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The Hubble tension refers to the significant discrepancy in the Hubble constant $H_{0}$ obtained from two different measurement methods in cosmology. One method derives data from the Cosmic Microwave Background (CMB) observations by the Planck satellite, yielding a value of $67.4\pm{0.5} \ \mathrm{km\ s^{-1}} \mathrm{Mpc^{-1}} $, while the other method relies on direct measurements of Type Ia supernovae, producing a value $73.04\pm{1.04} \ \mathrm{km\ s^{-1}} \mathrm{Mpc^{-1}} $. This issue has persisted for several years. To theoretically explore potential solutions to this problem, this paper examines a model within the framework of Einstein-Cartan (EC) theory, where torsion is introduced with spin as the corresponding entity, allowing for the assumption $H = -\alpha \phi$. By employing the Markov Chain Monte Carlo (MCMC) algorithm and utilizing Cosmic Chronometers (CC) data, we impose parameter constraints on various parameters in the Friedmann equations, particularly focusing on the curvature density parameter $\Omega_k$, to assess whether the model remains stable under this assumption and whether the estimated parameters align more closely with either of the observational results. In conclusion, we find that the parameter constraints in the model incorporating torsion ($ H_0 = 67.6^{+2.1}_{-2.7} \ \mathrm{km\ s^{-1}\ Mpc^{-1}}$, obtained under the Big Bang Nucleosynthesis (BBN) constraint with $\Omega_{k}=0$; $ H_0 = 66.2^{+4.4}_{-2.9} \ \mathrm{km\ s^{-1}\ Mpc^{-1}}$, obtained under same constraint but set $\Omega_{k}$ as a free variable; $ H_0 = 68.8^{+2.9}_{-4.2} \ \mathrm{km\ s^{-1}\ Mpc^{-1}}$, obtained under the Planck constraint) are more consistent with the value derived from CMB data, favoring the lower $H_0$ value., Comment: 13 pages,5 figures

Underwater vehicles have seen significant development over the past seventy years. However, bio-inspired propulsion robots are still in their early stages and require greater interdisciplinary collaboration between biologists and roboticists. The octopus, one of the most intelligent marine animals, exhibits remarkable abilities such as camouflaging, exploring, and hunting while swimming with its arms. Although bio-inspired robotics researchers have aimed to replicate these abilities, the complexity of designing an eight-arm bionic swimming platform has posed challenges from the beginning. In this work, we propose a novel bionic robot swimming platform that combines asymmetric passive morphing arms with an umbrella-like quick-return mechanism. Using only two simple constant-speed motors, this design achieves efficient swimming by replicating octopus-like arm movements and stroke time ratios. The robot reached a peak speed of 314 mm/s during its second power stroke. This design reduces the complexity of traditional octopus-like swimming robot actuation systems while maintaining good swimming performance. It offers a more achievable and efficient platform for biologists and roboticists conducting more profound octopus-inspired robotic and biological studies.

Based on QCD sum rules, we investigate the twist-2 distribution amplitudes of the scalar mesons $a_{0}(980)$ and $a_{0}(1450)$. We have derived the moments for these scalar mesons, composed of two constituent valence quarks, to the first order by selecting appropriate correlation functions. Subsequently, we have determined the first two Gegenbauer coefficients of these scalar mesons, employing these moments, we further analyze the twist-2 light-cone distribution amplitudes for the $a_{0}$ meson. The paper concludes with an examination of the weak decay widths for the transitions $B,D\rightarrow a_{0}$., Comment: 13 pages,6 figures

The Varying Speed of Light (VSL) model describes how the speed of light in a vacuum changes with cosmological redshift. Despite numerous models, there is little observational evidence for this variation. While the speed of light can be accurately measured by physical means, cosmological methods are rarely used. Previous studies quantified the speed of light at specific redshifts using Gaussian processes and reconstructed the redshift-dependent function $c(z)$. It is crucial to quantify the speed of light across varying redshifts. We use the latest data on angular diameter distances $D_A(z)$ and Hubble parameters $H(z)$ from baryon acoustic oscillation (BAO) and cosmic chronometer measurements in the redshift interval $z\in[0.07,1.965]$. The speed of light $c(z)$ is determined using Gaussian and deep Gaussian processes to reconstruct $H(z)$, $D_A(z)$, and $D^{\prime}_A(z)$. Furthermore, we conduct comparisons across three distinct models, encompassing two renowned VSL models. We get the result of the parameters constraints in the models (1) for the ``$c$-c" model, $c_0=29492.6 \pm^{6.2}_{5.3} \mathrm{~km} \mathrm{~s}^{-1}$. (2) For the ``$c$-cl" model, $c_0=29665.5 \pm^{11.2}_{11.4}\mathrm{~km} \mathrm{~s}^{-1}$ and $n=0.05535 \pm^{0.00008}_{0.00007}$. (3) For the ``$c$-CPL" model, $c_0=29555.7 \pm^{13.3}_{13.2} \mathrm{~km} \mathrm{~s}^{-1}$ and $n=-0.0607 \pm 0.0001$. Based on our findings, it may be inferred that Barrow's classical VSL model is not a suitable fit for our data. In contrast, the widely recognized Chevallier-Polarski-Linder (CPL) VSL model, under some circumstances, as well as the universal ``c is constant" model, demonstrate a satisfactory ability to account for our findings., Comment: 15 pages, 9 figures; Accepted for publication in MNRAS

In the past two decades, the exploration of quantumness within Schwarzschild spacetime has garnered significant interest, particularly regarding the Hawking radiation's impact on quantum correlations and quantum coherence. Building on this foundation, we investigate how Hawking radiation influences maximal steered coherence (MSC)-a crucial measure for gauging the ability to generate coherence through steering. We find that as the Hawking temperature increases, the physically accessible MSC degrade while the unaccessible MSC increase. This observation is attributed to a redistribution of the initial quantum correlations, previously acknowledged by inertial observers, across all bipartite modes. In particular, we find that in limit case that the Hawking temperature tends to infinity, the accessible MSC equals to 1/\sqrt{2} of its initial value, and the unaccessible MSC also equals to the same value. Our findings illuminate the intricate dynamics of quantum information in the vicinity of black holes, suggesting that Hawking radiation plays a pivotal role in reshaping the landscape of quantum coherence and entanglement in curved spacetime. This study not only advances our theoretical understanding of black hole thermodynamics but also opens new avenues for investigating the interface between quantum mechanics and general relativity., Comment: 4 pages, 1 figure

Recent studies have increasingly focused on the effect of relativistic motion on quantum coherence. Prior research predominantly examined the influence of relative motion on basis-dependent quantum coherence, underscoring its susceptibility to decoherence under accelerated conditions. Yet, the effect of relativistic motion on basis-independent quantum coherence, which is critical for understanding the intrinsic quantum features of a system, remains an interesting open question. This paper addresses this question by examining how total, collective, and localized coherence are affected by acceleration and coupling strength. Our analysis reveals that both total and collective coherence significantly decrease with increasing acceleration and coupling strength, ultimately vanishing at high levels of acceleration. This underscores the profound impact of Unruh thermal noise. Conversely, localized coherence exhibits relative stability, decreasing to zero only under the extreme condition of infinite acceleration. Moreover, we demonstrate that collective, localized, and basis-independent coherence collectively satisfy the triangle inequality. These findings are crucial for enhancing our understanding of quantum information dynamics in environments subjected to high acceleration and offer valuable insights on the behavior of quantum coherence under relativistic conditions., Comment: 7 pages, 3 figures

This work focuses on the regularization by nonlinear noise for a class of partial differential equations that may only have local solutions. In particular, we obtain the global existence, uniqueness and the Feller property for stochastic 3D Navier-Stokes equations, which provide positive answers to a longstanding open problem in this field. Moreover, we discover a new phenomenon that for a potentially explosive deterministic system, an appropriate intervention of nonlinear noise can not only prevent blow-up but also lead to the finite time extinction of the associated stochastic system. Our main results have broad applications, including stochastic $p$-Laplace equations with heat sources, stochastic surface growth models and stochastic quasi-geostrophic equations., Comment: 56 Pages

Precision space inertial sensors are imperative to Earth geodesy missions, gravitational wave observations and several fundamental physics experiments in space. In these missions, the residual acceleration noise of the test mass(TM) caused by the forces from inertial sensor components and environment is supposed to be kept below a certain level. As a number of forces contributing to residual acceleration are related to actuation system, developing a precise actuation system to exclude any erroneous force and obtain an ultra sensitive value for TM acceleration noise is necessary and essential. However, it is difficult to test the actuation system on ground. In this paper, a torsion pendulum is established to test the influence of actuation system on TM torque noise and a closed-loop control system combined torsion pendulum and parts of actuation modules is designed to assess the performance of actuation control algorithm. The experimental results show that the parameters in an actuation system will introduce additional torque noise and the maximum noise can reach as much as 10^{-13}Nm /Hz^{1/2} at 1 mHz. The stable tracking error for the closed-loop system is about 10^{-7}, indicating that the combination system achieves good tracking performance and robustness for TM rotation control in different conditions of inertial sensors., Comment: 9 pages, 14 figures

In this paper, a compact wideband dual-polarized Luneburg lens antenna (LLA) with reduced anisotropy and improved impedance matching is proposed in Ka band with a wide 2D beamscanning capability. Based on transformation optics, the spherical Luneburg lens is compressed into a cylindrical one, while the merits of high gain, broad band, wide scanning, and free polarization are preserved. A trigonometric function is employed to the material property of the flattened Luneburg lens with reduced anisotropy, thus effectively alleviates the strong reflection, the high sidelobes and back radiation with a free cost on the antenna weight and volume. Furthermore, a light thin wideband 7-by-1 metasurface phased array is studied as the primary feed for the LLA. The proposed metantenna, shorted for metamaterial-based antenna, has a high potential for B5G, future wireless communication and radar sensing as an onboard system.

Many previous works studied the dynamical timescale mass transfer stability criteria based on the donor response with neglecting the stellar structure of the accretor. In this letter, we investigate the radial response of accretors with mass accumulation and its effect on the binary mass transfer stability. We perform a series of detailed stellar evolution simulations with different types of accretors and obtain the radial variations of stars accreting at different rates. Since the time within which the donor loses half of the original mass has a correlation with the donor mass, we approximately obtain the mean mass transfer rate as a function of mass ratio. Assuming that the common envelope (CE) phase occurs if the accretor radius exceeds the outer Roche lobe radius, we obtain the critical mass ratio of dynamically unstable mass transfer. We find the critical mass ratios for donors filling their Roche lobes at the Main Sequence (MS) and Hertzsprung Gap (HG) stages are smaller than that derived from the radial response of the donor in the traditional way. Our results may suggest that the binary is easier to enter into the CE phase for a donor star at the MS or HG stage than previously believed., Comment: 7 pages,9 figures, accepted for publication in MNRAS

3-dB couplers, which are commonly used in photonic integrated circuits for on-chip information processing, precision measurement, and quantum computing, face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication errors. To address this, we introduce topological physics to nanophotonics, developing a framework for topological 3-dB couplers. These couplers exhibit broad working wavelength range and robustness against fabrication dimensional errors. By leveraging valley-Hall topology and mirror symmetry, the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering matrix. Tolerance analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 20 nm. We further propose a topological interferometer for on-chip distance measurement, which also exhibits robustness against dimensional errors. This extension of topological principles to the fields of interferometers, may open up new possibilities for constructing robust wavelength division multiplexing, temperature-drift-insensitive sensing, and optical coherence tomography applications., Comment: 20 pages, 4 figures

Negative refractive index (NRI) of the mescopic dissipative left-handed transmission line (LHTL) is manipulated by the displaced squeezed Fock state (DSFS) and the dissipation presented by the resistance and conductance. Comparing to the classical LHTL, some specific quantum characteristics are shown in the LHTL because of quantum effect, which will be significant to its miniaturization application in microwave frequency., Comment: 5 pages, 4 figures

The EHT has captured a series of images of black holes. These images could provide valuable information about the gravitational environment near the event horizon. However, accurate detection and parameter estimation for candidate black holes are necessary. This paper explores the potential for identifying black holes in the ultraviolet band using space telescopes. We establish a data pipeline for generating simulated observations and present an ensemble neural network model for black hole detection and parameter estimation. The model achieves mean average precision [0.5] values of 0.9176 even when reaching the imaging FWHM ($\theta_c$) and maintains the detection ability until $0.54\theta_c$. The parameter estimation is also accurate. These results indicate that our methodology enables super-resolution recognition. Moreover, the model successfully detects the shadow of M87* from background noise and other celestial bodies and estimates its inclination and positional angle. Our work demonstrates the feasibility of detecting black holes in the ultraviolet band and provides a new method for black hole detection and further parameter estimation., Comment: 20 pages, 17 figures, 9 tables. We propose a ensemble neural network which demonstrates the feasibility of detecting black holes in the UV band and provides a new method for the accurate and real-time detection of candidate black holes and further parameter estimation

This paper is devoted to proving the small noise asymptotic behaviour, particularly large deviation principle, for multi-scale stochastic dynamical systems with fully local monotone coefficients driven by multiplicative noise. The main techniques are based on a combination of the weak convergence approach, the time discretization technique and the theory of pseudo-monotone operator. The main results derived in this paper have broad applicability to various multi-scale models, where the slow component could be such as stochastic porous medium equations, stochastic Cahn-Hilliard equations and stochastic 2D Liquid crystal equations., Comment: 40 pages

We investigate the weak decays of the triply heavy baryon $\Omega_{QQQ}$ in the light-front quark model. Since $\Omega_{QQQ}$ consists of three indistinguishable identical heavy quarks, the commonly adopted quark-diquark picture does not seem to be valid anymore. Instead, we employ the three-quark picture for baryons where the three quarks are regarded as individual quarks. We calculate the hadronic form factors for the transitions and give predictions for the decay widths of the semi-leptonic decay modes $\Omega_{ccc}\to \Xi_{cc}/ \Omega_{cc}+ l\bar{\nu}_l$, $\Omega_{bbb}\to \Xi _{bb}+ l \bar{\nu}_l$ and the non-leptonic decay modes $\Omega_{ccc}\to \Xi_{cc}/\Omega_{cc}+ M$, $\Omega_{bbb}\to \Xi_{bb}+ M$. Our study can be a guide for future experiments to discover the triply heavy baryons., Comment: 16 pages, 5 figures

Complex systems are not entirely decomposable, hence interdependences arise at the interfaces in complex projects. When changes occur, significant risks arise at these interfaces as it is hard to identify, manage and visualise the systemic consequences of changes. Particularly problematic are the interfaces in which there are multiple interdependencies, which occur where the boundaries between design components, contracts and organisation coincide, such as between design disciplines. In this paper, we propose an approach to digital twin-based interface management, through an underpinning state-of-the-art review of the existing technical literature and a small pilot to identify the characteristics of future data-driven solutions. We set out an approach to digital twin-based interface management and an agenda for research on advanced methodologies for managing change in complex projects. This agenda includes the need to integrate work on identifying systems interfaces, change propagation and visualisation, and the potential to significantly extend the limitations of existing solutions by using developments in the digital twin, such as linked data, semantic enrichment, network analyses, natural language processing (NLP)-enhanced ontology and machine learning., Comment: 11 pages, 5 figures

Recently, the LHCb collaboration has observed the decays $\Xi^0_{b}\to\Xi^+_{c}D^-_s$ and $\Xi^-_{b}\to\Xi^0_{c}D^-_s$. They measured the relative branching fractions times the ratio of beauty-baryon production cross-sections $\mathcal{R}(\frac{\Xi^0_b}{\Lambda_b})\equiv\frac{\sigma(\Xi_b^0)}{\sigma(\Lambda^0_b)}\times\frac{B(\Xi^0_{b}\to\Xi^+_{c}D^-_s)}{B(\Lambda^0_{b}\to\Lambda^+_{c}D^-_s)}$ and $\mathcal{R}(\frac{\Xi^-_b}{\Lambda_b})\equiv\frac{\sigma(\Xi^-_b)}{\sigma(\Lambda^0_b)}\times\frac{B(\Xi^-_{b}\to\Xi^0_{c}D^-_s)}{B(\Lambda^0_{b}\to\Lambda^+_{c}D^-_s)}$. Once the ratio $\frac{\sigma(\Xi_b^0)}{\sigma(\Lambda^0_b)}$ or $\frac{\sigma(\Xi_b^-)}{\sigma(\Lambda^0_b)}$ is known, one can determine the relative branching fractions which can be used to exam the mixing of $\Xi_c$ and $\Xi'_c$. In previous literature, $\Xi_c$ and $\Xi'_c$ were assumed to belong to SU(3)$_F$ antitriple and sextet, respectively. However, recent experimental measurements such as the ratio $\Gamma(\Xi_{cc}\to\Xi_c\pi^+)/\Gamma(\Xi_{cc}\to\Xi'_c\pi^+)$ indicate the spin-flavor structures of $\Xi_{c}$ and $\Xi'_{c}$ are a mixture of $\Xi^{\bar 3}_{c}$ and $\Xi^{6}_{c}$. The exact value of mixing angle $\theta$ is still under debate. In theoretical models, the mixing angle was fitted to be about $16.27^\circ\pm2.30^\circ$ or $85.54^\circ\pm2.30^\circ$ based on decay channels $\Xi_{cc} \to\Xi^{(')}_{cc} $. While in lattice calculation, a small angle ($1.2^\circ\pm0.1^\circ$) is preferred. To address such discrepancy and test the mixing of $\Xi_c$ and $\Xi'_c$, here we propose the analysis of semileptonic and non-leptonic decays of $\Xi_{b}\to\Xi_{c}$ and $\Xi_{b}\to\Xi^{'}_{c}$. We calculate the decay rate of $\Xi_{b}\to\Xi_{c}$ and $\Xi_{b}\to\Xi^{'}_{c}$ based on light-front quark model and study the effect of the mixing angle on the ratios of weak decays $\Xi_{b}\to\Xi_{c}$ and $\Xi_{b}\to\Xi^{'}_{c}$....., Comment: 12 pages, 4 figures and 8 tables

Electron-capture supernovae (EC-SNe) provide an alternative channel for producing neutron stars (NSs). They play an important role in the formation of double NS (DNS) systems and the chemical evolution of galaxies, and contribute to the NS mass distribution in observations. It is generally believed that EC-SNe originate from $e$-captures on $\rm^{24}Mg$ and $\rm^{20}Ne$ in the massive degenerate oxygen-neon (ONe) cores with masses close to the Chandrasekhar limit ($M_{\rm Ch}$). However, the origin of EC-SNe is still uncertain. In this paper, we systematically studied the EC-SNe in NS+He star systems by considering the explosive oxygen burning that may occur in the near-$M_{\rm Ch}$ ONe core. We provided the initial parameter spaces for producing EC-SNe in the initial orbital period $-$ initial He star mass (log$P_{\rm orb}^{\rm i}-M_{\rm He}^{\rm i}$) diagram, and found that both $M_{\rm He}^{\rm i}$ and minimum $P_{\rm orb}^{\rm i}$ for EC-SNe increase with metallicity. Then, by considering NS kicks added to the newborn NS, we investigated the properties of the formed DNS systems after the He star companions collapse into NSs, such as the orbital periods, eccentricities and spin periods of recycle pulsars ($P_{\rm spin}$), etc. The results show that most of the observed DNS systems can be produced by NS kicks of $\lesssim50\rm\,km\,s^{-1}$. In addition, we found that NSs could accrete more material if the residual H envelope on the He star companions is considered, which can form the mildly recycled pulsars ($P_{\rm spin}\sim20\,$ms) in DNS systems., Comment: 13 pages, 14 figures, 3 tables, accepted for publication in MNRAS, comments welcome!