Miracle-dz/UniFAR-FTUs huggingface dataset:
Multipartite entanglement measures and quantum criticality from matrix and tensor product states

We compute the multipartite entanglement measures such as the global entanglement of various one- and two-dimensional quantum systems to probe the quantum criticality based on the matrix and tensor product states (MPSs and TPSs). We use the infinite time-evolving block decimation (iTEBD) method to find the ground states numerically in the form of MPSs and TPSs, and then evaluate their entanglement measures by the method of tensor renormalization group (TRG). We find that these entanglement measures can characterize the quantum phase transitions by their derivative discontinuity right at the critical points in all models considered here. We also comment on the scaling behaviors of the entanglement measures by the ideas of quantum-state renormalization group transformations.
Donaldson-Thomas theory for categories of homological dimension one with potential

The aim of the paper is twofold. Firstly, we give an axiomatic presentation of Donaldson-Thomas theory for categories of homological dimension at most one with potential. In particular, we provide rigorous proofs of all standard results concerning the integration map, wall-crossing, PT-DT correspondence, etc. following Kontsevich and Soibelman. We also show the equivalence of their approach and the one given by Joyce and Song. Secondly, we relate Donaldson-Thomas functions for such a category with arbitrary potential to those with zero potential under some mild conditions. As a result of this, we obtain a geometric interpretation of Donaldson-Thomas functions in all known realizations, i.e. mixed Hodge modules, perverse sheaves and constructible functions.
The rise and fall of stellar across the peak of cosmic star formation history: Effects of mergers versus diffuse stellar mass acquisition

Building galaxy merger trees from a state-of-the-art cosmological hydrodynamical simulation, Horizon-AGN, we perform a statistical study of how mergers and diffuse stellar mass acquisition processes drive galaxy morphologic properties above z > 1. By diffuse mass acquisition here, we mean both accretion of stars by unresolved mergers (relative stellar mass growth smaller than 4.5 per cent) as well as in situ star formation when no resolved mergers are detected along the main progenitor branch of a galaxy. We investigate how stellar densities, galaxy sizes and galaxy morphologies (defined via shape parameters derived from the inertia tensor of the stellar density) depend on mergers of different mass ratios. We investigate how stellar densities, effective radii and shape parameters derived from the inertia tensor depend on mergers of different mass ratios. We find strong evidence that diffuse stellar accretion and in situ formation tend to flatten small galaxies over cosmic time, leading to the formation of discs. On the other hand, mergers, and not only the major ones, exhibit a propensity to puff up and destroy stellar discs, confirming the origin of elliptical galaxies. We confirm that mergers grow galaxy sizes more efficiently than diffuse processes ($$r_{0.5}\propto M_{\rm s}^{0.85}$$ and $$r_{0.5}\propto M_{\rm s}^{0.1}$$ on average, respectively) and we also find that elliptical galaxies are more susceptible to grow in size through mergers than disc galaxies with a size–mass evolution $$r_{0.5}\propto M_{\rm s}^{1.2}$$ instead of $$r_{0.5}\propto M_{\rm s}^{-0.5}-M^{0.5}$$ for discs depending on the merger mass ratio. The gas content drives the size–mass evolution due to merger with a faster size growth for gas-poor galaxies $$r_{0.5}\propto M_{\rm s}^{2}$$ than for gas-rich galaxies r_0.5 ∝ M_s.
Black hole mass estimate for a sample of radio-loud narrow-line Seyfert 1 galaxies

We discuss the relationship between a standard Shakura & Sunyaev (1973) accretion disk model and the Big Blue Bump (BBB) observed in Type 1 AGN, and propose a new method to estimate black hole masses. We apply this method to a sample of 23 radio-loud narrow-line Seyfert 1 (RL-NLS1) galaxies, using data from WISE (Wide-field Infrared Survey Explorer), SDSS (Sloan Digital Sky Survey) and GALEX. Our black hole mass estimates are at least a factor $\sim$6 above previous results based on single epoch virial methods, while the Eddington ratios are correspondingly lower. Hence, the black hole masses of RL-NLS1 galaxies are typically above $10^8 M_{\sun}$, in agreement with the typical black hole mass of blazars.
An alternative proof of lower bounds for the first eigenvalue on manifolds

Recently, Andrews and Clutterbuck [1] gave a new proof of the optimal lower eigenvalue bound on manifolds via modulus of continuity for solutions of the heat equation. In this short note, we give an alternative proof of Theorem 2 in [1]. More precisely, following Ni's method (Section 6 of [5]), we give an elliptic proof of this theorem.
2MASS TWO-COLOR INTERSTELLAR REDDENING LINE IN THE DIRECTION OF THE NORTH AMERICA AND PELICAN NEBULAE AND THE CYG OB2 ASSOCIATION

passbands which is useful for a variety of investigations of the Galaxy. Thesystem has been successfully used for study of star-forming regions and searchfor young stellar objects (YSOs), for investigation of the interstellar extinction indust/molecular clouds, large-scale distribution of interstellar dust, the interstellarreddening law in the infrared, spectral energy distributions, etc.Recently, the interstellar reddening law in the infrared wavelengths was studiedby Fitzpatrick & Massa (2005, 2007), Indebetouw et al. (2005) and Flaherty etal. (2007) applying the 2MASS data alone or joining them with the Spitzer resultsat longer wavelengths. In some papers regional values of the color excess ratioE
HEAD-ON COLLISIONS OF WHITE DWARFS IN TRIPLE SYSTEMS COULD EXPLAIN TYPE Ia SUPERNOVAE

Type Ia supernovae (SNe Ia), thermonuclear explosions of carbon–oxygen white dwarfs (CO-WDs), are currently the best cosmological “standard candles,” but the triggering mechanism of the explosion is unknown. It was recently shown that the rate of head-on collisions of typical field CO-WDs in triple systems may be comparable to the SNe Ia rate. Here we provide evidence supporting a scenario in which the majority of SNe Ia are the result of such head-on collisions of CO-WDs. In this case, the nuclear detonation is due to a well understood shock ignition, devoid of commonly introduced free parameters such as the deflagration velocity or transition to detonation criteria. By using two-dimensional hydrodynamical simulations with a fully resolved ignition process, we show that zero-impact-parameter collisions of typical CO-WDs with masses 0.5–1 M☉ result in explosions that synthesize 56Ni masses in the range of ∼0.1–1 M☉, spanning the wide distribution of yields observed for the majority of SNe Ia. All collision models yield the same late-time (≳ 60 days since explosion) bolometric light curve when normalized by 56Ni masses (to better than 30%), in agreement with observations. The calculated widths of the 56Ni-mass-weighted line-of-sight velocity distributions are correlated with the calculated 56Ni yield, agreeing with the observed correlation. The strong correlation, shown here for the first time, between 56Ni yield and total mass of the colliding CO-WDs (insensitive to their mass ratio), is suggestive as the source for the continuous distribution of observed SN Ia features, possibly including the Philips relation.
Prediction and optimization of airfoil aerodynamic performance using deep neural network coupled Bayesian method

In this paper, we proposed an innovative Bayesian optimization (BO) coupled with deep learning for rapid airfoil shape optimization to maximize aerodynamic performance of airfoils. The proposed aerodynamic coefficient prediction model (ACPM) consists of a convolutional path and a fully connected path, which enables the reconstruction of the end-to-end mapping between the Hicks–Henne (H–H) parameterized geometry and the aerodynamic coefficients of an airfoil. The computational fluid dynamics (CFD) model is first validated with the data in the literature, and the numerically simulated lift and drag coefficients were set as the ground truth to guide the model training and validate the network model based ACPM. The average accuracy of lift and drag coefficient predictions are both about 99%, and the determination coefficient R2 are more than 0.9970 and 0.9539, respectively. Coupled with the proposed ACPM, instead of the conventional expensive CFD simulator, the Bayesian method improved the ratio of lift and drag coefficients by more than 43%, where the optimized shape parameters of the airfoil coincide well with the results by the CFD. Furthermore, the whole optimization time is less than 2 min, two orders faster than the traditional BO-CFD framework. The obtained results demonstrate the great potential of the BO-ACPM framework in fast and accurate airfoil shape optimization and design.
SPIRAL DENSITY WAVES IN M81. II. HYDRODYNAMIC SIMULATIONS OF THE GAS RESPONSE TO STELLAR SPIRAL DENSITY WAVES

The gas response to the underlying stellar spirals is explored for M81 using unmagnetized hydrodynamic simulations. Constrained within the uncertainty of observations, 18 simulations are carried out to study the effects of self-gravity and to cover the parameter space comprising three different sound speeds and three different arm strengths. The results are confronted with the data observed at wavelengths of 8 μm and 21 cm. In the outer disk, the ring-like structure observed in the 8 μm image is consistent with the response of cold neutral medium with an effective sound speed 7 km s−1. For the inner disk, the presence of spiral shocks can be understood as a result of 4:1 resonances associated with the warm neutral medium with an effective sound speed 19 km s−1. Simulations with a single effective sound speed alone cannot simultaneously explain the structures in the outer and inner disks. Instead this justifies the coexistence of cold and warm neutral media in M81. The anomalously high streaming motions observed in the northeast arm and the outward shifted turning points in the iso-velocity contours seen along the southwest arm are interpreted as signatures of interactions with companion galaxies. The level of simulated streaming motions narrows down the uncertainty of the observed arm strength toward larger amplitudes.
The Galactic plane at faint X-ray fluxes – I. Properties and characteristics of the X-ray source population

We investigate the serendipitous X-ray source population revealed in XMM–Newton observations targeted in the Galactic plane within the region 315 ◦ 10 32 erg s −1 , whereas some will be extragalactic interlopers. A high fraction (90 per cent) of the soft sources have potential near-infrared (NIR) (Two-Micron All-Sky Survey and/or United Kingdom Infrared Deep Sky Survey) counterparts inside their error circles, consistent with the dominant soft-X-ray-source population being relatively nearby coronally-active stars. These stellar counterparts are generally brighter than J = 16, a brightness cut-off which corresponds to the saturation of the X-ray coronal emission at LX = 10 −3 Lbol. In contrast, the success rate in finding likely IR counterparts to the hard X-ray sample is no more than ≈15 per cent down to J = 16 and ≈25 per cent down to J = 20, set against a rapidly rising chance coincidence rate. The make-up of the hard-X-ray-source population, in terms of the known classes of accreting and non-accreting systems, remains uncertain.
The critical radiation intensity for direct collapse black hole formation: dependence on the radiation spectral shape

It has been proposed that supermassive black holes (SMBHs) are originated from direct-collapse black holes (DCBHs) that are formed at z & 10 in the primordial gas in the case that H2 cooling is suppressed by strong external radiation. In this work, we study the critical specific intensity J crit required for DCBH formation for various radiation spectral shapes by a series of one-zone calculations of a collapsing primordialgas cloud. We calculate the critical specific intensity at the Lyman-Werner (LW) bands J crit LW,21 (in units of 10 −21 ergs −1 Hz −1 sr −1 cm −2 ) for realistic spectra of metal-poor galaxies. We find J crit is not sensitive to the age or metallicity for the constant star formation galaxies with J crit LW,21 = 1300 1400, while J crit decreases as galaxies become older or more metal-enriched for the instantaneous starburst galaxies. However, such dependence for the instantaneous starburst galaxies is weak for the young or extremely metal-poor galaxies: J crit LW,21 = 1000 1400 for the young (the age less than 100 Myr) galaxies and J crit
Anti-de Sitter strictly GHC-regular groups which are not lattices

For $d=4, 5, 6, 7, 8$, we exhibit examples of $\mathrm{AdS}^{d,1}$ strictly GHC-regular groups which are not quasi-isometric to the hyperbolic space $\mathbb{H}^d$, nor to any symmetric space. This provides a negative answer to Question 5.2 in [9A12] and disproves Conjecture 8.11 of Barbot-M\'erigot [BM12]. We construct those examples using the Tits representation of well-chosen Coxeter groups. On the way, we give an alternative proof of Moussong's hyperbolicity criterion [Mou88] for Coxeter groups built on Danciger-Gu\'eritaud-Kassel [DGK17] and find examples of Coxeter groups $W$ such that the space of strictly GHC-regular representations of $W$ into $\mathrm{PO}_{d,2}(\mathbb{R})$ up to conjugation is disconnected.
Theoretical and experimental evaluation of multilayer porous silicon structures for enhanced erbium up-conversion luminescence

absorption enhancement within slow-light modes is then used to illustrate an increase in absorption over the bulk value: the effective absorption coefficient is shown to increase by more than 22% over a broad spectral region and by more than 400% over a narrow region. Erbium-doped porous silicon photonic crystals are fabricated with the photonic band edge coincident with the 4 I15/2! 4 I13/2 Er 3+ transition. Challenges in fabrication are discussed. An angular-dependent photoluminescence measurement demonstrates emission intensity that varies non-monotonically with the position of the photonic band edge. A maximum of 26.6× enhancement of Er 3+ emission intensity is observed for the 550-nm transition, with lower enhancement factors seen for longer wavelengths.
Turbulent eddy-time-correlation in the solar convective zone

Theoretical modeling of the driving processes of solar-like oscillations is a powerful way of understanding the properties of the convective zones of solar-type stars. In this framework, the description of the temporal correlation between turbulent eddies is an essential ingredient to model mode amplitudes. However, there is a debate between a Gaussian or Lorentzian description of the eddy-time correlation function (Samadi et al. 2003b, AA Chaplin et al. 2005, MNRAS, 360, 859). Indeed, a Gaussian description reproduces the low-frequency shape of the mode amplitude for the Sun, but is unsatisfactory from a theoretical point of view (Houdek 2010, Ap&SS, 328, 237) and leads to other disagreements with observations (Samadi et al. 2007, A&A, 463, 297). These are solved by using a Lorentzian description, but there the low-frequency shape of the solar observations is not correctly reproduced. We reconcile the two descriptions by adopting the sweeping approximation, which consists in assuming that the eddytime-correlation function is dominated by the advection of eddies, in the inertial range, by energy-bearing eddies. Using a Lorentzian function together with a cut-off frequency derived from the sweeping assumption allows us to reproduce the low-frequency shape of the observations. This result also constitutes a validation of the sweeping assumption for highly turbulent flows as in the solar case.
Mental Fatigue, Activities of Daily Living, Sick Leave and Functional Status among Patients with Long COVID: A Cross-Sectional Study

Studies suggest that persistent symptoms after COVID-19 (long COVID) influence functioning and activities of daily living (ADL). However, it is still uncertain how and to what extent. This study aimed to describe patient-reported mental fatigue, ADL problems, ADL ability, sick leave and functional status among patients with long COVID. In this cross-sectional study, 448 patients, ≥18 years old and referred to occupational therapy at a Danish Post-COVID-19 Clinic, were included. Mental fatigue was measured by the Mental Fatigue Scale, ADL problems and ability were measured by the Canadian Occupational Performance Measure, sick leave was self-reported and functional status was evaluated by the Post-COVID-19 Functional Status Scale. Mean age was 46.8 years, 73% of the patients were female, and 75% suffered from moderate to severe mental fatigue. The majority reported difficulties performing productive and leisure activities. The median performance and satisfaction scores were 4.8 and 3, respectively. In total, 56% of the patients were on sick leave, and 94% were referred to rehabilitation. A decrease in functional status was found between pre-COVID-19 and assessment. Conclusively, the patients were highly affected in their everyday life and had distinct rehabilitation needs. Future research is needed to address causalities and rehabilitation for this patient group.
Compact and “compact” operators on standard Hilbert modules over $W^{*}$-algebras

We construct a topology on the standard Hilbert module $l^2(\mathcal A)$ over a unital $W^*$-algebra $\mathcal A$ such that any "compact" operator, (i.e.\ any operator in the norm closure of the linear span of the operators of the form $x\mapsto\left z$) maps bounded sets into totally bounded sets.
Probing the Environment of High-z Quasars Using the Proximity Effect in Projected Quasar Pairs

We have used spectra of 181 projected quasar pairs at separations ≤1.5′ from the Sloan Digital Sky Survey Data Release 12 in the redshift range of 2.5–3.5 to probe the proximity regions of the foreground quasars. We study the proximity effect both in the longitudinal and in the transverse directions, by carrying out a comparison of the Lyα absorption lines originating from the vicinity of quasars to those originating from the general intergalactic medium at the same redshift. We found an enhancement in the transmitted flux within 4 Mpc to the quasar in the longitudinal direction. However, the trend is found to be reversed in the transverse direction. In the longitudinal direction, we derived an excess overdensity profile showing an excess up to r ≤ 5 Mpc after correcting for the quasar’s ionization, taking into account the effect of low spectral resolution. This excess overdensity profile matches with the average overdensity profile in the transverse direction without applying any correction for the effect of the quasar’s ionization. Among various possible interpretations, we found that the anisotropic obscuration of the quasar’s ionization seems to be the most probable explanation. This is also supported by the fact that all of our foreground quasars happen to be type 1 AGNs. Finally, we constrain the average quasar’s illumination along the transverse direction as compared to that along the longitudinal direction to be ≤27% (3σ confidence level).
An Efficient Oceanic Eddy Identification Method With XBT Data Using Transformer

Oceanic mesoscale eddies are relatively small, short-lived circulation patterns that are approximately in geostrophic balance. Meanwhile, eddies are omnipresent and can be characterized by dynamic sea level anomalies and temperature anomalies. This makes the eddy identification mainstream with Sea Level Anomaly (SLA). Unfortunately, nearly 90% of sea level dynamic anomalies caused by oceanic eddies cannot be observed due to insufficient resolution of satellite altimeters. Combining in situ Expendable Bathythermograph (XBT) profiles data, and sea surface temperature data calibrated by the altimeter, this article proposes a deep neural network to identify subsurface oceanic eddies and inverse the corresponding sea surface eddy properties. First, the eddies identified by SLA are purified to match the corresponding vertical profile dataset. Then, a neural network with a self-attention mechanism is constructed by combining the eddy vertical profile structure with temporal and spatial characteristics and external features to effectively identify the eddy. Furthermore, the eddy properties including radius, amplitude, and energy are inversion with XBT profile and SST features. Finally, the experimental results show that the accuracy of eddy classification can reach 98.22%, which demonstrates that vertical profiles can be used to classify eddies effectively. Subsequent reclassification of the outside altimeter-identified eddies recaptured about 36% of the eddies. The authenticity of the newly identified eddies can be demonstrated by statistical model validation as well as validation of sea surface temperature anomaly. These results indicate that the subsurface eddies identification can be implemented by vertical profiles with deep learning.
Disordered graphene and boron nitride in a microwave tight-binding analog

Experiments on hexagonal graphene-like structures using microwave measuring techniques are presented. The lowest transverse-electric resonance of coupled dielectric disks sandwiched between two metallic plates establishes a tight-binding configuration. The nearest-neighbor coupling approximation is investigated in systems with few disks. Taking advantage of the high flexibility of the disks positions, consequences of the disorder introduced in the graphene lattice on the Dirac points are investigated. Using two different types of disks, a boron-nitride-like structure (a hexagonal lattice with a two-atom basis) is implemented, showing the appearance of a band gap.
THE X-RAY VIEW OF ABELL 3120

Identification of Abell 3120 as a galaxy cluster has recently been questioned with alternative suggestions including a fossil remnant of a group merger, non-thermal emission from a radio galaxy, and projected emission from a filamentary string of galaxies. We report on our analysis of the Chandra observation and evaluate these hypotheses based on our results. Abell 3120 shows X-ray emission extending 158 kpc, well beyond the central galaxy. The spatial distribution of X-rays in the core more closely follows the radio emission showing a jet-like structure extending to the north that is misaligned with the stellar light distribution of the central galaxy. At larger radii, the X-ray emission is aligned with the SE–NW running axis of the galaxy distribution in the cluster core. Modeling the X-ray spectrum excludes purely non-thermal emission. The emission-weighted temperature is 1.93–2.19 keV and the 0.3–10 keV luminosity is 1.23 × 1043 erg s−1. Abell 3120 appears to be a poor cluster with Virgo and MKW 4 as peers. The best-fitting model consists of a thermal component and a second component that may be either thermal or non-thermal, with luminosity ∼25% of the total X-ray luminosity. While a more detailed spatial–spectral search failed to detect a central active galactic nucleus, there is some evidence for an extended hard X-ray component. Cooler gas, 1.28–1.80 keV, was detected in the central 20 kpc. The second thermal component marginally requires a higher redshift, >0.12, which may be due to a second cluster in the rich surrounding environment consisting of nearly a thousand cataloged galaxies.