General Relativity and Quantum Cosmology
Energy Flux as an Entanglement Current in Moving-Mirror Radiation
Yasusada Nambu and Riku Yoshimoto
In this work, we investigate the
quantum entanglement properties of analog Hawking radiation produced by a moving mirror. Using two detector modes defined through window functions on a
quantum field, we quantify the bipartite
entanglement established between these modes. Our results reveal that the amount of
entanglement accessible to the detectors increases when the mirror follows trajectories with non-monotonic, time-dependent acceleration, which are accompanied by the emission of negative energy flux. This indicates that the negative energy flux acts as a channel through which information can be returned. To substantiate this perspective, we examine how the recovery or reconstruction of the associated partner modes is related to the negative energy flux emitted by the mirror.
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Fluid Dynamics
The spectral picture of self-similar collapse in the Constantin-Lax-Majda equation
Jie Xu
We give a spectral description of the self-similar collapse profile of the Constantin-Lax-Majda (CLM) equation, the $a=0$ anchor of the generalized family $w_t + a\,u\,w_x = u_x\,w$, $u_x = Hw$. Linearizing about the exact profile $\Omega(y) = -y/(y^2+1/4)$ and realizing $L_0$ as a closed operator on the origin-$H^2$ space, we prove three things at $a=0$. Its essential spectrum meets the closed half-plane $\{\mathrm{Re}\,\lambda \ge -1/2\}$ in the single vertical line $\{\mathrm{Re}\,\lambda = -1/2\}$: the line is placed by a log-widening Weyl sequence, and an explicit Hardy-Mellin resolvent bound constructively empties the rest of the half-plane apart from $0$ and $1$. Its full point spectrum over $\mathbb{C}$, on the odd realization, is exactly $\{0,1\}$, the scaling and time-shift
symmetry modes, with no embedded
eigenvalues; removing these by the standard modulation leaves a spectral gap of $1/2$ on $X$. The linear
semigroup and its exact decay rate $e^{-\tau/2}$ are computed in closed form, but on a weighted space of the conjugated variable reached from $X$ by a bounded transfer map; we keep the two separate, since $L_0$ is non-normal and a spectral gap does not by itself give a decay rate in the $X$ norm. A realization dichotomy identifies the in-strip smear of generic discretizations as the faithful spectrum of the maximal $L^2$ realization, which origin-$H^2$ removes. For $a>0$ we prove a conditional two-line inclusion for each admissible smooth focusing profile, recompute the branch $c_l(a)$ of Lushnikov, Silantyev, and Siegel as a cross-check, and record the formal scaling-relevance exponent $s^*(a) = 1/c_l(a)$, below which fractional dissipation is asymptotically subdominant in self-similar variables for fixed sufficiently regular data. The contribution is the realization-dependent spectral picture of the collapse profile itself.
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Solar and Stellar Astrophysics
2D hydrodynamical simulations of Be star decretion disc formation through boundary layer effects
Madeline Overton, Zhaohuan Zhu, Rebecca G. Martin et al. (+1 more)
Be
stars are massive main-sequence
stars rotating close to their breakup rate. They possess a decretion disc of material built up due to mass loss from the
star, however, there is not a consensus to the mechanism responsible for the formation of the disc because of their sub-breakup
spin rates. We present the first 2D hydrodynamical simulations of the formation of a Be
star decretion disc from a rapidly rotating
star due to boundary layer effects that reduce the rotation rate of the disc close to the
star. In our simulations with a disc aspect ratio of $h/r=0.1$, a decretion disc forms around a
star rotating with $80 \%$ of the breakup rate, but fails when rotating at $70 \%$ of the breakup rate. For a thinner disc, a faster
stellar spin may be needed to form a dynamically important decretion disc. We also demonstrate good agreement between 1D and 2D models. Although this work does not consider the presence of
magnetic fields and the angular momentum transport is through viscosity, our results robustly show a Be
star disc may be built up hydrodynamically through boundary layer effects, and may play an essential role in regulating the
stellar spin.
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All authors Madeline Overton, Zhaohuan Zhu, Rebecca G. Martin, Jiayin Dong
Earth and Planetary Astrophysics
CAFE follow-up of TESS hot Jupiter candidates left behind: I. Five newly confirmed planets and a false positive
J. Lillo-Box, C. Cifuentes, O. Balsalobre-Ruza et al. (+56 more)
Hot Jupiters are key targets for understanding
planet formation, migration, and atmospheres. Yet, most ground-based follow-up resources for the TESS mission are focused on confirming low-mass
planet candidates, leaving many
giant planets without mass determinations or definitive confirmation. We use the \cafe{} spectrograph at Calar Alto Observatory to monitor the radial velocity of
stars hosting hot-Jupiter candidates that have received little follow-up, aiming to confirm their planetary nature. We present results for seven candidates. We monitored the radial velocity of TOI-603, TOI-1137, TOI-1837, TOI-2114, TOI-4492, TOI-5806, and TOI-5811, jointly modeling the CAFE radial velocities and TESS photometry to determine the nature and properties of the transiting objects. We confirm five new
planets: TOI-603 b ($33.0^{+6.5}_{-6.2}$ M$_{\oplus}$, $16.2$ d), TOI-2114 b ($1.01^{+0.14}_{-0.12}$ M$_{\rm Jup}$, $6.2$ d), TOI-4492 b ($5.92^{+0.67}_{-0.64}$ M$_{\rm Jup}$, $4.4$ d), TOI-5806 b ($2.77^{+0.34}_{-0.32}$ M$_{\rm Jup}$, $3.2$ d), and TOI-5811 B b ($0.81^{+0.11}_{-0.10}$ M$_{\rm Jup}$, $6.3$ d). TOI-603 b lies in the "Neptune savanna", whereas the other four are hot Jupiters orbiting slightly evolved
stars. We find TOI-5811.01 to be a
planet transiting the nearby bound companion TOI-5811 B (hence TOI-5811 B b), and identify a
stellar companion to TOI-5806 at a projected separation of 248 au, making both S-type planetary systems. TOI-1837.01 is an eclipsing binary, while TOI-1137.01 remains inconclusive. The five confirmed
planets orbit bright
stars (${\rm G}=8.6-10.2$~mag), and four are excellent targets for atmospheric studies, with transmission spectroscopy metrics above 90. These results highlight the importance of intensive follow-up observations to establish the nature of transiting
planet candidates.
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All authors J. Lillo-Box, C. Cifuentes, O. Balsalobre-Ruza, B. Montesinos, D. Latham, K. A. Collins, D. Ciardi, G. Hébrard, S. W. Yee, E. W. Guenther, H. Bouy, J. N. Winn, S. B. Howell, C. Ziegler, M. E. Everett, B. Safonov, F. Murgas, N. Narita, L. D. Nielsen, A. Abreu, J. Aceituno, J. F. Agüí Fernández, M. Azzaro, D. Barrado, P. Benni, A. Bieryla, A. Chontos, C. A. Clark, E. Delgado-Mena, S. J. Deveny, R. Forés-Toribio, J. Flores-Martín, A. Garmash, S. Góngora, J. D. Hartman, C. Haukes, N. Heidari, I. J. Helm, J. F. Kielkopf, J. Köhler, C. Littlefield, M. B. Lund, B. Massey, A. Masson, J. McCormac, M. Morales-Calderón, M. Mori, J. A. Muñoz, E. Pallé, P. Plavchan, M. Reefe, J. E. Schlieder, G. Srdoc, C. Stockdale, J. C. van Eyken, R. G. West, F. P. Wilkin, J. Wittrock, D.-V. Zora
General Relativity and Quantum Cosmology
Analytical Criteria for Black Hole Instability in Non-Minimally Coupled Scalar-Tensor Theories
Majid Karimabadi, Davood Mahdavian Yekta and S. A. Alavi
In this paper, we show that the robustness of black hole stability is not preserved when perturbations are subjected to critical values of the coupling constant in two non-minimally coupled scalar-tensor models, particularly for several regular black holes. Our main result is the derivation of a general near-horizon analytical criterion for the onset of instability, which yields analytical expressions for the critical coupling constants in both coupling models. Numerical time-domain analysis shows that these critical values are coincident with the threshold points of the field perturbation profiles. At the critical coupling, the effective potential of the Regge-Wheeler equation develops an extremum exactly at the location of event horizon. We further show that, in the near-horizon regime, the real parts of the quasi-normal frequencies vanish, giving rise to purely imaginary modes. Finally, we recover the universal area quantization of spherically symmetric black holes at the critical coupling without resorting to the highly damped-mode approximation, and show that the result is independent of the particular non-minimal coupling model.
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Cosmology and Nongalactic Astrophysics
Constraining Effective Viscosity in the Intracluster Medium via the Thermal Sunyaev-Zeldovich Effect – Predictions from the SLOW Constrained Coma Cluster Simulations
Frederick Groth, Yuan Li, Joseph Golec et al. (+4 more)
We study the effect of viscosity on the Sunyaev-Zeldovich signal in a simulated constrained Coma cluster analog. We aim to provide alternative constraints on the amount of viscosity in the ICM. We use the Coma cluster realization with different levels of viscosity from the LOWER DECKS zoom-ins of the SLOW constrained simulations. We generate mock thermal and kinetic Sunyaev-Zeldovich maps and and analyze their statistics. We compare them to Planck observations. Viscosity shows a consistent trend in thermal SZ (tSZ) profiles, increasing the signal in the center and suppressing it in the outskirts. Viscosity also has a strong effect on the tSZ power spectrum, elevating its amplitude on all scales. Comparisons with Planck observations suggest that the effective ICM viscosity is below $5\%$ of the Spitzer value. Unsharp masking reveals an effect on small scales, which are, however, not yet detectable with current observational data. The thermal Sunyaev-Zeldovich effect shows clear and consistent trends that allow us to probe the effective viscosity of the ICM. Our analysis suggests suppressed ICM viscosity below $5\%$ of the Spitzer value, consistent with previous X-ray analysis. Our results validate the strength of the SZ effect as an independent method to constrain ICM viscosity.
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All authors Frederick Groth, Yuan Li, Joseph Golec, Benjamin A. Seidel, Jenny G. Sorce, Tirso Marin-Gilabert, Klaus Dolag
High Energy Physics (Experiment)
Machine Can Automatically Discover Parametric Functions to Model HEP Data
Ho Fung Tsoi, Dylan Rankin, Cecile Caillol et al. (+5 more)
In HEP data analyses, finding an adequate function to model binned data has largely relied on a manual process: guess a functional form by intuition, fit, examine, then repeat until successful. We show that this iterative process can be automated by a machine using symbolic regression, which performs a data-driven search over function space without requiring prior knowledge of what an adequate function should look like. We present the SymbolFit package, which pairs symbolic regression with uncertainty modeling to target HEP analysis use cases, and demonstrate it on the CMS and ATLAS Run 2 dijet spectra: 560 independent seeded runs across seven simple fit configurations generated over 1000 functions fitting the spectra with $\chi^2/\text{NDF}\approx 1$, and 111 of the runs rediscovered the very dijet and UA2 functions used in published dijet searches.
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All authors Ho Fung Tsoi, Dylan Rankin, Cecile Caillol, Miles Cranmer, Sridhara Dasu, Javier Duarte, Philip Harris, Elliot Lipeles
High Energy Physics (Theory)
Resolved Maxwell-Boundary Normal Forms and Exact Reentrant Scaling in Accelerating AdS Black Holes
Ruiliang Li
Reentrant phase transitions of accelerating anti-de Sitter black holes are known numerically, but their apparent loss at small string tension has lacked an analytic explanation. In the single-string ensemble at fixed pressure, charge, and tension, we solve the unrestricted two-phase Maxwell-turning problem for the charged slowly accelerating C-metric. Elimination forces the two horizon coordinates to coincide and yields a closed one-parameter locus. An exhaustive enumeration of the remaining
equilibria establishes global phase selection throughout the physical black-hole sector. The locus exists for $0<\mu<0.202602$, with no positive lower threshold. As $\mu\to0$, the pressure and temperature widths of the reentrant window contract as the fourth and third powers of the tension, while the
entropy gap and latent heat diverge. A two-chart blow-up gives a parameter-free limiting profile and identifies thermodynamic-volume inversion as the turning mechanism between two distinct noncritical phases. At a Maxwell boundary with fixed sheet incidence, projective Newton data of the thermodynamic jumps determine the leading coexistence profile. Their positive simple roots fix the turn count, order, and
curvature signs; the C-metric realizes the primitive binomial class.
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Quantum Physics
The Quantum Adiabatic Theorem for Non-Hermitian Dynamics
G. M. V. S. Aponso, B. P. W. Fernando, K. K. W. A. S. Kumara et al. (+1 more)
We establish a quantitative adiabatic estimate for a class of finite-dimensional non-Hermitian Schrödinger dynamics. The original non-Hermitian
Hamiltonian is assumed to be diagonalizable with real spectrum and non-crossing
eigenvalues. We then construct a dynamically compatible time-dependent metric operator, and its positive square root defines a Dyson map. The associated Dyson-transformed
Hamiltonian is Hermitian. When this Dyson-transformed
Hamiltonian satisfies the Hermitian adiabatic assumption, the standard resolvent-projection method gives an explicit adiabatic estimate in the Hermitian representation. Pulling this estimate back through the Dyson map gives an approximation in the original non-Hermitian representation. The resulting Dyson-pulled-back projections are then compared with the spectral projections of the original non-Hermitian
Hamiltonian by using a contour-resolvent estimate. The final bound contains two contributions: the pulled-back Hermitian adiabatic error and the projection-comparison error. A two-level non-Hermitian model is presented to illustrate the hypotheses of the
theorem and the two contributions appearing in the final estimate.
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All authors G. M. V. S. Aponso, B. P. W. Fernando, K. K. W. A. S. Kumara, R. P. K. De Silva
Solar and Stellar Astrophysics
One cluster, two clusters, no cluster? – The curious case of HSC 2686 and Lynga 3
Andreas Ritter, Quentin A. Parker, Xizhe Xie et al. (+1 more)
This study was motivated by the search for Planetary Nebulae (PNe) and Open Cluster (OCs) associations. Only 5 PNe are currently in
Galactic OCs among the previous $\sim4,800$ OCs known. They are valuable because as cluster members their properties can be linked to their progenitor
stars, something not possible for general field PNe. Since the
GAIA astrometric satellite first data release, thousands of new OC candidates have been identified. This offers fresh motivation to search them as hosts for known PNe. Statistically we expect 30 OC-PN pairs to be present. We searched these
GAIA candidate OCs, found by Hunt & Reffert (2023), for known central
stars of PNe (CSPNe) as a practical proxy for the PNe themselves and one suited to automated searches. We identified 1 potential CSPN (IRAS 15127-5811) of "Likely" PN [GKF2010] MN18 in the HASH database, as a claimed member of the putative cluster HSC~2686. A second cluster (Lynga~3) with similar parameters and in very close angular proximity could also be a potential host. Here we reclassify CSPN IRAS 15127-5811 as a blue supergiant with a surrounding bi-polar nebula. Nevertheless, we collected all available information on proposed member
stars for both these clusters. We conclude that neither claimed cluster is real. Our results shed considerable doubt on the veracity of many newly identified OCs that have modest numbers of
stellar members.
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All authors Andreas Ritter, Quentin A. Parker, Xizhe Xie, Xingyi Guo
Materials Science
A Thermodynamic-Limit Pinning Criterion for Two-Dimensional Structural Superlubricity
Li Wang and Yunjie Ye
Incommensurability and elastic reconstruction do not by themselves define a structurally superlubric phase. We define fully sliding and pinned zero-temperature phases by $\limsup_{A\to\infty}\tau_{\rm dep}^{\max}(A)=0$ and $\liminf_{A\to\infty}\tau_{\rm dep}^{\min}(A)>0$, respectively; $\Lambda_n=|V_n|G_{n,i}[D_{\rm rel}^{-1}(\mathbf q_n)]_{ij}G_{n,j}$ measures only reconstruction susceptibility. Translational covariance then proves that a clean, smooth, infinite moiré continuum can reconstruct without acquiring a bulk sliding barrier. We restore atomic sampling in a two-dimensional discrete model of
graphene/hBN and test both a
diffusion quantum Monte Carlo first-
star potential and a 15-harmonic Leven potential across three rational approximants and five directions. No physical-coupling
equilibrium or metastable barrier is resolved. The Leven spectrum raises the largest tested $\Lambda$ from $0.142$ to $0.212$, while artificial scaling through $\Lambda=1$ reaches uncontrolled strain before a size-independent threshold appears. The tested zero-temperature in-plane models are therefore consistent with an elastically relaxed sliding regime; $\Lambda=1$ is a reconstruction scale, not a static phase criterion.
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Solar and Stellar Astrophysics
Solar differential rotation driven by baroclinic forcing
L. S. Menicucci, G. Guerrero, M. Dikpati et al. (+3 more)
A combination of recent observations and numerical simulations has called into question whether Sun's interior is characterized by strong turbulent convection, a problem known as convective conundrum. In light of a possible absence of vigorous convective motions, we examine whether the Sun's differential rotation, previously assumed to be tightly coupled to Reynolds stresses, may instead be sustained by the presence of a background latitudinal
entropy gradient in thermal wind balance. By performing global hydrodynamical simulations of a rotating spherical shell representing the bulk of the
solar convection zone, we demonstrate that
solar-like differential rotation can be generated under a variety of thermal stratifications. This work proposes an alternative scenario for the origin of
solar differential rotation that accommodates the previously reported discrepancies.
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All authors L. S. Menicucci, G. Guerrero, M. Dikpati, R. Hester, J. Zhang, P. K. Smolarkiewicz
Quantum Physics
Robust logical Bell nonlocality based on quantum error correction codes
Qi Zhang, Jia-Wei Ying, Cheng Liu et al. (+2 more)
Quantum nonlocality based on the violation of Bell-like inequalities constitutes a fundamental feature of
quantum physics and drives the development of device-independent (DI)
quantum information technologies. Existing studies of Bell nonlocality have mainly focused on physical
qubit systems, where the observed nonlocal correlations are directly encoded in physical degrees of freedom. The decoherence sensitivity of Bell nonlocality largely limits the performance and security of its DI applications. Here, we investigate the robust logical Bell nonlocality based on
quantum error correction codes. We construct the general logical Bell inequality in the stabilizer coding subspace and prove its violation indicates the global nonlocal feature of the logical system. Then, we indicate that the logical Bell nonlocality is robust against decoherence. Comparing with the physical
qubit system, the fidelity thresholds for the logical Bell inequality violation based on the [[3,1,1]] and [[7,1,1]] repetition codes under the bit-flip error model can be reduced from 82.8% to 73.10% and 66.35%, increasing DI QKD's bit-flip noise threshold from 10.64% to 14.42% and 23.36%, respectively. Such stabilizer-based framework can be also used to characterize the multipartite logical Bell nonlocality in principle. Finally, a logical Bell test implementation
circuit based on the [[3,1,1]] repetition code is presented. This work provides a feasible avenue for unlocking robust Bell nonlocality in scalable logical
quantum systems and facilitates its applications in future scalable
quantum network.
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All authors Qi Zhang, Jia-Wei Ying, Cheng Liu, Lan Zhou, Yu-Bo Sheng
Solar and Stellar Astrophysics
Exploring the Small-scale Magnetic Fields in the Atmosphere of HD 49385 by Asteroseismic Analysis
Yuetong Wang, Yaguang Li, Yan Li et al. (+2 more)
Recent asteroseismic studies have shown convincing evidences that
magnetic fields may exist in the interior of some pulsating red
giants. Inspired by this breakthrough, we explored the effect of small-scale
magnetic fields on the p-mode oscillations in an evolved
star, HD 49385. {\bf We incorporate a modified Eddington $T$-$\tau$ equation that phenomenologically mimics the effect of the
magnetic fields in the atmosphere of HD 49385,} and calculate the frequencies of p-modes with $l=0$, 1, and 2. By comparing the calculated frequencies with the observed ones, we select two best-fit models with either GS98 or A09 chemical composition. Our best-fit models not only fit satisfactorily the observed frequencies, but also well reproduce some spectroscopically observed
stellar parameters such as effective temperature and log\,$g$. Based on the two best-fit models, we have estimated that the small-scale
magnetic fields possess a strength of approximately 80\,G and spread concentratively at approximately a height of 1850 km in the atmosphere. By selecting the best-fit models with special requirement on the avoided-crossing mode, we have confirmed that the frequency of the avoided-crossing mode is tightly related to the helium core of the
star, and determined the size of the helium core as 0.117${\rm M}_\odot$ in mass and 0.078${\rm R}_\odot$ in radius. Based on the improvements of previous two sides, we can accurately determine the mass of HD 49385 to be $1.25\pm 0.02\,{\rm M}_\odot$ with an age of 4.1\,Gyr for GS98 composition and 4.5\,Gyr for A09 composition.
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All authors Yuetong Wang, Yaguang Li, Yan Li, Guifang Lin, Tao Wu
Solar and Stellar Astrophysics
Asteroseismic Analysis of a Red Giant KIC 9145955 by Including the Small-scale Magnetic Fields in the Atmosphere
Yuetong Wang, Guifang Lin, Yan Li et al. (+2 more)
Recent convincing evidence is found within asteroseismology that suggests the
magnetic fields exist in three red
giants. Research on small-scale
magnetic fields in the Sun and HD 49385 has shown that they have a certain corrective effect on the systematic discrepancies between observed and theoretical frequencies. Here we apply a similar method applied for the Sun to a red
giant, KIC 9145955, to explore the impact of small-scale
magnetic fields in the photosphere on its frequencies. We find that the calculated frequencies of our best-fit model, which simulates the effect of the
magnetic fields by artificially modifying the Eddington $T-\tau$ relation, perfectly match those of the observed l = 0, 1, and 2 modes, indicating the existence of small-scale
magnetic fields with an upper strength limit of 65 G and concentrating at a height 13,100 km in the photosphere. Based on the best-fit model, we revise the
stellar parameters of KIC 9145955 as: $M = 1.23\pm0.04\,M_\odot$, $R = 5.57\pm0.06\,R_\odot$, $L = 19.85\pm0.5\,L_\odot$, $Age = 3.83\pm0.5$\,Gyr, $M_{\rm He} = 0.2108\pm0.0005M_\odot$, and $R_{\rm He} = 0.0306\pm0.0001R_\odot$.
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All authors Yuetong Wang, Guifang Lin, Yan Li, Tao Wu, Yaguang Li
Astrophysics of Galaxies
When Galaxies Refuel: Evolution of the Perturbed Spiral Galaxy NGC1385
Xiaoyu Kang, Eva Sextl, Rolf-Peter Kudritzki et al. (+5 more)
The spiral
galaxy NGC 1385 is characterized by a vigorous and protracted history of
star formation, particularly in its central regions, leading to a current
star formation rate that surpasses those of comparable systems. We analyze the
evolution history of the
galaxy using spatially resolved optical and submillimeter spectroscopy obtained from the PHANGS survey combined with WALLABY
radio survey data. We construct radial distributions of
star formation rate and the interstellar medium (ISM) neutral and molecular gas mass surface densities and measure the
metallicity distribution of the
stellar populations using a refined full-spectral fitting population synthesis method together with a determination of ISM oxygen abundances using H\,II region emission lines. The
metallicities of the young
stars and the ISM are similar and show an almost flat distribution. This is crucially different from previous work which had found a positive gradient for the average
metallicities of the
stars. We fit a chemical
evolution model (incorporating gas infall,
outflow, and radial inflow) to the observed data of NGC\,1385. Based on this fit, the
evolution of NGC\,1385 is characterized by the typical inside-out disk formation of spiral
galaxies – even though our model does not assume an a priori shorter gas infall timescale for the inner disk than for the outer disk. However, the
galaxy has experienced sustained
star formation over gigayear timescales with a
star formation efficiency a factor of two higher than normal. This explains the high
metallicity of the young
stars of 0.15 to 0.2\,dex higher than
solar and the flat distribution of
metallicity across the disk. The model predictions for the
metallicities of the
stars align well with the observed values, supporting the robustness of both our refined spectral fitting analysis and the inferred evolutionary scenario.
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All authors Xiaoyu Kang, Eva Sextl, Rolf-Peter Kudritzki, Hassen M. Yesuf, Fenghui Zhang, Ruixiang Chang, Xiejin Li, Yunkun Han
Quantum Physics
Structured-light-mediated hybrid entanglement between photon polarization and electronic orbital angular momentum
Hiroaki Saito and Nobuhiko Yokoshi
We propose a minimal
quantum-optical scheme for generating hybrid
entanglement between
photon polarization and electronic orbital angular momentum in a
semiconductor quantum disk. A
spin–orbit structured two-
photon state excites two channels in the same disk: a radiatively recombining zero-orbital-angular-momentum channel and a finite-orbital-angular-momentum channel that stores the electronic orbital
qubit. An effective coherent mapping prepares a selected two-excitation state, followed by emission of a
photon whose polarization is entangled with the residual electronic orbital state. A master-equation analysis shows that the heralded state conditioned on single-
photon occupation of the selected output mode approaches the target entangled state in the ideal coherent limit. We also discuss orbital relaxation and perturbative validity conditions for branch-dependent Coulomb shifts, orbital-angular-momentum mixing, and finite-orbital-angular-momentum radiative leakage. This proof-of-principle effective model suggests a route toward structured-light-mediated
photon–electron hybrid
entanglement in
semiconductor nanostructures.
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High Energy Physics (Theory)
Point-Like Charges and Dirichlet Boundary Conditions in a Nonlocal Scalar Field Theory
L.H.C. Borges, C. Filgueiras, F.A. Barone et al. (+1 more)
In this paper, we investigate novel classical non-local effects in scalar field theory arising from the presence of external sources and a material boundary. Specifically, we consider a model in which the standard Klein-Gordon field theory is modified by a non-local term. First, we analyze the interaction between stationary field sources modeled as point-like scalar charges. In specific configurations, the resulting interparticle potential reduces to the Cornell form. Then, we examine the model in the presence of a Dirichlet plane, computing both the scalar field propagator and the interaction force between the Dirichlet plane and a point-like scalar charge. Additionally, we demonstrate the failure of the image method in this non-local context and compare our results with those obtained in non-local electrodynamics and in the standard Klein-Gordon field theory.
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All authors L.H.C. Borges, C. Filgueiras, F.A. Barone, A.A. Nogueira
Mesoscale and Nanoscale Physics
Majorana interface states in anisotropic and tilted Dirac and Weyl systems
Abraham Kaleb Plascencia Pérez Páez and Alireza Qaiumzadeh
Anisotropy and cone tilt change how Majorana states propagate along an interface and decay away from it. We derive a two-dimensional Majorana surface
Hamiltonian from a fully gapped three-dimensional
superconductor, with the surface mass generated by the relative phase between triplet and singlet pairing. For a mass domain wall on this surface, we obtain the wave function, propagation velocity, and localization length of the resulting one-dimensional channel for a general invertible velocity tensor and an arbitrary wall orientation. The product of propagation speed and localization length is independent of wall orientation in the anisotropic model. For a smooth closed channel without a
vortex, the propagation time around the wall determines the lowest excitation energy. For a tilted surface cone, the normal and parallel components of tilt affect confinement and propagation differently. We also solve a separate three-dimensional Weyl model with uniform singlet pairing and a reversing exchange field. In the regime supporting interface states, its bulk remains gapless. At zero chemical potential, two states confined perpendicular to the wall and propagating within its plane have the same dispersion over a finite momentum interval. Numerical diagonalization confirms the analytical energies and wave functions.
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High Energy Astrophysical Phenomena
No Surviving Companion to the Galactic SN 1181: Evidence for a Double-Degenerate Channel for Type Iax Supernovae
Kohki Uno, Daichi Tsuna, Daichi Hiramatsu et al. (+2 more)
Type Iax
supernovae (SNe Iax) are the recently-established, yet peculiar subclass of thermonuclear
supernovae, whose progenitor systems and explosion mechanisms remain debated. A leading scenario is a single-degenerate channel, in which a white
dwarf accreting from a He-
star companion undergoes a pure deflagration, leaving both a bound remnant and surviving companion. The
Galactic SN 1181, whose distinctive properties are consistent with an SN Iax involving a weak explosion and bound white
dwarf remnant, offers a unique opportunity to test this scenario. Here, we perform a deep search for a surviving He-
star companion, a hallmark of the single-degenerate He-donor channel, within $30^{\prime\prime}$ ($\sim 0.3$ pc) of the remnant using archival
Gaia and Pan-STARRS1 data. The parallaxes and proper motions exclude all
Gaia sources, while the spectral energy distributions of the remaining Pan-STARRS1 sources are inconsistent with both the He-
star spectral templates and known hot-subdwarf population. Binary
evolution calculations predict a minimum mass of a companion with an absolute $g$-band magnitude of $M_{g} \lesssim 6.5$ mag, much brighter than the Pan-STARRS1 detection limit of $M_{g} > 8$ mag. Our non-detection rules out He-
star and luminous hydrogen-rich companions for SN 1181, favoring a double-degenerate channel (i.e., a white
dwarf merger). Adding to the luminous He-
star companion identified in the pre-explosion imaging of SN 2012Z, our results provide direct evidence for multiple progenitor channels leading to SNe Iax.
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All authors Kohki Uno, Daichi Tsuna, Daichi Hiramatsu, Tomoya Kinugawa, Takatoshi Ko
Quantum Physics
Exact Closed-Form Quantum Correlations of Maximally Entangled Qudit States under Arbitrary Non-Markovian Pure Dephasing
Ahmad Akhound
We study the time
evolution of
entanglement and
quantum discord for a pair of maximally entangled qudits of arbitrary dimension $d$ under non-Markovian pure dephasing, using the exact solution of the independent
boson model. Because this solution requires no Born–Markov, Lindblad, or rotating-wave approximation, every result reported here follows directly from the exact dynamics. Exploiting the Toeplitz structure of the resulting density
matrix, we obtain a closed-form expression for the negativity as a finite sum, valid for arbitrary dimension and
evolution time, together with a corresponding closed-form expression for the
quantum discord. For the family of dephased maximally entangled states considered here, we prove that a computational-basis measurement is globally optimal over the entire POVM space, thereby eliminating the numerical optimization otherwise required for evaluating the
quantum discord. We further show that both quantities saturate, as the dimension grows, to a dimension-independent limiting value, with a convergence rate of exactly $1/d$. For negativity, this scaling law is established through a rigorous
theorem, including a Gaussian-type error bound of order $e^{-\alpha d^2}$, and is confirmed across six independent parameter regimes for two distinct classes of spectral density, Lorentzian and Ohmic; for discord, the same leading-order behavior is found numerically across the six Lorentzian regimes. The analytical results are validated by independent numerical approaches, including reconstruction from the underlying definitions, arbitrary-precision arithmetic, and a complementary pseudomode cross-check.
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Materials Science
Analytical Retrieval of Material Parameters in Monolayer Transition-Metal Dichalcogenides Based on a Solvable Exciton Model
Duy-Nhat Ly, Thanh-Son Nguyen, Ngoc-Tram D. Hoang et al. (+1 more)
We develop an analytical procedure to retrieve fundamental material parameters of monolayer transition-metal dichalcogenides from optical and magneto-optical
exciton spectra, based on the solvable modified Kratzer model. The proposed
retrieval procedure naturally consists of two complementary stages. In the first stage, explicit inversion formulas determine the quasiparticle bandgap, effective screening parameter, and energy scaling factor directly from the experimentally measured energies of the three lowest excitonic states, from which the screening length is subsequently obtained. In the second stage, an analytical expression for the
magnetic-field dependence of the
exciton energies independently yields the reduced
exciton mass, from which the surrounding dielectric constant is then calculated. Once the complete set of material parameters has been retrieved, the framework analytically predicts the diamagnetic coefficients,
exciton radii, and complete magnetoexciton spectra without introducing additional fitting parameters or
matrix diagonalization. The method is applied to a broad range of experimental samples for WSe$_2$, WS$_2$, MoS$_2$, MoSe$_2$, and MoTe$_2$ monolayers embedded in different dielectric environments. The retrieved material parameters are in good agreement with independent experimental measurements and previous Rytova–Keldysh (RK) calculations, while the predicted excitonic properties accurately reproduce available magneto-optical observations. The proposed analytical theory provides an efficient, physically transparent alternative to conventional numerical fitting procedures and offers an effective tool for the rapid characterization of two-dimensional
semiconductors via excitonic spectroscopy.
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All authors Duy-Nhat Ly, Thanh-Son Nguyen, Ngoc-Tram D. Hoang, Van-Hoang Le
Strongly Correlated Electrons
Twisting-operator approach to identifying gaplessness in SU($N$) fermionic systems
Hao Cheng, Hang Su and Yuan Yao
We propose a general necessary condition for a spinful
fermion chain with SU(2)
spin-rotation
symmetry to be gapped. Specifically, we prove that the expectation value of a properly defined fermionic twisting operator asymptotically approaches unity in any gapped phase with finite ground-state degeneracy, with finite-size corrections bounded by $\mathscr{O}(1/L)$. Consequently, a non-unity value in the thermodynamic limit provides a sufficient criterion for identifying gapless
fermion chains. We confirm this criterion using the $s$-wave Bardeen-Cooper-Schrieffer (BCS)
Hamiltonian and determinant
quantum Monte Carlo (DQMC) simulations of interacting Hubbard models. We further extend the twisting-operator approach to SU($N$)-symmetric fermionic systems, where the gapped ground-state sector must be SU($N$)-singlet and $\langle \hat{\mathcal{U}}^M\rangle=1+\mathscr{O}(1/L)$ by a fermionic twisting operator $\hat{\mathcal{U}}$ with a suitably chosen integer $M$.
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Physics and Society
From risk to flourishing: Seeds for responding to a complex world
Ryan M. McGranaghan, Elisabeth H. Krueger, Alexandre Dunant et al. (+6 more)
Complex risk arises when interacting hazards, infrastructures, ecological systems, institutions, and human behaviors produce nonlinear impacts that cannot be inferred from any component in isolation. We call the study of these dynamics complex risk science. Flourishing is the actualization of all beings toward their good–individually and collectively–answering the question of `how do we live well with and for each other?'. In science as in society, the tendency to reduce, segregate, specialize, and settle has precluded embracing the concept of flourishing as a guiding principle. We describe how complex risk science reframes risk science research so that it can promote the flourishing of socio-ecological-technological systems, and explore how its practice may point society toward a more flourishing future. Our exploration mirrors the unsettled and searching nature of flourishing: examine ideologies traditionally believed to be rigidly in opposition and consider what emerges in the space(s) and conversation between them. We call this a dialectical approach: not a means of resolving contradiction, but a practice of sustaining it, so that systems, and our understanding of them, remain capable of reframing as conditions change. Within this dialectical paradigm, we revisit longstanding tensions in risk science: physical|social, determinism|uncertainty, and contextuality|generality. Examining the conversation among these tensions reveals five seeds that are dispositions for practicing complex risk science: interdependence, responsivity, participation, pluralism, and ongoingness. They can support any scientific endeavor to embrace complexity and promote flourishing. Practicing these seeds at scale will depend on institutional reform: creating collectives toward complex risk science, supporting them with skillfully governed commons, and centering care in our research and evaluation.
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All authors Ryan M. McGranaghan, Elisabeth H. Krueger, Alexandre Dunant, Guillaume Falmagne, Lynee L. Turek-Hankins, Sara M. Constantino, Raissa D'Souza, Elke U. Weber, Graydon W. Manzke
Chemical Physics
Nuclear Quantum Effects as a Denoising Problem
Weizhou Wang, Jonathan Weare and Aaron R. Dinner
Nuclear quantum effects are rigorously captured by imaginary-time path integrals, which map the
quantum Boltzmann distribution onto a ring
polymer of classical replicas. Yet the
nuclear masses, the coupling to the environment, and the boundary conditions of the path remain hard-wired in the simulation or the trained model, even though this
quantum context enters the path measure only through a quadratic action known in closed form. Here we show that a denoiser trained on classical Boltzmann statistics alone, composed at sampling time with an analytic Gaussian component carrying the entire
quantum context, yields the
quantum Boltzmann distribution of the
nuclei. Such a composition exists and is exact whenever the training noise does not exceed the intrinsic
quantum uncertainty of the target ensemble, and it is invariant across all
quantum contexts admitted by this bound. We show exact transfer across temperature, isotopic mass, dissipation strength, and the boundary conditions of the path in theory and in numerical experiments, without retraining. The last yields the end-to-end displacement and momentum distributions of a tagged
nucleus from open imaginary-time paths. The same invariance extends in principle to the permuted boundary conditions of bosonic exchange, with the identical denoiser. In this view, the noise of generative modeling and the
quantum fluctuations of the
nuclei are two faces of the same quadratic structure.
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Materials Science
Synergistic Interface Stability and High Room-Temperature Ionic Conductivity for Wide-Temperature All-Solid-State Batteries Based on Li6+xSixSb1-xS5I Electrolytes
Liang Ming, Qizhiran Sun, Guanping Xu et al. (+7 more)
Solid-state lithium-ion batteries (LIBs) are increasingly recognized for their exceptional energy density and safety. However, their widespread adoption is challenged by persistent issues such as thermal and electrochemical instability, dendrite formation, and limited compatibility with high-voltage cathodes. Sulfide-based solid electrolytes (SEs), particularly iodide argyrodites, offer outstanding ionic conductivity and stability; however, their practical application is constrained by the formation of space-charge layers, slow ion transport, and susceptibility to dendrite penetration. To address these challenges, we synthesized a novel Li6.6Si0.6Sb0.4S5I argyrodite electrolyte via ball milling and heat treatment, achieving a remarkable room-temperature ionic conductivity of 9.9 mS cm^-1. The electrolyte was integrated with a LiNbO3-coated LiNi0.7Co0.1Mn0.2O2 cathode to form an all-solid-state battery, which demonstrated an initial discharge capacity of 171.2 mAh g^-1, retained 84.2% of its capacity after 200 cycles at 0.5C, and maintained stable cycling across a broad temperature range from -20 degrees C to 60 degrees C. Our study shows that tailored electrolyte composition and a composite cathode configuration significantly enhance cycling stability and improve interfacial protection. These findings highlight the potential of Si-doped antimony-type iodide argyrodites for next-generation high-performance all-solid-state batteries, offering durable operation under diverse thermal conditions.
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All authors Liang Ming, Qizhiran Sun, Guanping Xu, Muqing Su, Enyan Zhao, Wenzhe Gu, Weng-Fu Io, Kwun Nam Hui, Chuang Yu, Hai-Feng Li
Materials Science
Raman spectroscopy of van der Waals topological magnet GdGaI
Nan Jiang, Yijin Zhang, Yujie Xia et al. (+9 more)
We report polarization-resolved Raman spectroscopy of a van der Waals compound GdGaI that is a candidate for excitonic
insulators. By combining the
symmetry analysis with density functional theory calculations, we identify six Raman-active
phonons. The spectra exhibit only the expected anharmonic hardening down to 4 K: no additional peaks, no soft modes, and no signatures of zone folding are observed. This result indicates that any
lattice distortion is below our experimental sensitivity, supporting an electronically driven origin for the band reconstruction reported by angle-resolved photoemission spectroscopy rather than an electron-
phonon-driven mechanism. Moreover, we observe a pronounced circular dichroism of the $A_{1g}$ modes under an out-of-plane
magnetic field. Based on
symmetry considerations, we attribute this dichroic response to
chiral $A_{1g}$
phonons with opposite angular momenta generated by
spin-
phonon coupling in the time-reversal-broken state. The temperature
evolution of the degree of circular polarization further suggests that circularly polarized Raman spectroscopy detects the emergence of short-range
antiferromagnetic correlations. Our results highlight GdGaI as a promising platform in which excitonic order, magnetism, and circularly polarized
phonons can be intertwined, and demonstrate that circular-polarization Raman provides a sensitive probe of
spin-
phonon coupling in excitonic systems.
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All authors Nan Jiang, Yijin Zhang, Yujie Xia, Tomo Higashihara, Ryutaro Okuma, Jun-ichi Yamaura, Yoshinori Okada, Kenji Watanabe, Takashi Taniguchi, Tiantian Zhang, Tomoki Machida, Yasuhiro Niimi
General Relativity and Quantum Cosmology
On the geometrical and dynamical distinction between Unimodular and General Relativistic wormholes
Marco Bosquez, Erick Pastén, Mauricio Cataldo et al. (+1 more)
We characterize traversable wormholes in Unimodular
Gravity (UG) and investigate what distinguishes them from their General Relativistic (GR) counterparts. For a class of static and spherically symmetric solutions, we analyze their
embedding and timelike geodesics, showing that the geodesic structure is entirely determined by the metric and is therefore identical in both theories. To identify the physical origin of their differences, we compare the source sectors required to sustain the same wormhole geometry. We find that preserving a fixed UG geometry while imposing energy-momentum conservation requires restricting the equation of state, whereas relaxing this condition introduces an effective inhomogeneous
vacuum contribution. We further show that the degree of exoticity is preserved even when energy-momentum is not conserved, while departures from the GR sector are encoded in an effective inhomogeneous
vacuum structure whose asymptotic behavior resembles that of a cosmological constant. Our results reinforce that UG is geometrically equivalent to GR, while its distinctive features emerge in the dynamical interpretation of the source sector. More generally, our analysis illustrates that different gravitational theories may give rise to identical spacetime geometries while requiring different sources to sustain them.
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All authors Marco Bosquez, Erick Pastén, Mauricio Cataldo, Norman Cruz
Materials Science
Nitrospinics as a platform from orbital-torque memory to artificial intelligence
Prabhat Kumar, Gaurav Kumar Shukla, Yoshio Miura et al. (+1 more)
The exploration of energy-efficient and functional spintronics has attracted considerable
attention. Orbital transport has opened new pathways for current-induced torque generation beyond the conventional
spin transport based on the
spin Hall effect. In addition, artificial intelligence computing has been demonstrated using spintronic devices. Further progress of these devices can be anticipated through the development of unique and functional materials beyond the existing heavy metals and topological systems with strong
spin-orbit coupling. The nitride materials exhibit unique chemical,
magnetic, and structural versatility, including antiferromagnetism, high thermal stability, and compatibility with diverse device architectures. Here, we propose Nitrospinics as a conceptual and functional framework that exploits nitride materials for applications ranging from orbital-torque-based spintronic devices to artificial intelligence hardware. Using Cr2N, a two-dimensional nitride MXene with an atomic layered structure, as a prototype system, we discuss how nitrogen contributes to the structural stability, the orbital torque generation, and the interfacial orbital and
spin conversion. We further outline key challenges and opportunities toward establishing nitride-based materials for next-generation computing technologies.
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All authors Prabhat Kumar, Gaurav Kumar Shukla, Yoshio Miura, Shinji Isogami
Optics
An integrated super resolution THz 3D imaging system based on a linear nonlocal achromatic freeform Bessel beam lens and high power oscillator radiator array
Jin Chen, Liang Gao, Hao Guo et al. (+5 more)
High performance terahertz (THz) 3D imaging is critical for non-destructive evaluation. However, conventional architectures are fundamentally limited by severe chromatic aberrations, modest spatial resolution, restricted depths of focus (DOF), and the bulky nature of commercial transceivers. While metasurfaces offer a compact alternative, achieving broadband achromatic super-resolution with an extended DOF remains a formidable challenge. Here, we present a highly integrated 3D THz imaging platform that synergizes a 3D printed nonlocal freeform Bessel-beam lens with a high power, 65nm CMOS oscillator radiator array. Harnessing nonlocal interactions within the lens, we generate an achromatic super resolution Bessel beam (0.3 to 1 THz) with a subdiffraction full width at half maximum (FWHM) of 0.65{\lambda} and a robust 4.7-mm DOF. Crucially, the system overcomes conventional sidelobe limitations, enabling high-fidelity 2D imaging of intricate sub-millimeter targets (e.g., USAF 1951 charts and QR codes) alongside robust 3D volumetric imaging through highly scattering media, such as printed
circuit boards. By converging standard CMOS technology with additive manufacturing, this work establishes a versatile, cost-effective paradigm for next-generation integrated THz photonics
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All authors Jin Chen, Liang Gao, Hao Guo, Zhi Chao Chen, Kang Jie Lin, Kam Man Shum, Ka Fai Chan, Chi Hou Chan