integrity. The model values are simulated and require prospective clinical validation.
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Mathematical Physics · Cross-listed from stat.ML
Latent Score-Based Bayesian Cramér-Rao Bound Estimation for High-Dimensional Imaging Systems
Evan Scope Crafts, Thomas Wynn, Seonyeong Park et al. (+2 more)
We propose a data-driven framework for estimating the
Bayesian Cramér-Rao bound (CRB) in high-dimensional imaging systems with complex, analytically intractable priors. Direct CRB computation is challenging in this setting due to the need to model the prior score and to form and invert the
Bayesian Fisher information
matrix in very high dimensions. To address these issues, we first reformulate the inverse problem in the latent space of a pre-trained variational autoencoder, thereby dramatically reducing the dimensionality of the bound estimation problem while preserving the spatial structure of the images. The
Bayesian CRB is formed in this latent space and mapped back to the native parameter space using a change-of-variables formula. Second, to learn the latent prior score, we introduce a new sliced score matching objective defined in a Bochner space endowed with an $H^1(\Omega)$ Sobolev norm in space. This "Bochner-space sliced score matching" objective is consistent with standard sliced score matching, but penalizes errors in the spatial gradients of the score, suppressing high-frequency artifacts that otherwise contaminate the resulting CRB estimates. We validate the approach on a stylized quantitative photoacoustic computed
tomography (qPACT) breast imaging problem with over one million unknown parameters, using a foundation-model autoencoder derived from Stable
Diffusion. The proposed method yields stable, artifact-free
Bayesian CRB estimates that reflect the highly non-Gaussian structure of the learned prior and reveal the substantial impact of the prior on the relative performance of competing qPACT design schemes.
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All authors Evan Scope Crafts, Thomas Wynn, Seonyeong Park, Mark Anastasio, Umberto Villa
High Energy Physics (Phenomenology)
Reinterpreting ATLAS Dijet and Supersymmetry Searches in A Baryon-Number-Violating Heavy Scalar Framework
Tianyi Yang, Denis Rathjens, Alfredo Gurrola et al. (+1 more)
A reinterpretation of ATLAS searches targeting $b$-tagged dijet resonances and monotop-alike signatures at a center-of-mass energy of 13 TeV is presented using $pp$ collision data corresponding to integrated luminosities of 139 $\mathrm{fb}^{-1}$. These searches are used to constrain a
baryon-number-violating new physics model that introduces two scalar mediators $X_{1}$ and $X_{2}$ to simultaneously address the
baryon asymmetry of the universe and the dark matter relic abundance. By exploiting heavy-
flavor signatures and allowing for jet-rich final states, this reinterpretation provides complementary sensitivity to the model relative to non-
flavor-tagged inclusive dijet searches and conventional monotop reinterpretations. Assuming the mediators decay either into a pair of down-type
quarks or into a top
quark and a dark matter candidate, we translate the experimental upper limits into the model's parameter space. 95% confidence level exclusion limits are derived in the $\lambda_1$-$\lambda_2$ coupling plane for
benchmark mediator masses of 1.5, 1.75, and 2.0 TeV. For all three
benchmark masses, the $b$-tagged dijet reinterpretation excludes $\lambda_1 > 0.45$, while the bottom-squark reinterpretation excludes the region with $\lambda_1 > 0.3$ and $\lambda_2 > 0.6$, within the respective validated parameter domains.
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All authors Tianyi Yang, Denis Rathjens, Alfredo Gurrola, Francesco Romeo
High Energy Physics (Theory)
Exact effective central charges for a family of 3d superconformal field theories
Griffen Adams
We
conjecture an exact formula for the effective central charge, ceff, of a family of three- dimensional superconformal field theories related to Chern-Simons theory on a three-
manifold by the 3d-3d correspondence. The formula determines ceff , which governs the growth of a protected sector of states in the conformal theory, in terms of the dimension of a particular space of modular forms. We confirm our approach by checking against known results computed through resurgent continuation.
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Quantum Physics
Benchmarking Ansatze for Pauli Correlation Encoding in the Maximum Independent Set Problem
Cian C. Reeves, Aaron C. Kemp, Richard Padbury et al. (+5 more)
The increasing complexity of 5G and emerging 6G wireless networks has intensified the need for scalable optimization techniques capable of addressing computationally challenging combinatorial problems. While
quantum optimization offers a promising alternative, current near-term
quantum hardware remains limited by
qubit availability, noise, and scalability constraints. Pauli Correlation Encoding (PCE) has emerged as a
qubit-efficient optimization framework that addresses these challenges through
polynomial variable compression. However, the impact of compression on representability and solution recovery remains poorly understood. In this work, we investigate the hypothesis that increasing compression ratios introduce representability constraints arising from algebraic closure relationships among encoded Pauli observables. Using Maximum Independent Set
benchmark problems, we evaluate multiple PCE ansatz designs and compression ratios. We find that ansatz selection is critical to both solution quality and feasibility, with two ansatz families consistently outperforming alternatives and achieving approximation ratios approaching 0.9. Furthermore, increasing
circuit repetitions provides limited benefit and can degrade performance. Most notably, reducing compression by increasing the number of available
qubits significantly improves raw solution quality, while post-processed performance remains comparatively stable. These findings suggest that representability effects play an important role in compressed PCE encodings and provide new insight into the relationship among compression, ansatz design, decoding, and solution quality in scalable
quantum optimization.
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All authors Cian C. Reeves, Aaron C. Kemp, Richard Padbury, Eva Lia Tarquini, Christoph Kloeffel, Vedangi Pathak, Hamed Mohammadbagherpoor, Vincent Beltrani
Cosmology and Nongalactic Astrophysics
Baryonic Imprints on DM Halos: characterizing the full concentration-mass probability distribution with CAMELS
Elisa J. Gao and Dhayaa Anbajagane
The
halo concentration, which represents the distribution of matter within a
halo, is a vital tool for modeling the matter distribution on scales ranging from megaparsecs to sub-kiloparsecs. While significant progress has been made on connecting the impact of astrophysics on the mean concentration as a function of
halo mass, the same connection to higher moments of the concentration distribution remains far less explored. We employ the IllustrisTNG runs in the CAMELS simulation suite to simultaneously quantify the astrophysics and cosmology dependence of the first four moments of the concentration-mass relation; the mean, the scatter, the skewness, and the kurtosis. We use normalizing flows to model the concentration distribution as a function of
halo mass,
redshift, and six cosmological/astrophysical parameters. We focus on the mass range $M_{\rm vir} \in [10^{11}, 10^{14.5}] M_{\odot}/h$, and the
redshift range $z \in [0, 1]$. All higher-order moments exhibit a mass-dependent sensitivity to both astrophysics and cosmology. The behavior in dark matter-only simulations follows the known effects of active mergers and of
tidal stripping in smaller
halos. Once
galaxy formation is included, the scatter shows non-monotonic behavior at the Milky Way (MW) mass-scale, and the amplitude of this behavior is strongly influenced by the
baryon fraction and
supernovae (SNe) feedback parameters. The skewness has a large sensitivity to the
baryon fraction as well and is mostly insensitive to the other parameters, while the kurtosis follows the behavior set by the skewness. Results for the ASTRID simulation suite show similar behavior as that of IllustrisTNG. The cosmology and astrophysics dependence of these higher-order moments impact analyses that are sensitive to the full distribution of the concentration-mass relation, particularly for
halos at/below the MW mass scale.
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Biological Physics
Dynamics of microvesicle formation driven by glycocalyx
Ke Xiao and Chen-Xu Wu
Microvesicles (MVs), a type of
cell-secreted extracellular vesicle (EV), are essential for various biological processes such as local and long-distance intercellular communication and the disposal of unwanted materials. Recent evidence suggests that overexpression of MUC1 glycoproteins facilitates MV formation on the
cell membrane, but the mechanism underlying this nonequilibrium process remains unknown. Here, the kinetics of glycocalyx-driven MV formation is studied in the framework of Onsager's variational principle. Using this deterministic theory, we first show that the process of MV formation is accelerated for the denser and thicker glycocalyx-grafted
cell membrane and can be improved by reducing the ionic strength or enhancing the degree of glycocalyx ionization. Intriguingly, we further discover that there exists an optimal glycocalyx coverage for the fastest formation of MVs. We then investigated the process of MV formation using a
stochastic approach. Our results suggest that the transition rate is not constant, leading to the prediction of a shorter formation time compared to the deterministic approach. These findings provide valuable insights into the regulation of membrane morphology and MV secretion by the glycocalyx, with implications for both understanding and modulating these processes.
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High Energy Astrophysical Phenomena
Polarimetry of Black Hole Spin and Axisymmetric Emission Geometry
Vadim Bernshteyn, Daniel C. M. Palumbo, Dominic Chang et al. (+1 more)
The Event Horizon
Telescope array has measured the average polarimetric spiral morphology of black hole
accretion disks using the so-called “$\beta_2$” coefficient. This measurement is dominated by the weakly lensed, direct ($n=0$, counting
photon half-orbits) image of the disk, providing insight into
magnetic field structure around the M87* black hole. The future space-based Black Hole Explorer mission is expected to extend these capabilities, allowing for $\beta_2$ measurement of the strongly lensed $n=1$ image. In this paper, we explore the constraints $\beta_2$ measurements would impose on spacetime and
plasma geometries using a semi-analytic conical emission model. We show that
magnetic field orientation with respect to the emission cone qualitatively changes the dependence of $\beta_2$ modes on model parameters. For cone-aligned
magnetic fields, we find that the leading-order theoretical prediction from equatorial emitters of $\beta_{2,\, n=0} \approx\beta_{2,\, n=1}^*$ is the dominant trend even in off-equatorial models. Specifically, we show $\arg(\beta_{2,\, n=0}\,\beta_{2,\, n=1}^*) \approx 4\chi$, where $\chi$ is the angle determining in-cone
magnetic field orientation. We also find that $\arg(\beta_{2,\, n=0}\beta_{2,\, n=1})$ minimizes the effect of
magnetic field geometry while preserving a dependence on
spin that may be used to measure
spin direction. We find that observations of the
photon ring's $\beta_2$ complement the constraint from direct image polarization, and can greatly constrain
magnetic field structure even with an unknown external rotation measure. We also find that black hole
spin and emission cone opening angle would not be tightly constrained by $\beta_2$ alone, unless strong priors are placed on the
magnetic field geometry.
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All authors Vadim Bernshteyn, Daniel C. M. Palumbo, Dominic Chang, Tintin Nguyen
Mathematical Physics
Branching Gaps, Coexistence, and Boundary Influence for the Ising Model on Spherically Symmetric Trees
Farrukh Mukhamedov and Otabek Khakimov
In this paper, we study the
ferromagnetic nearest-neighbor Ising model on rooted spherically symmetric trees with one or \(q\) children per vertex, according to a prescribed sequence of branching levels. Unbounded runs of one-child levels force uniqueness at every nonzero homogeneous field and every finite inverse temperature. We quantify this effect through the locations of sufficiently long nonbranching stretches. Conversely, uniqueness need not entail any uniform rate: for each prescribed vanishing sequence, we construct a density-one tree whose finite-volume boundary influence decays more slowly along a subsequence. The tree retains branching number \(q\), although its nonzero-field coexistence region disappears. For eventually bounded gaps, we prove an optimal uniform comparison with the periodic tree having the largest allowed gap and obtain an explicit interval of coexistence fields. Thus bounded gaps are equivalent, within this family, to coexistence at some finite temperature and nonzero field. For eventually periodic gaps, Gibbs uniqueness is equivalent to fixed-point uniqueness of the full-period return map. A negative Schwarzian derivative yields a complete classification: in the supercritical regime the map has three fixed points inside a closed coexistence interval, two at its endpoints, and one outside. The nonzero endpoints are automatically nondegenerate folds, with square-root splitting of the merging branches.
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Statistical Mechanics
An Absorbing State Model with an Emergent Ising Transition
Shen Ai, Dov Levine and Paul Chaikin
We study a dynamical model of repulsive needles with centers fixed on a square
lattice. Needles that overlap are active and receive a repulsive rotation $ \theta \in [0,\epsilon)$; needles with no overlap do not move. This model exhibits an absorbing state transition. Nematic order was observed for long needles. For a range of needle lengths and $\epsilon$, the system self-organizes into a state with checkerboard
symmetry. As $\epsilon$ is increased, this phase melts and becomes disordered. Remarkably, we find that this phase boundary exhibits critical exponents identical to those of the
equilibrium 2D Ising model.
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Applied Physics
A Novel Iterative-Fitting Approach for the Thermal Characterization of Thin Fibers
William Spirnock, Alison Hake, Dihui Wang et al. (+3 more)
The transient electrothermal technique (TET) is widely used to measure the thermal properties of thin fibers and films, but its accuracy declines when radiative heat losses are significant and surface emissivity is unknown. These conditions are difficult to avoid at the microscale, while conventional analyses either neglect them or rely on separate measurements that introduce sequential errors. We present a TET implementation that determines multiple thermal properties and effective surface emissivity from only two transient measurements. An analytical model incorporating thermal radiation and variable heat generation supports sensitivity-guided, multiparameter fitting. Two forms of the temperature solution yield thermal conductivity and diffusivity, and thermal conductivity and volumetric heat capacity, respectively. An iterative fitting procedure then recovers intrinsic properties corrected for environmental effects while reducing the required sample count and measurement time. Measurements of amorphous silicon dioxide (SiO2) optical fiber and Hi-Nicalon Type S silicon carbide (SiC) fiber agreed with literature values to within an average error of approximately 10% across all samples. Experimental and numerical uncertainty analyses quantify measurement variability and relate it to sample geometry. This method simultaneously resolves multiple intrinsic thermal properties, corrects radiative-loss errors, and provides quantitative guidance for sample geometry selection.
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All authors William Spirnock, Alison Hake, Dihui Wang, Timothy Sullivan, Dana He, Heng Ban
High Energy Physics (Theory)
Quantum covariant bit threads
Matthew Headrick, Sreeman Reddy Kasireddy and Andrew Rolph
Entanglement entropy plays a central role in holography. The
quantum extremal surface (QES) formula is the standard tool in settings where both dynamics and bulk
quantum corrections are important, such as in black hole evaporation. We derive and explore QES-equivalent prescriptions —
quantum covariant bit threads — that formulate
holographic entanglement entropy in terms of minimal or maximal bulk flows rather than extremal surfaces. Like classical covariant bit threads, our prescriptions come in two types: (typically) spacelike V-flows, and timelike U-flows. To account for bulk
quantum corrections, the flow lines can start and end at points in the bulk, with the distribution of endpoints controlled by bulk
entanglement entropies. In our bit thread
language, the QES is a
quantum bottleneck to the flow, with some threads passing through it (accounting for the area term in the generalized
entropy) and others jumping across it (accounting for the
entropy term). Our prescriptions provide a complementary perspective to the QES formula and offer new insights on important phenomena such as black hole evaporation, islands, and baby universes.
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Astrophysics of Galaxies
The differences in the Narrow Line Region of nearby QSOs 1 and QSOs 2: II - Signatures of kinetic feedback
Gabriel R. Hauschild-Roier, Thaisa Storchi-Bergmann, Rogério Riffel et al. (+2 more)
We compare the integrated kinematic properties of the Narrow-Line Region (NLR) of ~1500 type 1 and ~700 type 2 QSOs at 0.4 < z < 0.5 using emission-line profiles from SDSS-IV spectra. The NLR [OIII] 5007 and Hbeta emission lines are fitted using a two-component model comprising a narrow (v_n, sigma_n) and a broad component (v_b, sigma_b), while fainter lines are fitted with a single Gaussian component. Both QSO types exhibit similar median narrow-component velocities (v_n ~ 0) and velocity dispersions (sigma < 200 km s^-1), consistent with motion driven by the host
galaxy's gravitational potential. However, parameters associated with the broad, high-velocity gas component (v_b, v_05, v_10, v_[NeV], sigma_b, W80 and W90) differ: QSOs 1 display larger blueshifts and broader emission lines than QSOs 2. This suggests that these components trace Active
Galactic Nuclei (AGN)
outflows, that appear stronger in QSOs 1, leading to higher estimated mass-
outflow rates (\dot{M}_out) and kinetic powers (\dot{{E}_out). Rather than offering absolute determinations of \dot{M}_out and \dot{E}_out – which remain subject to physical uncertainties – this statistical study supports the higher NLR excitation found for QSOs 1 in Paper I, as an orientation effect: in QSOs 1, we observe gas closer to the AGN core, where velocities and velocity dispersions are intrinsically higher. Nevertheless, the trend of QSOs 2 exhibiting higher average [OIII] luminosities than QSOs 1 suggests an evolutionary contribution, where QSOs 2 represent an early obscured AGN phase followed by a blowout phase that reveals the central core as a QSO 1.
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All authors Gabriel R. Hauschild-Roier, Thaisa Storchi-Bergmann, Rogério Riffel, Vincenzo Mainieri, Lara Gatto
Mesoscale and Nanoscale Physics
Escaping the Composite Fermi Sea: An Incompressible State at Half Filling in Graphene's Lowest Landau Level
Domagoj Perkovic, Ziwei Wang and Steven Herbert Simon
Recent experiments in monolayer and trilayer
graphene have observed incompressible even-denominator fractional
quantum Hall states within narrow regions of parameter space associated with crossings of zeroth Landau levels. This is surprising because at half filling the Coulomb interaction in the zeroth Landau level is expected to favour a compressible composite
Fermi liquid. Here we provide the first quantitative energetic study of the candidate incompressible phases and of the microscopic mechanisms that can stabilise them near such Landau-level crossings. Using exact diagonalization and infinite density-
matrix renormalisation group, we first study ultra-short-range corrections to the Coulomb interaction arising from finite layer separation,
lattice-scale effects, and electron-
phonon coupling. We find that a sufficiently strong attractive short-range interaction drives the composite
Fermi liquid first into a weakly paired \(d\)-wave pseudospin-singlet state and subsequently into a strongly paired state. However, microscopic estimates of these short-range corrections are far too small to stabilise either incompressible phase. We then incorporate Landau-level mixing through screening within the random-phase approximation. Screening substantially reshapes the effective interaction, suppresses the weak-pairing regime, and strongly enhances the tendency toward strong pairing. For a realistic range of microscopic parameters, the strongly paired phase is stabilised over a substantial fraction of that range. Our results identify the interplay of Landau-level mixing and ultra-short-range interactions as a plausible microscopic mechanism for the experimentally observed incompressible states in monolayer and trilayer
graphene and point toward a strongly paired composite-
fermion phase as their candidate ground state.
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Quantum Physics
Magic Quantum Code Surgery
Kathleen Chang, Anasuya Lyons, Yuanjie Ren et al. (+5 more)
Non-Clifford operations required for universal
quantum computation can be implemented by measuring logical Clifford operators. We present a generalized framework to fault-tolerantly measure transversal Clifford logical operators in
quantum low-density parity check (QLDPC) codes. Our protocol takes any QLDPC code and deforms the code across additional ancillary
qubits such that a product of stabilizers measures the desired logical Clifford operator. We prove that the deformed, Clifford-stabilized code remains LDPC and that its distance is preserved up to a constant factor independent of the number of physical
qubits. We further prove that the Clifford measurement has a fault distance against data
qubit and measurement errors that grows linearly with the distance of the original code. We apply our methods to implement logical non-Clifford gates in algorithmically relevant subroutines and to prepare magic states in
quantum stabilizer codes.
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All authors Kathleen Chang, Anasuya Lyons, Yuanjie Ren, Harald Putterman, Nathanan Tantivasadakarn, Victor V. Albert, Benjamin J. Brown, Dominic J. Williamson
Atmospheric and Oceanic Physics
A Multivariable Approach to the Regional Calibration of the Galvez Davison Index across Mexico Climate Regimes
Mauricio López-Reyes, Carlos Calvo-Sancho, Angel Meulenert et al. (+5 more)
The Gálvez Davison Index (GDI) is a thermodynamic diagnostic designed to summarize convective favorability in the tropical regions, yet its transferability across complex terrain and heterogeneous hydroclimates remains uncertain. Here we assess the climatological behavior and precipitation relevance of the GDI over Mexico using ERA5 hourly fields and CHIRPS daily precipitation for 1981 to 2024. We characterize the seasonal cycle and spatial contrasts of GDI and evaluate its association with rainfall using grid point and regional Pearson and Spearman correlations between daily maximum GDI and daily precipitation. To introduce an independent convective proxy, we also quantify the relationship between hourly GDI and ERA5 outgoing longwave radiation (OLR). Event level discrimination skill is assessed with receiver operating characteristic (ROC) curves and area under the curve (AUC) across regions and months. While GDI precipitation correlations are moderate and region dependent, GDI OLR coupling is consistently stronger, partly because OLR approaches a lower bound once deep convection develops, supporting its use as an intermediate proxy between thermodynamic favorability and rainfall. However, GDI values are systematically lower over elevated terrain because of the pressure level formulation of the index, which should be considered when interpreting the GDI over mountainous regions. ROC results indicate skill above random chance in nearly all region month combinations, with AUC frequently exceeding 0.75 during the core convective season. Building on these diagnostics, we propose a regionally calibrated GDI convective regime scale for May to October, adapted from the original GDI framework but recalibrated for Mexico using event conditioned distributions defined from OLR and precipitation and quantified with bootstrap uncertainty.
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All authors Mauricio López-Reyes, Carlos Calvo-Sancho, Angel Meulenert, José Francisco León-Cruz, Jose Manuel Gálvez, Javier Díaz Fernandez, Juan Jesús González-Alemán, María Luisa Martín Pérez
Quantum Physics
Quantum Query Complexity and Span Programs from Pre-Geometry
Justin Roy Cox, Neil Epstein, Zhirui Hu et al. (+2 more)
Span programs provide a general method for designing
quantum query
algorithms, and for Boolean coordinate queries their optimum cost agrees with the general adversary bound. We develop a matroidal organization of this optimization that separates dependence data determined by the query problem from the dependence structure chosen by a span program. The resulting source matroid records query dependence, target determination, and separation data, while a program matroid records dependencies among the target and response-labeled input elements of a candidate program. When a query problem admits a source matroid, we use its structure to organize adversary upper and lower bounds. For separating binary query sets in this setting, the global matroid-span-program optimum equals $\mathrm{Adv}^{\pm}_{\mathcal Q}(f)$. For a fixed regular program matroid, projective uniqueness reduces optimization over real representations to positive element weights. We express positive and negative costs as weighted basis ratios and derive exact $1$-, $2$-, and $3$-sum reductions, giving a compositional evaluation of the fixed-weight objective along a Seymour decomposition. For pointed $R_{10}$ closure, exact certificates give $3.9087553<\mathrm{Adv}^{\pm}_{\mathcal Q_R}(f_R)<3.9301$. The natural $R_{10}$ program has optimized cost $5$, while another regular program has cost at most $\sqrt{87/5}$. Recursive self-composition yields a family on $N$ input bits with randomized query complexity $\Omega(N^{0.7324867\ldots})$, an explicit
quantum algorithm using $O(N^{0.6500178\ldots})$ queries, and $Q(F)=\Theta(N^\alpha)$ for $0.6204277\ldots<\alpha<0.6229063\ldots$.
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All authors Justin Roy Cox, Neil Epstein, Zhirui Hu, Michael Jarret, Thomas De Mastri
Cosmology and Nongalactic Astrophysics
Weak lensing, Big Magnification: Recovering hidden lensing information from galaxy positions
Alex Alarcon and Carles Sánchez
Galaxy clustering and weak gravitational
lensing are powerful cosmological probes, traditionally combined through
galaxy clustering and
galaxy-
galaxy lensing in a $2\times2$pt analysis. An alternative is the foreground-background clustering cross-correlation induced by
lensing magnification, but measurements have achieved lower signal-to-noise than shear-based
lensing. We show that, for deep photometric samples, cancellation between
galaxies with positive and negative magnification responses can suppress this signal. Using DES Year 6 photometry and Balrog synthetic-source injections, we explore high-
redshift ($z\simeq0.7$-$2.5$) samples split by the sign and amplitude of their magnification response. This separation reduces cancellation and can increase both signal-to-noise and cosmological constraining power. We call the combination of foreground clustering and foreground-background cross-correlations with response-selected background samples BigMag. Forecasts with DES-like simulated data vectors show that, for an optimistic sample configuration and sufficiently precise response calibration, BigMag can achieve constraining power comparable to traditional $2\times2$pt using
galaxy positions alone. The same samples also enhance inverse
galaxy-
galaxy lensing (IGGL), a position-shear correlation dominated by magnification when the position sample lies behind the shape sample. Combining BigMag and IGGL further self-calibrates the magnification responses and yields marginalized $S_8$ constraints comparable to traditional $3\times2$pt analyses, and tighter for the more precise calibration scenarios considered here. The framework also enables near-zero-response samples for traditional $3\times2$pt and
geometric lensing-ratio analyses. These results motivate further optimization and validation of
galaxy selections to realize magnification as a complementary cosmological probe. [Abrg.]
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Mathematical Physics
Quenched Growth of Normal Matrices and Harmonic Measure
Oleg Alekseev
The
eigenvalues of a large normal random
matrix form a two-dimensional Coulomb gas. At fixed weight, the spectral droplet grows with the
matrix rank, and its semiclassical density increment is harmonic measure. We freeze an $N$-
eigenvalue configuration and sample $M$ further
eigenvalues using the projection onto
polynomials of degree less than $N+M$ that vanish at the frozen points. Their conditional law is an exact
polynomial ensemble in the potential of the frozen charges. For a regular analytic droplet, we prove that the spatial distribution of the new
eigenvalues converges to harmonic measure on the old boundary when $M/\log N\to\infty$ and $M/N\to0$. This convergence holds conditionally on the frozen spectrum, outside a set of frozen configurations whose probability tends to zero. The
equilibrium process formed from orthogonal
polynomials of degrees $N,\ldots,N+M-1$ has the same limit. An exact finite-rank identity relates
polynomial moments of the conditional mean to fluctuations of the frozen spectrum, with a remainder from
polynomial modes of degree $N+M$ and above.
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Nuclear Theory
Emulation of coupled-channels scattering for strongly deformed nuclei
M. Catacora-Rios, Kyle Beyer, Jin Lei et al. (+1 more)
Nucleon scattering off strongly deformed
nuclei such as the actinides requires coupled-channels (CC) calculations in which several members of the ground-state rotational band are coupled explicitly, which makes
Bayesian uncertainty quantification of deformed global optical potentials costly. We reformulate the direct boundary matching method (DBMM) by imposing its outgoing-wave boundary condition through a generalized Bloch operator; the resulting Bloch-DBMM solver converges as fast as the modern R-
matrix method and extends to charged projectiles on targets with deformed charge distributions. On top of it we build a reduced-basis emulator, CCB-ROM, whose basis vectors span all channels of a $J^\pi$ block simultaneously, and generalize the coupled-channels empirical interpolation method to arbitrary non-affine deformed interactions. For $n,p+{}^{232}$Th inelastic scattering with the ground-state band coupled through the $8^+$ state, at 4 and 35 MeV, the Bloch-DBMM solver is benchmarked against Frescox, and the emulator replaces a 2700-dimensional system by one of dimension $N_b\le200$, with a cost of $\mathcal{O}(N_b^3)$ independent of the number of channels, reproducing the exact solver calculations for all five band members with speed-ups of over two orders of magnitude. CCB-ROM thus delivers differential cross sections, transmission coefficients and reaction cross sections from one calculation, at a cost compatible with
Bayesian calibration of deformed optical potentials for
neutrons and
protons alike, and extends naturally to closed channels and to compound-
nucleus reaction codes.
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All authors M. Catacora-Rios, Kyle Beyer, Jin Lei, Filomena Nunes
Accelerator Physics
Quarter-wave shift for an extra pass in an energy recovery linac
Julien Michaud and Alex Fomin
Energy Recovery Linacs (ERLs) are advanced particle accelerators that recover the kinetic energy of the beam after interaction, significantly improving efficiency. In this paper we discuss an alternative operation mode for multi-pass ERLs with an extra pass at top energy, allowing a doubled beam current at the expense of an increased energy spread. We explain the theoretical concept behind this approach, detailing how the phase shift enables an extra acceleration pass without requiring additional hardware. Preliminary simulations on a
lattice similar to the PERLE one explore the feasibility of this method. The results are discussed in the context of ERL performance optimization, and potential applications for future accelerator designs are explored.
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Atomic Physics
Electrical and optical dipole polarizabilities of two lowest triplet states of the beryllium atom
Tymoteusz Mrozek and Krzysztof Strasburger
High-accuracy static and dynamic polarizabilities of the $2^3P_u$ and $^{3}S_{g}$ states of the neutral beryllium atom are reported. The calculations employed explicitly correlated Gaussian (ECG) basis sets, and first-order wave functions were obtained by minimization of the Hylleraas functional. The final basis sets used for the response-property calculations contained c.a. 7000-8000 functions, depending on the polarizability component and the chosen
symmetry. The results cover frequencies from the static limit, \(\omega = 0\), up to the third resonance for the \(2^{3}P_{u}\) state and up to the second resonance for the \(3^{3}S_{g}\) state. To the best of our knowledge, these are the first calculations of dynamic and static polarizabilities for these excited states of the beryllium atom using explicitly correlated basis sets.
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Quantum Physics
Efficient Quantum Monte Carlo through Cluster Expansions
Jorge Sánchez-Segovia and Álvaro M. Alhambra
The sign problem remains a major obstacle to extending the success of Monte Carlo methods to generic
quantum many-body systems. A powerful alternative relies on cluster expansions, which provide convergent representations of free energies and related quantities, with applications ranging from tensor network contractions to
quantum dynamics and
circuits. Within their convergence regime, these expansions often yield deterministic
polynomial-time
algorithms. However, such methods require exhaustive enumeration of connected clusters, leading to a computational overhead of $(N\varepsilon^{-1})^{\mathcal{O}(\log\Delta)}$, where $N$ is the system size, $\varepsilon$ the desired precision, and $\Delta$ the interaction-graph degree. This becomes particularly severe in long-range systems, where $\Delta\equiv N$, resulting in quasi-
polynomial runtimes. Here, we introduce a Markov chain
algorithm that samples cluster expansions directly in the space of connected clusters, replacing deterministic enumeration by Monte Carlo sampling. Because sampling occurs in an abstract cluster space rather than a physical configuration space, the conventional exponential sign problem is absent within the convergence regime. For general
polymer models, we establish an FPRAS with runtime $\tilde{\mathcal{O}}(N^4\varepsilon^{-3})$. For
quantum partition functions at temperatures $\beta\leq\beta_{\mathrm{sampling}}\equiv\mathcal{O}(1)$, this improves to $\tilde{\mathcal{O}}(N^{3+1/D}\varepsilon^{-3})$, where $D$ is the
lattice dimension. The framework directly applies to long-range
quantum systems with interactions $\propto1/r^\alpha$, including $2$-local models with $\alpha>2D$.
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Mesoscale and Nanoscale Physics
Integrating spin glass dynamics into nanomechanical resonators
S.Y. Grebenchuk, T.M. Savilov, Y.W. Ho et al. (+15 more)
Spin glasses are non-
equilibrium magnetic systems with pronounced slow relaxation, ageing, and chaotic, synaptic-like properties, whose unique history-dependent dynamics have remained difficult to harness in functional devices. Two-dimensional van der Waals
spin-glass magnets offer a route to overcome this limitation by allowing controlled coupling between
magnetic and mechanical degrees of freedom. Here, we demonstrate the integration of a
spin-glass functionality in nanoelectromechanical systems (NEMS) using thin exfoliated NbFeTe$_2$ films, which establishes a robust
spin-glass state down to a few tens of nanometer-thick layers. Using cryogenic
magnetic force microscopy, we reveal characteristic slow, hour-scale macroscopic
magnetic relaxation, associated with glassy reorganisation of its
magnetic domain clusters. Incorporation of thin NbFeTe$_2$ into membrane resonators allows the transduction of this glassy
magnetic domain relaxation into strain, shifting their mechanical resonance frequency. This provides a functional nanomechanical readout of
spin-glass dynamics and establishes a versatile platform for integrating frustrated magnetism into NEMS.
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All authors S.Y. Grebenchuk, T.M. Savilov, Y.W. Ho, A.K. Grebenko, M. Kravtsov, J.M. Wolf, D.A. Litvinov, Z. Yang, P. Cai, S. Ramachandran, R. Duan, L. Zheng, B. Özyilmaz, G. Eda, E.J.G. Santos, M. Koperski, K.S. Novoselov, M. Šiškins
Quantum Physics
Quantum-Assisted Optimization Guided by Machine-Learned Risk Maps for Aerial Surveillance Routing
Dorian Lauwerier, Alexis Vieloszynski, Yves Bérubé-Lauzière et al. (+1 more)
Analog
quantum computing with neutral atom computers is rapidly evolving into a promising way to perform combinatorial optimization tasks at scale. As technology matures, exploring real use cases leveraging such unique information processors becomes warranted; one example is logistics management where vehicles are assigned routes to perform a given task. Autonomous aerial vehicles (drones) are increasingly used for surveillance over a given territory. In this paper, we propose an innovative framework integrating classical machine learning forecasts and
quantum annealing to find the best combination of tours for a given surveillance criterion. The risk maps produced by machine learning are used to find possible surveillance tours, while a
quantum-assisted heuristic chooses the best combination, producing a full surveillance plan. By modelling our decision problem for drone paths as a Team Orienteering Problem (TOP) with additional constraints, we construct a new heuristic using
quantum annealing to find good solutions. We apply this framework to wildfire prevention, where finding tours most likely to detect a starting fire has clear benefits. We study the effect of larger
quantum resources on heuristic performance and compare those results to the use of classical resources.
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All authors Dorian Lauwerier, Alexis Vieloszynski, Yves Bérubé-Lauzière, Victor Drouin-Touchette
Quantum Physics
Exact Temporal Criticalities of Entanglement and Negativity in Gaussian and Non-Gaussian Dissipative Kitaev Chains
Shrey Chowdhary, Sanket Chirame, Stephan Haas et al. (+1 more)
When the two largest
eigenvalues of an
entanglement or negativity spectrum meet, the gap of the corresponding
entanglement or negativity
Hamiltonian closes while
entropies stay smooth, an event we call a temporal criticality. We ask when such criticalities occur in open fermionic systems, in which order, and whether they precede the
geometric decoherence time, at which the negativity starts to fall. We compare loss and gain, which respect
fermion parity only on average (weak
symmetry) and keep the state Gaussian, with density dephasing, which respects it in every jump (strong
symmetry) and makes the state non-Gaussian. We find that Gaussianity, rather than the
symmetry, fixes the criterion for a criticality. In a Gaussian state the
entanglement gap of a subsystem closes exactly when its two parity sectors carry equal weight, and the negativity gap closes exactly when this happens for the subsystem or its complement, so the negativity criticality never comes after the
entanglement one. Uniform balanced loss and gain only shrink the two parities and leave both criticalities in place at every rate, for any quadratic
Hamiltonian. In an open Kitaev chain, weak imbalanced loss and gain shift the criticalities by amounts set by the occupations at the cut, and at strong rates they allow a closing near the relaxation time only when an odd number of neighboring sites pass half filling. For dephasing we solve the non-Gaussian dynamics exactly at the point where the bond terms of the chain commute. Weak dephasing delays both criticalities and, away from the chain ends, moves them ahead of the parity balance, where the parity rules of Gaussian states would place them. As the dephasing rate approaches critical damping, both criticalities recede to infinite time, and at strong dephasing the negativity starts to fall long before either gap begins to shrink.
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All authors Shrey Chowdhary, Sanket Chirame, Stephan Haas, Rishabh Jha
High Energy Astrophysical Phenomena
Blasts from the Past: UHECR Excesses from a Population of GRB 21009A-like Transients
Nestor Mirabal
The most prominent feature in the ultra-high-energy
cosmic ray (UHECR) sky is a significant excess of events from the vicinity of Centaurus A (Cen A). In this paper we investigate whether the excess may be caused by a past GRB 221009A-like event rather than Cen A itself. If an extraordinary gamma-ray burst (GRB) went off in one of the
dwarf galaxies within the Cen A/M83 group, intergalactic
magnetic deflections would naturally spread out and delay its
cosmic ray signal, making it visible for $\sim 2\times 10^{5}$ years. Scaling this up, we model a local population of these exceptionally bright, narrow-jet transients within the \text{Greisen–Zatsepin–Kuzmin} (GZK) horizon. For a local volumetric rate of $\dot n_0\simeq4\times10^{-8}\ {\rm Mpc^{-3}\,yr^{-1}}$ and a jet half-opening angle of $0.8^\circ$, we estimate $\simeq3-7$ UHECR excesses across the sky at any given time. Varying the jet opening angle, GZK volume, and visibility time results in a broader range of excess values. It is possible to test this hypothesis by comparing the population predictions against existing and upcoming UHECR anisotropy data obtained by the Pierre Auger Observatory and the
Telescope Array.
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Quantum Physics
Robustness of Quantum Signal Processing and Resource-aware Polynomial Design
Thiago O. Maciel, Giancarlo Camilo, Allan Tosta et al. (+3 more)
Quantum signal processing (QSP) realizes operator functions through
polynomial transformations of a finite degree. In addition to function approximation errors, realistic implementations incur algorithmic errors also when encoding the input operator and in synthesizing gates into a discrete fault-tolerant gate set. We provide an end-to-end analysis of these errors and show that the input error propagation is governed by the operator-Lipschitz constant $L_\star$ of the implemented function. We then derive an efficient classical
algorithm to compute tight lower and upper bounds on $L_\star$, and we show that these bounds induce in turn lower and upper bounds on the total
quantum-resource cost (for instance, $T$-gate count) needed for QSP implementations compatible with a target total error. We further devise a procedure to search for a
polynomial with minimum cost based solely on its coefficients, yielding a resource-aware
polynomial-design procedure for QSP. We illustrate the resulting method for ground state energy estimation via
eigenvalue thresholding for the H$_6$ molecular
Hamiltonian. In the tested hardware profiles, the resource-aware family improves the total-error budget and reduces the modeled $T$-gate count by $51.9\%$–$56.7\%$ relative to the standard analytical
polynomial obtained from an error-function approximation.
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All authors Thiago O. Maciel, Giancarlo Camilo, Allan Tosta, Daniel Stilck-França, Leandro Aolita, Thais de Lima Silva
Strongly Correlated Electrons
The ALPS project release 3.0: open source software for strongly correlated systems
F. Alet, T. Chen, A. Feiguin et al. (+16 more)
We present release 3.0 of the ALPS (
Algorithms and Libraries for Physics Simulations) project, an open-source software project to develop libraries and application programs for the simulation of strongly correlated
quantum lattice models such as
quantum magnets,
lattice bosons, and strongly correlated
fermion systems. As in previous releases, development is centered on common data formats, on libraries to simplify and speed up code development, and on full-featured simulation programs that let non-experts carry out serial or parallel numerical simulations using the important
algorithms for
quantum lattice models: classical and
quantum Monte Carlo (QMC) using non-local updates, extended-ensemble simulations, exact and full diagonalization (ED), the density
matrix renormalization group (DMRG), and continuous-time QMC solvers for dynamical mean-field theory (DMFT). Major changes in release 3.0 include distribution of the pyalps binary through the Python Package Index (pip install pyalps) and through Spack for HPC systems; migration of development to GitHub with continuous integration and automated testing; relicensing of the package under the permissive MIT license; a rebuilt documentation and tutorial website, including a set of Jupyter-notebook tutorials and localized content; a broad modernization of the C++ codebase (C++17 compliance, Boost and NumPy 2.0 compatibility, and warning and dead-code cleanup) together with a major DMRG update and associated reliability and build-compatibility fixes; the removal of legacy components (the VisTrails provenance integration and the TEBD, MPS, and directed-worm-
algorithm application codes); archival of release 3.0.0 with a Zenodo DOI; and a formal governance and sustainability model developed under the US National Science Foundation (NSF) POSE program. The software is available at https://alps.comp-phys.org.
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All authors F. Alet, T. Chen, A. Feiguin, E. Gull, S. Iskakov, J. P. F. LeBlanc, F. Lin, A. Mirmira, G. Möller, L. Pollet, M. Rosales, V. W. Scarola, H. Shinaoka, H. Terletska, S. Todo, M. Troyer, M. Wallerberger, P. Werner, T. M. R. Wolf
Quantum Physics
On Information Propagation in Krylov Subspaces
Pablo Martinez-Azcona, Maximilian Meyer-Moelleringhof, Adolfo del Campo et al. (+1 more)
Krylov subspace methods provide an efficient tool for modeling any
quantum initial value problem as a one dimensional chain. A time ordered path formulation, in which the dynamical generator successively splits probability between paths, yields a speed limit within such dynamical subspaces. For power law growing Lanczos coefficients $b_n \sim n^\delta$ we find super ballistic lightcones, with an exponentially spreading lightcone for maximal growth $\delta = 1$. Causality in the Krylov chain constrains the Lanczos coefficients to grow at most linearly. We illustrate the validity of the above in the $SL(2, R)$ and Heisenberg Weyl
algebras, and in a many body skew field Ising model. Moreover, we extend the above bound to the family of $Q$ complexities. Lastly, mapping to a
spin chain gives a Lieb Robinson bound analogue and opens the problem to standard condensed matter methods.
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All authors Pablo Martinez-Azcona, Maximilian Meyer-Moelleringhof, Adolfo del Campo, Apollonas S. Matsoukas-Roubeas