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Tuesday 29 September

Mathematical Physics · Cross-listed from math.SP

The Dry Ten Martini Problem for subcritical Type I operators

We supply the details of the subcritical dry Ten Martini statement announced in [6, Remark 1.3]: for every irrational frequency, every subcritical Type I energy with resonant rotation number is an endpoint of an open spectral gap. The proof combines the all-frequency Puig argument developed there with quantitative almost reducibility. A different proof was recently given by Li [7].
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General Relativity and Quantum Cosmology

Oscillatory dark energy with phantom crossings in Einstein-Gauss-Bonnet gravity

Recent baryon acoustic oscillation measurements from the Dark Energy Spectroscopic Instrument (DESI), combined with supernova observations, show a mild preference for an evolving dark-energy equation of state, in which dark energy remains phantom-like at higher redshift while a transition toward the quintessence regime emerges around $z\lesssim0.5$. Beyond the monotonic evolution of the equation of state, an oscillatory dark-energy scenario provides a potential alternative realization of dynamical dark energy. We study such an oscillatory scenario within the Einstein-scalar-Gauss-Bonnet gravity framework, where a scalar field with a hybrid exponential-quadratic potential couples nonminimally to the Gauss-Bonnet (GB) invariant. We choose a Gaussian GB coupling function localized around the minimum of the potential. During the late-time epoch, the field thereby oscillates around the potential minimum and eventually exits toward a stable de Sitter attractor phase. In the minimally coupled limit, the effective equation of state oscillates in the quintessence regime at low redshift, $z\sim0$, without crossing the phantom divide. The nonminimal coupling amplifies the oscillations and drives the effective equation of state across the phantom divide multiple times. Although a sufficiently strong coupling can induce negative scalar and tensor sound speeds, rendering the perturbation modes unstable. We identify a region of parameter space in which the model undergoes multiple phantom crossings while remaining free of ghost and gradient instabilities and approaching a stable de Sitter attractor in the future.
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Statistical Mechanics

Phase separation, morphology, and metastability in the three-dimensional active Potts model

We study the three-dimensional active Potts model (APM) on a cubic lattice with 2, 4, and 6 orientational states. The steady-state phase diagrams exhibit low-density gaseous, high-density polar liquid, and liquid–gas coexistence phases, with the phase behavior controlled by density, temperature, and propulsion speed and retaining the main features of the previously studied two-dimensional APM. At weak propulsion, the dense phase forms a slab perpendicular to its direction of motion. With increasing propulsion speed, this morphology persists for the 2-state model, whereas the dense phases for 4 and 6 states reorient and propagate along their longitudinal direction. For the 6-state model, the reoriented dense phase further develops a cylindrical morphology. We also examine the stability of polar liquids against artificially introduced droplets using microscopic simulations and coarse-grained hydrodynamic equations. At high propulsion speeds, counter-propagating droplets can partially modify the initial polar state, while transverse droplets can completely alter it, demonstrating the metastable nature of polar liquids in the three-dimensional active Potts model.
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Quantum Physics

Succinct Arguments for QMA in the Quantum Random Oracle Model

Succinct arguments are a fundamental cryptographic primitive for verifying computational claims with small communication. In the classical setting, succinct arguments for NP can be constructed from unstructured hardness alone (e.g., hash functions) by compiling probabilistically checkable proofs (PCPs) or interactive oracle proofs (IOPs) for NP via the commit-and-open paradigm. In contrast, known succinct arguments for QMA rely on “structured” cryptographic primitives, or on the quantum PCP conjecture. We construct the first succinct argument for QMA in the quantum random oracle model (QROM) without relying on additional cryptographic assumptions or unproven conjectures. This yields succinct arguments for QMA from unstructured hardness alone, showing that ideal hash functions not only suffice for succinct arguments for NP but also for QMA. Underlying our result is an efficiency-preserving transformation that compiles quantum interactive oracle proofs (QIOPs), a recently introduced interactive generalization of quantum PCPs, into quantum arguments for the same language, via a natural quantum commit-and-open paradigm. Our transformation applies to every QIOP with public-query soundness, a notion that we formalize to capture a natural requirement of the commit-and-open paradigm and is satisfied by a known QIOP for QMA. As a key ingredient in our transformation, we formalize and construct extractable vector commitments for quantum states with local openings in the QROM, which may be of independent interest.
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Soft Condensed Matter

Stiffness-dependent Dielectric Relaxation in Thermoreversible Microgels: Effects of Temperature and Strain

We investigate how particle stiffness governs length-scale-dependent relaxation dynamics in dense suspensions of thermoresponsive PNIPAM microgels subjected to temperature variations and large amplitude oscillatory shear. By combining dielectric spectroscopy with rheometric measurements, we directly correlate microscopic polarization fluctuation dynamics with macroscopic mechanical relaxation. Highly crosslinked, stiffer microgels exhibit longer dielectric relaxation times across a broad temperature range and strain-induced slowing down, whereas softer, open-network microgels exhibit nearly strain-independent dielectric dynamics. Below the volume phase transition temperature (VPTT), macroscopic bulk stress relaxation experiments reveal that suspensions of the softest particles relax most rapidly. For the stiffer microgel suspensions, however, the dynamics decouple: bulk stress relaxation speeds up with increasing stiffness even as dielectric relaxation slows down. Above the VPTT, softer particles undergo greater volume collapse, leading to very rapid bulk stress relaxation. Besides exhibiting slower stress decay, stiffer microgel suspensions also undergo shear-induced structural regeneration during the later stages of deformation. These findings demonstrate that particle stiffness and internal architecture govern relaxation pathways across microscopic and macroscopic length scales, thereby providing a framework for designing adaptive soft metamaterials, stress-dissipative coatings, and self-healing robotic materials.
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General Relativity and Quantum Cosmology

Asymptotics of Killing horizons: A Characterization in de Sitter Spacetime

We prove that (n + 1)-dimensional de Sitter spacetime is locally the unique $(\Lambda > 0)$-vacuum spacetime whose Killing horizons intersect the conformal boundary $\mathscr{I}$. The intersection occurs at the isolated essential zeros of the extension of the Killing vector field to $\mathscr{I}$. We then reconstruct all de Sitter Killing vector fields from their boundary value and obtain a characterization of those admitting a Killing horizon in terms of a conformal invariant $\sigma$: $\sigma<0$ characterizes non-degenerate bifurcate horizons, whereas $\sigma = 0$ yields degenerate non-bifurcate horizons. Finally, we derive an intrinsic, conformally invariant formula for the surface gravity of the horizons in de Sitter, $\kappa^2 = |\sigma|$.
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High Energy Astrophysical Phenomena

Search for dark matter annihilation in the Sun using the full ANTARES dataset

Weakly Interacting Massive Particles (WIMPs) are among the most popular candidates for particle dark matter. In certain scenarios, WIMPs could be gravitationally captured into massive celestial objects and then annihilate into Standard Model particles, possibly leading to the emission of neutrinos. The ANTARES neutrino telescope, located in the Mediterranean Sea, is sensitive to neutrinos with energies ranging from a few tens of GeV to the TeV scale, making it well suited to search for the annihilation of WIMPs with masses below a few TeV/c$^2$. One of the closest potential astrophysical sources of neutrinos from WIMP annihilations is the Sun. In this work, a search for high-energy neutrinos originating from the Sun, using the full dataset recorded by ANTARES from 2007 to 2022 was conducted. The analysis yielded no significant evidence for a neutrino excess over the expected background, and upper limits on the WIMP-proton interaction cross section have been obtained, for both spin-dependent and spin-independent processes. These limits are valid for dark matter masses ranging from 35 GeV/c$^2$ to 10 TeV/c$^2$ for the annihilation benchmark channels WIMP$+$WIMP $\longrightarrow$ $b\bar{b},\tau^+\tau^-, W^+W^-$, assuming a 100$\%$ branching ratio for each of these channels. These results improve on those previously obtained by the ANTARES Collaboration by a factor of two-three and are consistent with those reported by other experiments in direct and indirect searches for dark matter.
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All authors A. Albert, S. Alves, M. André, M. Ardid, S. Ardid, J.-J. Aubert, J. Aublin, B. Baret, S. Basa, Y. Becherini, B. Belhorma, F. Benfenati, V. Bertin, S. Biagi, J. Boumaaza, M. Bouta, M.C. Bouwhuis, H. Brânzaş, R. Bruijn, J. Brunner, J. Busto, B. Caiffi, D. Calvo, S. Campion, A. Capone, L. Caramete, F. Carenini, J. Carr, V. Carretero, T. Cartraud, S. Celli, M. Chabab, T. Chiarusi, M. Circella, J.A.B. Coelho, A. Coleiro, R. Coniglione, P. Coyle, A. Creusot, A. F. Díaz, B. De Martino, C. Distefano, I. Di Palma, C. Donzaud, D. Dornic, D. Drouhin, T. Eberl, A. Eddymaoui, T. van Eeden, D. van Eijk, S. El Hedri, A. Enzenhöfer, P. Fermani, G. Ferrara, F. Filippini, L.A. Fusco, S. Gagliardini, J. García-Méndez, C. Gatius Oliver, P. Gay, N. Geißelbrecht, H. Glotin, R. Gozzini, R. Gracia Ruiz, K. Graf, C. Guidi, L. Haegel, H. van Haren, A.J. Heijboer, Y. Hello, L. Hennig, J.J. Hernández-Rey, J. Hößl, F. Huang, G. Illuminati, B. Jisse-Jung, M. de Jong, P. de Jong, M. Kadler, O. Kalekin, U. Katz, A. Kouchner, I. Kreykenbohm, V. Kulikovskiy, R. Lahmann, M. Lamoureux, A. Lazo, D. Lefèvre, E. Leonora, G. Levi, S. Le Stum, S. Loucatos, J. Manczak, M. Marcelin, A. Margiotta, A. Marinelli, P. Migliozzi, A. Moussa, R. Muller, S. Navas, E. Nezri, B. Ó Fearraigh, E. Oukacha, A.M. Păun, G.E. Păvălaş, S. Peña-Martínez, M. Perrin-Terrin, P. Piattelli, C. Poirè, T. Pradier, N. Randazzo, D. Real, G. Riccobene, A. Romanov, A. Sánchez Losa, A. Saina, F. Salesa Greus, D. F. E. Samtleben, M. Sanguineti, P. Sapienza, F. Schüssler, J. Seneca, M. Spurio, Th. Stolarczyk, M. Taiuti, Y. Tayalati, B. Vallage, G. Vannoye, V. Van Elewyck, S. Viola, D. Vivolo, J. Wilms, S. Zavatarelli, A. Zegarelli, J.D. Zornoza, J. Zúñiga

Exactly Solvable and Integrable Systems

Fredholm determinant solutions to the modified KP hierarchy and 2D Toda lattice: isospectral and non-isospectral reductions

We study Fredholm determinant solutions to the first two positive and the first negative members of the modified Kadomtsev-Petviashvili (mKP) hierarchy, together with the bilinear two-dimensional Toda lattice (2DTL) equation. By applying isospectral reductions, we explicitly construct Fredholm determinant solutions for the modified Korteweg-de Vries (mKdV), the modified Camassa-Holm, and the focusing nonlinear Schrödinger equations. Furthermore, we demonstrate that in the non-isospectral case, the reduction from the mKP and 2DTL equations to the non-isospectral negative KdV equation yields solutions characterized by the deformed Bessel determinant.
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Mesoscale and Nanoscale Physics

Nonlinear optical responses of semiconducting graphene nanoribbons: Strong constraint from a hidden symmetry

Nonlinear optical (NLO) responses are powerful tools for probing material structures, as they are highly sensitive to spatial symmetries. For instance, it is well known that having inversion symmetry forbids even-order NLO effects. Here, we show that nonspatial symmetries can also significantly constrain NLO responses. In graphene nanoribbons (GNRs) with bipartite-lattice structures, we identify the approximate bipartite-lattice particle-hole (BLPH) symmetry strongly suppresses even-order NLO effects, even for systems with no inversion symmetry. Importantly, we demonstrate that this approximate symmetry enables the optical generation of nearly pure spin shift currents in ferromagnetic GNRs, with the charge shift currents strongly suppressed. The spin orientation of these photo-induced DC spin currents can be easily tuned by an external magnetic field, providing distinct advantages over previous schemes for generating pure spin shift currents in antiferromagnetic systems. We illustrate our findings using a recently synthesized ferromagnetic Janus GNR. Our results underscore the significance of an overlooked symmetry aspect of NLO responses and highlight magnetic GNRs as promising candidates for spintronic devices.
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All authors Jiawei Ruan, Weichen Tang, Yang-Hao Chan, Chen Hu, Xiaoxun Gong, Steven G. Louie

Instrumentation and Detectors

Quantitative Interleaved-Pulse Acquisition Extends the Range of Isotope-Ratio Measurements in ToF-SIMS

Isotope ratios underpin tracer studies of transport in oxides, battery materials, and biological systems, yet time-of-flight secondary ion mass spectrometry (ToF-SIMS) struggles to quantify ratios whose members differ in intensity by orders of magnitude: a primary-ion pulse long enough to count the minor isotope precisely can saturate the major isotope, whereas a pulse short enough to keep the major isotope linear yields too few minor-isotope counts. We show that multi-pulse-width acquisition yields quantitative isotope ratios when a dose factor measured within each crater links the phases and each isotope is taken only from phases in which it remains linear; we call this quantitative reconstruction interleaved-pulse acquisition. Pulse widths are selected from measured transfer curves and peak shapes. On thermal SiO2, a tuned (6, 35) ns pair achieves the same per-layer precision as short-pulse acquisition with a 13-fold reduction in the number of analysis frames. On 18O-enriched WOx films, interleaving extends the quantifiable range at the low-fraction end by about 14-fold. Across isotope ratios spanning approximately 1:500 to 1:1, the interleaved reconstruction agrees with the corresponding linear reference measurements, showing no measurable bias introduced by interleaving, and natural-abundance ratios of oxygen, strontium and titanium are reproduced within several percent. The method requires no hardware additions and enables depth-resolved isotope-ratio measurements over a wide range within a single crater.
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Mathematical Physics

A posteriori controllability of non-linear remodelling in linear elastic continua

We investigate the a posteriori controllability of remodelling within the framework of Geometric Control Theory applied to continuum systems. Remodelling is described through an isochoric Bilby–Kroner–Lee decomposition, where the internal structural transformation is represented by a remodelling tensor and its evolution is governed by a stress-driven constitutive law. Assuming infinitesimal deformation and remodelling stretches, while retaining finite rotations of the principal remodelling directions, we derive a nonlinear state-space representation in terms of principal remodelling stretches and orientation variables. This formulation allows the remodelling process to be interpreted as a finite-dimensional nonlinear control system parametrised by the material position. Equilibrium configurations are characterised, and under-actuated controllability problems are studied by means of the tools of Geometric Control Theory. The three-dimensional setting shows that the nonlinear coupling between remodelling stretches and orientations enables complete steering of the internal state through a reduced number of independent controls, while the planar reduction reveals a loss of controllability despite the presence of nonlinearity. The results provide a first systematic investigation of remodelling controllability and further support the development of Continuum Control Theory as a framework for the analysis and design of controlled internal structural transformations in continuous media.
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Plasma Physics

Global Phase Locking in Superradiant Chorus Emissions

Coherent wave amplification in inhomogeneous systems is usually described in terms of resonance and nonlinear phase locking, but these local phase conditions do not determine how the wave amplitude evolves when the resonance condition changes during wave propagation. Here we identify a global phase-locking principle, in which the stable resonant phase remains nearly unchanged as the resonance detuning evolves. This condition requires the wave amplitude to track the evolving detuning and leads to linear amplitude growth with distance, producing the quadratic intensity scaling characteristic of superradiant emission. We demonstrate this mechanism using self-consistent kinetic simulations of whistler-mode chorus waves, one of the most important coherent electromagnetic emissions in Earth's magnetosphere. The simulated chorus amplitude and effective growth rate follow the predicted superradiant scalings, rather than exponential growth. Direct phase-space analysis further shows that the resonant electron trapping island remains centred at an approximately fixed phase during amplification. These results identify global phase locking as the dynamical origin of superradiant chorus growth and reveal a general phase-organization principle for coherent radiation in evolving resonant systems.
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Materials Science

Topological Hall Effect Induced by Chiral Spin Textures at the Ferroelectric/Ferromagnetic Interface

Chiral spin textures, largely driven by the Dzyaloshinskii-Moriya interaction, offer significant potential for next-generation computing technologies due to their chirality and topological stability. Ferroelectric/ferromagnetic van der Waals heterostructures are particularly appealing because they can combine interfacial inversion-symmetry breaking and spin-orbit coupling to promote interfacial Dzyaloshinskii-Moriya interaction, while switchable ferroelectric polarization provides a nonvolatile tuning knob. This study investigates interfacial chiral spin textures in few-layer Fe$_3$GeTe$_2$/$\alpha$-In$_2$Se$_3$ heterostructures. Two groups of topological Hall signals are identified just below and above the coercive field, and thickness-dependent transport reveals a notable reduction in critical temperature with increasing Fe$_3$GeTe$_2$ layer thickness. Low-temperature magnetic force microscopy images reveal two types of magnetic bubbles with opposite magnetic contrasts near the coercive field, each associated with distinct topological Hall signals. Together with atomistic spin-dynamics simulations and first-principles calculations, these results support the formation of interfacial DMI-stabilized chiral spin textures. Switching the ferroelectric polarization of the $\alpha$-In$_2$Se$_3$ layer further enables nonvolatile modulation of both anomalous and topological Hall effects. The resulting ferroelectric and magnetic bistabilities generate four distinguishable Hall resistance states programmable by electric and magnetic fields. These findings highlight the potential of van der Waals interfaces for advanced device applications.
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All authors Jingkuan Xiao, Yaqing Han, Jianfeng Guo, Renjun Du, Jiawei Jiang, Baoshan Cui, Runnong Zhou, Siqin Wang, Siqi Jiang, Fuzhuo Lian, Di Zhang, Guodong Ma, Jiabei Huang, Zhaochen Qu, Wanting Xu, Kenji Watanabe, Takashi Taniguchi, Alexander S. Mayorov, Jinsheng Wen, Haifeng Ding, Gong Chen, Ahmet Avsar, Hongxin Yang, Lihong Bao, Hong-Jun Gao, Shiyu Zhu, Lei Wang, Geliang Yu

Computational Physics

Geometry-Controlled Chern transfer and Flat Band Reconstruction in distorted kagome lattices

Flat band formation and nontrivial topology are central manifestations of kagome electronic structure, yet they are commonly discussed in idealized lattice geometries. In distorted kagome materials, structural deformation reorganizes electronic propagation pathways, but a microscopic understanding of how such distortions govern flat band dispersion and band topology is still lacking. Using a distorted kagome tight-binding model with rotated angle dependent long-range hopping and intrinsic spin-orbit coupling, we show that distortion reconstructs both the dispersion and topology of the kagome band manifold. The flat band descendant develops distinct bandwidth regimes associated with a redistribution of its extrema in momentum space. Simultaneously, symmetry-related band inversions generate quantized Chern number transfer whose parity is fixed by the multiplicity of the touching points, thereby determining the gap-resolved Z2 topology. The accompanying Berry curvature evolution produces characteristic anomalous Hall and Nernst responses. These results identify geometric deformation as a common microscopic origin of flat band and topological reconstruction in kagome systems.
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High Energy Physics (Theory)

Quantum states in an AdS-invariant theory

We note that the description of elementary particles in anti-de Sitter (AdS) quantum theory differs radically from standard approaches. Since the Cartan subalgebra of the AdS algebra has rank 2, it is necessary to consider only those elements that explicitly depend on the eigenvalues of operators in the irreducible representations (IRs) of the algebra. In the literature, AdS symmetry is widely invoked in various quantum applications, such as AdS/QCD. However, such frameworks typically do not take into account the unconventional properties of the AdS algebra IRs investigated in the present paper.
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Mathematical Physics · Cross-listed from math.AP

Sharp stability and instability of stratified steady states for the incompressible porous media equation

We study the stability and instability of stratified steady states $\rho_s=\rho_s(y)$ for the two-dimensional incompressible porous media equation on $\mathbb{T}\times(-1,1)$ and $\mathbb{T}\times\mathbb{R}$. On the periodic channel, uniformly decreasing steady states satisfying natural boundary-compatibility conditions are nonlinearly stable under small $H^m$ perturbations, for every integer $m>2$. The solutions converge in $L^2$ to the measure-preserving stratification of the initial density at the rate $t^{-m/2}$. Conversely, every steady state with $\sup\rho_s'>0$ is nonlinearly unstable in $H^m$. On the infinite cylinder, we prove nonlinear instability under the additional gap condition \[ \sup_{\mathbb{R}}\rho_s' >\limsup_{|y|\to\infty}\rho_s'(y). \] In both settings, the instability is generated by positive eigenvalues of the linearized operator converging to $\sup\rho_s'$, which equals both its spectral bound and semigroup growth bound.
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High Energy Physics (Theory)

Multipartite Entanglement Can Probe Wormhole Moduli Invisible to Bipartite Entanglement

In a companion paper, we found that near the untwisted point of a four-boundary AdS$_3$ wormhole, whenever the complete bipartite Ryu-Takayanagi entropy vector is insensitive to a Fenchel-Nielsen twist, the holographic $\mathtt q=4$ multi-entropy is insensitive as well. Here we show that the situation changes at finite twist. The twist lengthens the crossing geodesics and thereby enlarges the region in which all bipartite RT entropies remain invariant. In part of this enlarged region, a twist-sensitive $\mathtt q=4$ network becomes globally minimal. We thus find an open region of wormhole moduli space in which the complete bipartite RT entropy vector is exactly unchanged while the $\mathtt q=4$ multi-entropy detects the twist. Our result provides an explicit example in which the $\mathtt q=4$ genuine multi-entropy probes bulk geometric information invisible to all bipartite entanglement entropies.
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High Energy Physics (Theory)

Can Multipartite Entanglement Probe Wormhole Moduli Invisible to Bipartite Entanglement?

We ask whether multipartite entanglement can probe bulk moduli invisible to bipartite entanglement. We study this question in an explicit family of four-boundary AdS$_3$ wormholes related by a Fenchel-Nielsen twist $\tau$, asking whether the complete set of bipartite RT entropies can remain exactly $\tau$-independent while the holographic $\mathtt q=4$ multi-entropy is sensitive to the twist. Within the class of configurations analyzed here, for sufficiently small $|\tau|$, we find no such regime along the symmetric line $\ell=m$: the globally minimal $\mathtt q=4$ network is itself exactly $\tau$-independent throughout the parameter range analyzed. This conclusion is not a priori obvious: it emerges from a competition among several admissible configurations whose relative ordering changes multiple times as the geometry is varied, and persists up to the point where the bipartite RT entropies themselves become twist-sensitive.
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General Relativity and Quantum Cosmology

Scaling RIFT 1: Extending RIFT to third-generation gravitational-wave analyses

Interpretation of compact binary signals observed by third-generation gravitational-wave detectors is complicated by their high signal-to-noise ratios, often reaching hundreds to thousands, and by time- and frequency-dependent detector responses arising from Earth's rotation and the detectors' large physical extent. Building on prior work for LISA, we implement generic, robust extensions of the RIFT parameter estimation pipeline that enable interpretation of these sources using any existing waveform model, without recourse to intermediate pretrained data products like reduced-order approximations or normalizing flows. We demonstrate end-to-end recovery of finite-size binary-neutron-star injections in a three-site next-generation network to $\mathrm{SNR}=1000$, localizing the source's extrinsic parameters to $0.8\times10^{-3}\,\mathrm{deg}^2$ in minutes on a single GPU.
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All authors R. O'Shaughnessy, A. Jan, J. Lange, R. Mechum

Mathematical Physics · Cross-listed from math.CO

Elementary Askey-Wilson Functions

We present a determinantal evaluation formula for the very-well-poised ${}_8\Phi_7$ basic hypergeometric Askey-Wilson function in terms of elementary functions. The formula in question is valid for discrete values of the four permutation-symmetric Askey-Wilson parameters; specifically, these consist of all quadruples of parameter values that are given, up to a sign, by powers $q^k$ with $k$ a positive integer or half-integer, in such a way that each of the four types (positive/negative sign, integer/half-integer power) occurs exactly once. The proof hinges on a product formula for an associated Cauchy-type determinant, which is of independent interest and is established here by elementary means using Krattenthaler's `identification of factors' method for determinant evaluations.
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Chemical Physics

Ionization-Driven Dehydrogenation and Molecular Growth in Gas-Phase Adamantane Clusters

We investigate fragmentation and molecular growth induced by keV ions in initially neutral gas-phase adamantane clusters, the simplest diamondoid molecule (Ad, C$_{10}$H$_{16}$). Using time-of-flight mass spectrometry in combination with quantum-chemical calculations, we find that intact cluster cations undergo extensive dehydrogenation. We also observe a distinct distribution of singly charged products with masses predominantly between those of the adamantane monomer and dimer cations. We attribute these species to ion-induced growth products and interpret their formation considering the smallest cluster cation, [Ad]$_2^+$, using quantum-chemical calculations. Our results demonstrate that ionization strongly reorganizes the dimer geometry, facilitating H$_2$ elimination and intermolecular covalent C–C bond formation. Weakly bound adamantane clusters are thereby transformed into covalently bound carbonaceous species with a strong preference for specific molecular structures. These findings provide new insight into ionization-driven molecular growth in saturated hydrocarbon systems contributing to the understanding of molecular complexification, with implications for chemical physics and astrochemistry.
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All authors Sumit Srivastav, Per Eng-Johnsson, Raimund Feifel, Alicja Domaracka, Patrick Rousseau, Dariusz G. Piekarski, Sylvain Maclot

Quantum Physics

Consistent histories and the ultrametric on infinite tensor products

The consistent histories formulation of quantum mechanics assigns classical probabilities to sequences of coarse-grained events when the corresponding interference terms vanish. In finite models these terms generically need not vanish exactly, and their smallness alone supplies no asymptotic geometry on the space of histories. We construct such a geometry for histories that accumulate quantum records. When the normalized Dowker - Halliwell interference between two histories factorizes as the cumulative fidelity of their records, its decay is controlled by the accumulated squared Bures distance. In the infinite registration limit, the Kakutani - von Neumann dichotomy gives a sharp sector alternative: summable Bures defect yields weakly equivalent record sequences, whereas nonsummable defect produces orthogonal superselection sectors and vanishing normalized interference. The convergence exponent of the Bures defect defines a pseudo-ultrametric on histories. After quotienting its zero distance degeneracy, it becomes a complete ultrametric, requiring neither compactness of the outcome space nor continuity of the record family, and coincides with the gauge invariant sector metric $\tilde d$ introduced in \cite{LesTP}. Its value, the consistency rate, has three equivalent interpretations: it is the sector separation metric, the polynomial growth exponent of the negative logarithm of normalized interference, and, by the Helstrom formula, the corresponding exponent of the negative logarithm of the minimum error probability for discriminating the cumulative records. Classical separation profiles determine the rate: positive long time mean defect gives the maximal value $\delta=1$, while the borderline profile $d_m^2\asymp m^{-1}$ produces distinct superselection sectors at zero polynomial rate, $\delta=0$.
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High Energy Physics (Phenomenology)

CGC Fit to HERA DIS and Forward Hadron Production in p+p Collisions

Many experiments have provided possible hints of gluon saturation, including geometric scaling in deep inelastic scattering (DIS) at HERA, the suppression of forward particle yields in d+Au collisions relative to p+p collisions at RHIC, and the suppression of away-side peaks in di-hadron correlations at forward rapidities in proton-nucleus collisions at RHIC and the LHC. Previous studies within the Color Glass Condensate (CGC) framework have primarily focused on fits to HERA deep inelastic scattering data, using the resulting dipole amplitudes to predict hadronic observables in proton-nucleus and proton-proton collisions. A simultaneous fit of DIS and forward particle production data, and a systematic study of their interplay, has so far been absent. In the work presented here, we focus on two processes: inclusive DIS and forward single inclusive hadron production in p+p collisions, incorporating data from HERA, RHIC, and the LHC. We solve the Balitsky-Kovchegov (BK) small-x evolution equation and perform a global fit to the combined datasets. Our analysis accounts for uncertainties in fragmentation functions and provides final uncertainties for the fitted parameters. The outcomes demonstrate the potential of the CGC formalism to provide a universal description of these diverse processes at the level of the dipole amplitude. In these proceedings, after very briefly summarizing the setup and our results, we highlight one particular aspect of the analysis, namely the complete uncertainty treatment. We validated the final uncertainties with two independent methods: the Hessian method and the Bayesian inference method, finding very good agreement.
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All authors Piotr Korcyl, Truong My Hau Le, Farid Salazar, Tomasz Stebel

Quantum Physics

A Memory-Magic Exchange Law in Streaming Clifford+T Compilation

A phase that reaches a fault-tolerant processor in additive pieces can be remembered until the last piece arrives, or executed on arrival: the first option costs classical memory carried across rounds, the second costs magic states committed before the phase is known. We determine the exchange rate $\alpha$, committed $T$ gates per bit of memory forgone, for ancilla-free coordinatewise Clifford+$T$ compilation. The Ramanujan bound gives $\alpha\ge2$ with explicit constants, the square-root barrier of the spectral method. An elementary determinant method, using that quaternion numerators lie on spheres in both real embeddings of $\mathbb{Q}(\sqrt2)$, counts words near any rotation coset below that barrier. With a height dichotomy for the sphere sections it produces and a fibration over rational projections, it gives every $\alpha<5/2$ unconditionally and uniformly over frames, by an exact SMT check of its continuum case analysis; $5/2$ is where this method stops. At Clifford-framed cosets the volume law holds up to subexponential factors: all but a vanishing fraction of $z$-rotations need $T$-count $(3-o(1))\log_2(1/\varepsilon)$, and processes whose committed pieces are near Clifford-framed $z$-rotations, including per-rotation pipelines, have $\alpha\ge3-o(1)$, which a fractional-passthrough family attains under the Ross-Selinger typical-cost hypothesis. Under an equidistribution conjecture supported by exhaustive enumeration to $T$-count 22, $\alpha=3$ in general and memory should be shed in whole rotations. The bounds hold even when the phases cancel to the identity; side information enters through a conditional entropy; probabilistic mixing halves the costs but not the rate. With clean ancillas and a phase-gradient catalyst, table lookups batched over coordinates drive the rate to $O(1/\log\log(1/\varepsilon))$, so the constant-rate law is specific to coordinatewise synthesis.
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Mathematical Physics · Cross-listed from math.SP

Periodic graph operators with reducible dispersion polynomials for all potentials

We give a complete characterization of periodic graph operators whose dispersion polynomials are reducible for every potential. Consequently, the reducibility dichotomy for parameter-dependent Laurent polynomials implies that, for every other periodic graph operator, the dispersion polynomial, and hence the Bloch variety, is irreducible for generic potentials. Our proof proceeds through two reductions. We first use the monodromy of the roots of the dispersion polynomial with respect to the potential parameters to reduce the problem to the splitting case. We then show that the splitting property passes to the principal submatrices of the Floquet matrix, reducing the problem further to the case that the fundamental domain contains two vertices.
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Astrophysics of Galaxies

The ALPINE-CRISTAL-JWST Survey: Investigating the role of interstellar dust, gas and stars in high-z galaxies at kpc-scales

A comprehensive understanding of galaxy evolution requires a detailed analysis of gas and dust, their distribution, and evolution within galaxies. We analyse spatially resolved (~kpc) rest-frame [CII] and dust continuum ALMA observations together with JWST/NIRSpec IFU data of a sample of galaxies at z~4-5. We focus on deriving the spatial distributions of atomic and molecular gas masses, dust and stellar masses, star formation rates (SFR), and metallicity. The oxygen abundance maps have values in the range of 12+log(O/H)~8.1-8.3 with variations of the order of 1dex within the same galaxy. The calibration used in this study to estimate the atomic gas mass in our galaxies seems to overestimate the atomic gas mass surface densities up to 1-2 orders of magnitude. However, a calibration based on a spatially resolved [CII] conversion factor gives a more robust estimation of the total gas mass. Galaxies exhibiting signatures of strong outflows have lower dust-to-stellar surface mass density ratio and lower gas mass fractions than the galaxies with no outflow signatures. While the latter is consistent with these galaxies ejecting part of their gas reservoir to the circumgalactic medium, the low dust-to-stellar surface mass density ratios also suggest that part of the dust content is expelled outside the galaxy, which reinforces previous theoretical suggestions of dust removal by stellar feedback or radiation pressure to explain the high UV luminosities in galaxies at very high-redshifts. Some galaxies of our sample have almost an order of magnitude higher dust-to-gas and dust-to-stellar surface mass density ratio than galaxies in the local Universe, suggesting that a large dust reservoir has been built up already at time scales of ~1 Gyr in these galaxies.
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All authors F. Lopez, M. Relano, I. De Looze, A. L. Faisst, R. Herrera-Camus, R. A. Jorgenson, E. Pérez-Montero, M. Palla, C. Accard, R. O. Amorin, M. Aravena, R. J. Assef, A. J. Battisti, M. Boquien, E. da Cunha, P. Dam, R. L. Davies, M. Dessauges-Zavadsky, A. Ferrara, S. Fujimoto, M. Ginolfi, N. Gutierrez-Vera, A. Hadi, E. Ibar, H. Inami, A. M. Koekemoer, L. L. Lee, J. Li, J. Molina, A. Nanni, D. Narayanan, F. Pozzi, F. Rizzo, M. Romano, D. B. Sanders, P. Sawant, L. Vallini, S. A. van der Giessen, V. Villanueva, G. Zamorani

Disordered Systems and Neural Networks · Cross-listed from q-bio.NC

An adaptive fractional state links circuit mechanisms to cortical dynamics across the visual hierarchy

Cortical circuits must respond flexibly to new inputs while integrating information about the past, yet the way in which neural activity reconciles these competing demands remains unclear. Combining Neuropixels recordings from six mouse visual areas with mechanistic circuit modeling, we identify a dynamical regime in which heavy-tailed superdiffusive fluctuations coexist with long-range temporal dependence and oscillations. We formalize this regime as the adaptive fractional (AF) state, using an effective mean-field theory in which spatial and temporal fractional derivatives capture heavy-tailed excursions and long-range memory, respectively. We find that dynamical exponents characterizing the AF state vary systematically across the visual hierarchy: higher visual areas exhibit weaker superdiffusion and stronger temporal memory. In the circuit model, this hierarchical shift emerges from a progressive weakening of effective inhibition. These findings extend the classical hierarchy of timescales to a hierarchy of dynamical regimes and suggest that the AF state allows cortical areas to jointly express rapid responses and long-term temporal integration.
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High Energy Physics (Phenomenology)

Generalized parton distributions of the nucleon in the chiral quark soliton model: Sum over all quark states at nonzero skewness and momentum transfer

We compute the combinations $E_M=H^{u+d}+E^{u+d}$ and $H_E=H^{u-d}+tE^{u-d}/(4M_N^2)$ of unpolarized generalized parton distributions (GPDs) of the nucleon in the chiral quark soliton model at nonzero skewness $\xi$ and nonzero momentum transfer $t$. The combinations contain the GPDs $H^{u-d}$ and $E^{u+d}$, which are subleading in the expansion in the inverse number of colors. Both combinations are double sums over the quark states. A multipole expansion of the light-cone operators makes the sums computable at every $\xi$ and every $t\le0$. The contribution of the Dirac continuum is summed over the quark states, without an interpolation formula and without a gradient expansion. The first moments satisfy the form-factor sum rules, and the second moments satisfy polynomiality.
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High Energy Physics (Theory)

Relic of the Kink Shape Mode in a Topological Thick Brane - some implications

The kink soliton provides a simple construction of a topological thick 3-brane sourced by a minimally coupled canonical scalar field in five-dimensional general relativity. Although the flat-space kink is a solution of $\varphi^4$ theory, the gravitating configuration requires $M_*$-suppressed $\varphi^6$ corrections to support a stable warped geometry. Unlike its flat-space counterpart, the scalar perturbation spectrum contains no normalizable bound state. We nevertheless identify a single quasi-bound, or resonant, mode. Using a time-independent relative-probability analysis, direct time evolution, and a four-turning-point WKB calculation, we establish a direct connection between this resonance and the massive bound shape mode of the flat-space $\varphi^4$ kink. We also show that, within an EFT-consistent parameter window, the resonance can transfer energy from bulk geometric fluctuations to localized matter, thereby allowing the possibility of high-scale reheating in the early universe.
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Mathematical Physics · Cross-listed from math.AP

Optimal Hardy Inequalities for Fractional $p$-Laplacians on the Integers

We obtain optimal Hardy inequalities for fractional powers of the $p$-Laplacian $\Delta_p^\sigma$ on $\mathbb{Z}$, $p\in (1,\infty)$, $\sigma \in (0, 1/p)$. Asymptotically, the optimal weights behave like $|x|^{-p\sigma}$ as $|x|\to \infty$. We show a similar result for the Riesz fractional $p$-Laplacian. In an appendix, we show that for general $p$-Laplace operators on locally summable graphs, $p$-null-criticality implies $p$-optimality at infinity.
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