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We develop tight bounds for the covert capacity of slotted asynchronous binary-input Discrete Memoryless Channels (DMCs) and Additive White Gaussian Noise (AWGN) channels, in which a codeword is transmitted in one of several slots with known boundaries, where the number of slots is sub-exponential in the codeword length. Our upper and lower bounds are within a multiplicative factor of $\sqrt{2}$ independent of the channel. This result partially fills a characterization gap between the covert capacity without asynchronism and the covert capacity with exponential asynchronism. Our key technical contributions consist of i) a tight upper bound for the relative entropy characterizing the effect of asynchronism on the covertness constraint in our achievability proof; ii) a careful converse analysis to characterize the maximum allowable weight or power of codewords to meet the covertness constraint. Our results suggest that, unlike the case without asynchronism, the choice of covertness metric does not change the covert capacity in the presence of asynchronism., Comment: 24 pages, 2 figures, submitted to TIT

We derive self-consistent constraint conditions for collision terms in quantum kinetic theory within Wigner function formalism. We present simple specific solutions for the collision terms in quantum kinetic theory which is compatible with these constraints. We obtain the self-consistent quantum kinetic theory at relaxation-time approximation, with which we discuss spin polarization effects and electric charge separation effects in relativistic heavy-ion collisions., Comment: 24 pages

Coupled angular momentum eigenstates are widely used in atomic and nuclear physics calculations, and are building blocks for spin networks and the Schur transform. To combine two angular momenta $\mathbf{J}_1$ and $\mathbf{J}_2$, forming eigenstates of their total angular momentum $\mathbf{J}=\mathbf{J}_1+\mathbf{J}_2$, we develop a quantum-walk scheme that does not require inputting $O(j^3)$ nonzero Clebsch-Gordan (CG) coefficients classically. In fact, our scheme may be regarded as a unitary method for computing CG coefficients on quantum computers with a typical complexity of $O(j)$ and a worst-case complexity of $O(j^3)$. Equivalently, our scheme provides decompositions of the dense CG unitary into sparser unitary operations. Our scheme prepares angular momentum eigenstates using a sequence of Hamiltonians to move an initial state deterministically to desired final states, which are usually highly entangled states in the computational basis. In contrast to usual quantum walks, whose Hamiltonians are prescribed, we engineer the Hamiltonians in $\mathfrak{su}(2)\times \mathfrak{su}(2)$, which are inspired by, but different from, Hamiltonians that govern magnetic resonances and dipole interactions. To achieve a deterministic preparation of both ket and bra states, we use projection and destructive interference to double pinch the quantum walks, such that each step is a unit-probability population transfer within a two-level system. We test our state preparation scheme on classical computers, reproducing CG coefficients. We also implement small test problems on current quantum hardware., Comment: 26 pages total, 17 pages main text, 8 figures

The charmed $ \Lambda_{c}^{+} $ hypernuclei are investigated within the framework of the density-dependent relativistic mean-field (DDRMF) theory. Starting from the empirical hyperon potential in symmetric nuclear matter, obtained through microscopic first-principle calculations, two sets of $\Lambda_c N$ effective interactions were derived by fitting the potentials with minimal uncertainty (Fermi momentum $k_{F,n} = 1.05~\rm{fm}^{-1}$) and near saturation density ($k_{F,n} = 1.35~\rm{fm}^{-1}$). These DDRMF models were then used to explore the $\Lambda_{c} N$ effective interaction uncertainties on the description of hypernuclear bulk and single-particle properties. A systematic investigation was conducted on the existence of bound $\Lambda_{c}^{+}$ hypernuclei. The dominant factors affecting the existence and stability of hypernuclei were analyzed from the perspective of the $\Lambda_{c}^{+}$ potential. It is found that the hyperon potential is not only influenced by the Coulomb repulsion, but by an extra contribution from the rearrangement terms due to the density dependence of the meson-baryon coupling strengths. Therefore, the rearrangement term significantly impacts the stability description for light hypernuclei, while for heavier hypernuclei, the contribution from Coulomb repulsion becomes increasingly significant and eventually dominant. The discussion then delves into the bulk and single-particle properties of charmed hypernuclei using these models. It is found that even when different models yield similar hyperon potentials for nuclear matter, different treatments of nuclear medium effects could lead to disparities in the theoretical description of hypernuclear structures. This study indicates that constraints on the $ \Lambda_{c} N $ interaction at finite densities are crucial for the study of $ \Lambda_{c}^{+} $ hypernuclear structures., Comment: 15 pages, 8 figures, 3 tables

The inclusive production of pseudoscalar heavy quarkoniua ($\eta_c,~\eta_b$ and $B_c$) via photon-photon fusion in heavy ion ultraperipheral collision (UPC) are calculated to QCD next-to-leading order in the framework of non-relativistic QCD (NRQCD). The total cross section of $\eta_c$ produced in Pb-Pb UPC is 194 $\mathrm{nb}^{-1}$ and 1052 $\mathrm{nb}^{-1}$ at nucleon-nucleon c.m. energies $\sqrt{S_{\mathrm{NN}}}=$ 5.52 TeV and 39.4 TeV, respectively. The cross sections for $\eta_b$ and $B_c$ mesons are more than two to three orders of magnitude smaller. We make a detailed phenomenological analysis on the $\eta_c$ production; the uncertainties caused by the renormalization scale and the charm quark mass, the cross sections in other ultraperipheral nucleon-nucleon colliding systems, and the transverse momentum distribution are discussed. At the coming HL-LHC and future FCC, the heavy ion UPC opens another door of the study on the production of heavy quarkonium., Comment: 16 pages, 1 figures, 4 tables

The cosmic 21 cm signal serves as a crucial probe for studying the evolutionary history of the Universe. However, detecting the 21 cm signal poses significant challenges due to its extremely faint nature. To mitigate the interference from the Earth's radio frequency interference (RFI), the ground and the ionospheric effects, the Discovering the Sky at the Longest Wavelength (DSL) project will deploy a constellation of satellites in Lunar orbit, with its high-frequency daughter satellite tasked with detecting the global 21 cm signal from cosmic dawn and reionization era (CD/EoR). We intend to employ the Vari-Zeroth-Order Polynomial (VZOP) for foreground fitting and subtracting. We have studied the effect of thermal noise, thermal radiation from the Moon, the Lunar reflection, anisotropic frequency-dependent beam, inaccurate antenna beam pattern, and RFI contamination. We discovered that the RFI contamination can significantly affect the fitting process and thus prevent us from detecting the signal. Therefore, experimenting on the far side of the moon is crucial. We also discovered that using VZOP together with DSL, after 1080 orbits around the Moon, which takes about 103 days, we can successfully detect the CD/EoR 21 cm signal., Comment: 15 pages, 17 figures, to be submitted to SCPMA

Simulating plasma physics on quantum computers is difficult because most problems of interest are nonlinear, but quantum computers are not naturally suitable for nonlinear operations. In weakly nonlinear regimes, plasma problems can be modeled as wave-wave interactions. In this paper, we develop a quantization approach to convert nonlinear wave-wave interaction problems to Hamiltonian simulation problems. We demonstrate our approach using two qubits on a superconducting device. Unlike a photonic device, a superconducting device does not naturally have the desired interactions in its native Hamiltonian. Nevertheless, Hamiltonian simulations can still be performed by decomposing required unitary operations into native gates. To improve experimental results, we employ a range of error mitigation techniques. Apart from readout error mitigation, we use randomized compilation to transform undiagnosed coherent errors into well-behaved stochastic Pauli channels. Moreover, to compensate for stochastic noise, we rescale exponentially decaying probability amplitudes using rates measured from cycle benchmarking. We carefully consider how different choices of product-formula algorithms affect the overall error and show how a trade-off can be made to best utilize limited quantum resources. This study provides an example of how plasma problems may be solved on near-term quantum computing platforms., Comment: 26 pages, 5 figures

In hypernuclear systems, interactions involving nucleons and hyperons are intricately influenced by the surrounding particles, particularly by the density and isospin feature of the nuclear medium. In this work, the relativistic mean-field (RMF) theory is adopted to describe the structure of several typical $ \Xi^{-} $ hypernuclei. New sets of $\Xi N$ effective interactions, by taking a density-dependent meson-nucleon/hyperon coupling perspective, are developed by fitting experimental data on the $\Xi^{-}$ hyperon $1s$ and $1p$ state separation energy of $^{15}_{\Xi^{-}}$C. It is found that the density-dependent behavior of meson-hyperon coupling strengths sensitively affects the description of hyperon single-particle levels, which play a crucial role in the consistent description of the theoretical and experimental separation energies of $\Xi^{-}$ $1s$ and $1p$ states in $^{15}_{\Xi^{-}}$C. In fact, the density-dependent meson-baryon coupling strengths introduce additional rearrangement contributions in the hyperon self-energy. Correspondingly, detailed forms of density dependence in these coupling strengths and different consideration of meson-baryon coupling channels will impact the hyperon single-particle properties within hypernuclei. Especially with the additional inclusion of isovector scalar $\delta$ meson, the significant enhancement of rearrangement terms in the effective interaction DD-ME$ \delta $ impacts the shape of the hyperon potential and alters the characteristics of the isovector channel dynamics balance in the effective nuclear force. Such effects may be crucial for describing hyperon separation energies in specific $\Xi^{-}$ hypernuclei such as $^{12}_{\Xi^{-}}$Be and in hypernuclei with higher mass numbers. Relevant research underscores the importance of precisely accounting for medium effects in hyperon-nucleon interactions., Comment: 12 pages, 3 figures, 3 tables

Image restoration is a critical task in low-level computer vision, aiming to restore high-quality images from degraded inputs. Various models, such as convolutional neural networks (CNNs), generative adversarial networks (GANs), transformers, and diffusion models (DMs), have been employed to address this problem with significant impact. However, CNNs have limitations in capturing long-range dependencies. DMs require large prior models and computationally intensive denoising steps. Transformers have powerful modeling capabilities but face challenges due to quadratic complexity with input image size. To address these challenges, we propose VmambaIR, which introduces State Space Models (SSMs) with linear complexity into comprehensive image restoration tasks. We utilize a Unet architecture to stack our proposed Omni Selective Scan (OSS) blocks, consisting of an OSS module and an Efficient Feed-Forward Network (EFFN). Our proposed omni selective scan mechanism overcomes the unidirectional modeling limitation of SSMs by efficiently modeling image information flows in all six directions. Furthermore, we conducted a comprehensive evaluation of our VmambaIR across multiple image restoration tasks, including image deraining, single image super-resolution, and real-world image super-resolution. Extensive experimental results demonstrate that our proposed VmambaIR achieves state-of-the-art (SOTA) performance with much fewer computational resources and parameters. Our research highlights the potential of state space models as promising alternatives to the transformer and CNN architectures in serving as foundational frameworks for next-generation low-level visual tasks., Comment: 23 pages

This paper delves into a nonparametric estimation approach for the interaction function within diffusion-type particle system models. We introduce two estimation methods based upon an empirical risk minimization. Our study encompasses an analysis of the stochastic and approximation errors associated with both procedures, along with an examination of certain minimax lower bounds. In particular, we show that there is a natural metric under which the corresponding minimax estimation error of the interaction function converges to zero with parametric rate. This result is rather suprising given complexity of the underlying estimation problem and rather large classes of interaction functions for which the above parametric rate holds.

Multi-modal Large Language Models (MLLMs) have a significant impact on various tasks, due to their extensive knowledge and powerful perception and generation capabilities. However, it still remains an open research problem on applying MLLMs to low-level vision tasks. In this paper, we present a simple MLLM-based Image Restoration framework to address this gap, namely Multi-modal Large Language Model based Restoration Assistant (LLMRA). We exploit the impressive capabilities of MLLMs to obtain the degradation information for universal image restoration. By employing a pretrained multi-modal large language model and a vision language model, we generate text descriptions and encode them as context embedding with degradation information for the degraded image. Through the proposed Context Enhance Module (CEM) and Degradation Context based Transformer Network (DC-former), we integrate these context embedding into the restoration network, contributing to more accurate and adjustable image restoration. Based on the dialogue with the users, our method leverages image degradation priors from MLLMs, providing low-level attributes descriptions of the input low-quality images and the restored high-quality images simultaneously. Extensive experiments demonstrate the superior performance of our LLMRA in universal image restoration tasks.

The finite mass of the heavy quark suppresses the collimated radiations, which is generally referred to as the dead cone effect. In this paper, we study the distribution of hadron multiplicity over the hadron opening angle with respect to the jet axis in various flavors of jets. The corresponding measurement can be the most straightforward and simplest to explore the dynamical evolution of the radiations in the corresponding jet, which can expose the mass effect. We also propose the transverse energy-weighted angular distribution which sheds light on the interplay between perturbative and nonperturbative effects in the radiation. With Monte-Carlo simulations, our calculation shows that the dead cone effect can be clearly seen by taking the ratio between the b jet and the light-quark (inclusive) jet, promising to be measured at the LHC in the future., Comment: 7 pages, 4 figures; published version in CPC

Multimode squeezed states of light have been proposed as a resource for achieving quantum advantage in computing and sensing. Recent experiments that demonstrate multimode Gaussian states to this end have most commonly opted for spatial or temporal modes, whereas a complete system based on frequency modes has yet to be realized. Instead, we show how to use the frequency modes simultaneously squeezed in a conventional, single-spatial-mode, optical parametric amplifier when pumped by ultrashort pulses. Specifically, we show how adiabatic frequency conversion can be used not only to convert the quantum state from infrared to visible wavelengths, but to concurrently manipulate the joint spectrum. This near unity-efficiency quantum frequency conversion, over a bandwidth >45 THz and, to our knowledge, the broadest to date, allows us to measure the state with an electron-multiplying CCD (EMCCD) camera-based spectrometer, at non-cryogenic temperatures. We demonstrate the squeezing of >400 frequency modes, with a mean of approximately 700 visible photons per shot. Our work shows how many-mode quantum states of light can be generated, manipulated, and measured with efficient use of hardware resources -- in our case, using one pulsed laser, two nonlinear crystals, and one camera. This ability to produce, with modest hardware resources, large multimode squeezed states with partial programmability motivates the use of frequency encoding for photonics-based quantum information processing.

This paper investigates the estimation of the interaction function for a class of McKean-Vlasov stochastic differential equations. The estimation is based on observations of the associated particle system at time $T$, considering the scenario where both the time horizon $T$ and the number of particles $N$ tend to infinity. Our proposed method recovers polynomial rates of convergence for the resulting estimator. This is achieved under the assumption of exponentially decaying tails for the interaction function. Additionally, we conduct a thorough analysis of the transform of the associated invariant density as a complex function, providing essential insights for our main results.

Treating the $X(4140)$ as a compact $J^{PC}=1^{++}$ $cs\bar{c}\bar{s}$ state and using its mass as a reference scale, we systematically estimate the masses of doubly heavy tetraquark states $QQ\bar{q}\bar{q}$ where $Q=c,b$ and $q=u,d,s$. Their decay properties are studied with a simple rearrangement scheme. Based on our results, the lowest $I(J^P)=0(1^+)$ $bb\bar{n}\bar{n}$ state is a stable tetraquark about 20 MeV below the $\bar{B}^*\bar{B}$ threshold. The mass and width of the low-mass $0(1^+)$ $cc\bar{n}\bar{n}$ ($n=u,d$) tetraquark are compatible with the $T_{cc}(3875)^+$ observed by the LHCb Collaboration. The location of the lowest $0(0^+)$ and $0(1^+)$ $bc\bar{n}\bar{n}$ states are found to be close to the $\bar{B}D$ and $\bar{B}^*D$ thresholds, respectively. We hope that the predicted ratios between partial widths of different channels may be helpful to identify compact tetraquark states from future measurements., Comment: 16 pages,3 figures,10 tables

Color-guided depth map super-resolution (CDSR) improve the spatial resolution of a low-quality depth map with the corresponding high-quality color map, benefiting various applications such as 3D reconstruction, virtual reality, and augmented reality. While conventional CDSR methods typically rely on convolutional neural networks or transformers, diffusion models (DMs) have demonstrated notable effectiveness in high-level vision tasks. In this work, we present a novel CDSR paradigm that utilizes a diffusion model within the latent space to generate guidance for depth map super-resolution. The proposed method comprises a guidance generation network (GGN), a depth map super-resolution network (DSRN), and a guidance recovery network (GRN). The GGN is specifically designed to generate the guidance while managing its compactness. Additionally, we integrate a simple but effective feature fusion module and a transformer-style feature extraction module into the DSRN, enabling it to leverage guided priors in the extraction, fusion, and reconstruction of multi-model images. Taking into account both accuracy and efficiency, our proposed method has shown superior performance in extensive experiments when compared to state-of-the-art methods. Our codes will be made available at https://github.com/shiyuan7/DSR-Diff.

Weak gravitational lensing is an invaluable tool for understanding fundamental cosmological physics. An unresolved issue in weak lensing cosmology is to accurately reconstruct the lensing convergence $\kappa$ maps from discrete shear catalog with survey masks, which the seminal Kaiser-Squire (KS) method is not designed to address. We present the Accurate Kappa Reconstruction Algorithm for masked shear catalog (AKRA) to address the issue of mask. AKRA is built upon the prior-free maximum likelihood mapmaking method (or the unbiased minimum variance linear estimator). It is mathematically robust in dealing with mask, numerically stable to implement, and practically effective in improving the reconstruction accuracy. Using simulated maps with mask fractions ranging from 10\% to 50\% and various mask shapes, we demonstrate that AKRA outperforms KS at both the map level and summary statistics such as the auto power spectrum $C_\kappa$ of the reconstructed map, its cross-correlation coefficient $r_\ell$ with the true $\kappa $ map, the scatter plot and the localization measure. Unlike the Wiener filter method, it adopts no priors on the signal power spectrum, and therefore avoids the Wiener filter related biases at both the map level and cross-correlation statistics. If we only use the reconstructed map in the unmasked regions, the reconstructed $C_\kappa$ is accurate to $1\%$ or better and $1-r_\ell \lesssim 1\%$ (excluding $\ell$ at the smallest scales investigated), even for extreme cases of mask fraction and shape. As the first step, the current version of AKRA only addresses the mask issue and therefore ignores complexities such as curved sky and inhomogeneous shape measurement noise. AKRA is capable of dealing with these issues straightfowrardly, and will be addressed in the next version., Comment: 17 pages; 21 figures; Published by Physical Review D. Comments are welcome!

We study the spectrum and rearrangement decays of S-wave $cs\bar{c}\bar{s}$ tetraquark states in a simplified quark model. The masses and widths are estimated by assuming that the $X(4140)$ is the lower $1^{++}$ $cs\bar{c}\bar{s}$ tetraquark. Comparing our results with experimental measurements, we find that the recently observed $X(3960)$ by LHCb can be assigned as the lowest $0^{++}$ $cs\bar{c}\bar{s}$ tetraquark state and the $X_0(4140)$ could be the second lowest $0^{++}$ $cs\bar{c}\bar{s}$ tetraquark. Predictions of ratios between partial widths for the involved tetraquarks are given. We call for searches for more $cs\bar{c}\bar{s}$ tetraquarks with $J^{PC}=1^{+-}$, $0^{++}$, and $2^{++}$., Comment: 1 figure

Analog physical neural networks, which hold promise for improved energy efficiency and speed compared to digital electronic neural networks, are nevertheless typically operated in a relatively high-power regime so that the signal-to-noise ratio (SNR) is large (>10). What happens if an analog system is instead operated in an ultra-low-power regime, in which the behavior of the system becomes highly stochastic and the noise is no longer a small perturbation on the signal? In this paper, we study this question in the setting of optical neural networks operated in the limit where some layers use only a single photon to cause a neuron activation. Neuron activations in this limit are dominated by quantum noise from the fundamentally probabilistic nature of single-photon detection of weak optical signals. We show that it is possible to train stochastic optical neural networks to perform deterministic image-classification tasks with high accuracy in spite of the extremely high noise (SNR ~ 1) by using a training procedure that directly models the stochastic behavior of photodetection. We experimentally demonstrated MNIST classification with a test accuracy of 98% using an optical neural network with a hidden layer operating in the single-photon regime; the optical energy used to perform the classification corresponds to 0.008 photons per multiply-accumulate (MAC) operation, which is equivalent to 0.003 attojoules of optical energy per MAC. Our experiment used >40x fewer photons per inference than previous state-of-the-art low-optical-energy demonstrations, to achieve the same accuracy of >90%. Our work shows that some extremely stochastic analog systems, including those operating in the limit where quantum noise dominates, can nevertheless be used as layers in neural networks that deterministically perform classification tasks with high accuracy if they are appropriately trained., Comment: 55 pages, 27 figures

The in-medium feature of nuclear force which includes both nucleon-nucleon ($NN$) and hyperon-nucleon ($\Lambda N$) interactions impacts the description of single-$\Lambda$ hypernuclei. With the alternated mass number or isospin of hypernuclei, such effects could be unveiled by analyzing systematical evolution of the bulk and single-particle properties. From a density-dependent meson-nucleon/hyperon coupling perspective, a new $\Lambda N$ effective interaction in the covariant density functional (CDF) theory, namely DD-LZ1-$\Lambda1$, is obtained by fitting the experimental data of $\Lambda$ separation energies for several single-$\Lambda$ hypernuclei. It is then adopted to study the structure and transition properties of single-$\Lambda$ hypernuclei in Oxygen isotopes, comparing with several selected CDF Lagrangians. Discrepancy is observed explicitly in the isospin evolution of $\Lambda1p$ spin-orbit splitting with various effective interactions, ascribed to their divergence of the meson-hyperon coupling strengths with increasing density. In particular, the density-dependent CDFs introduce an extra contribution to enhance the isospin dependence of the splitting, which is originated from the rearrangement terms of $\Lambda$ self-energies. In addition, the characteristics of hypernuclear radii are studied along the isotopic chain. Owing to the impurity effect of $\Lambda$ hyperon, a size shrinkage is observed in the matter radii of hypernuclei as compared to their cores of normal nuclei, while its magnitude is elucidated further to correlate with the incompressibility of nuclear matter. Besides, there exists a sizable model-dependent trend that $\Lambda$ hyperon radii evolve with the neutron number, which is decided partly by the in-medium $NN$ interactions as well as the core polarization effects., Comment: 15 pages, 5 figures, 3 tables

Assuming that the $P_c(4312)^+$ is a $I(J^P)=\frac12(\frac32^-)$ compact pentaquark, we study the mass spectrum of its S-wave hidden-charm partner states in a color-magnetic interaction model. Combining the information from their decays obtained in a simple rearrangement scheme, one finds that the quantum numbers of $P_c(4457)^+$, $ P_c(4440)^+$, and $P_c(4337)^+$ can be assigned to be $I(J^P)=\frac12(\frac32^-)$, $\frac12(\frac12^-)$, and $\frac12(\frac12^-)$, respectively, while both $P_{cs}(4338)^0$ and $P_{cs}(4459)^0$ can be interpreted as $I(J^P)=0(\frac12^-)$ $udsc\bar{c}$ compact states. Based on the numerical results, we also find narrow pentaquarks in $ssnc\bar{c}$ ($n=u,d$) and $sssc\bar{c}$ systems. The decay properties of the studied pentaquarks and the searching channels for them can be tested in future experiments., Comment: 17 pages, 14 tables, 4 figures

Decay amplitude of $H \to \gamma Z$ process via one $W$ loop in the unitary gauge is presented. The divergent integrals including those of high divergence orders typical of unitary gauge are arranged to cancel to get the electromagnetic $U(1)$ gauge invariant finite result, hence no contribution to the renormalization constant of $Z\gamma$ mixing in this 1-loop subprocess. For the calculation of the Feynman diagrams employing the Feynman rules, all the integrations of the propagator momenta and all the delta-functions representing the 4-momentum conservation of every vertex are retained in the beginning. Therefore, the ambiguity of setting independent loop momentum for divergences worse than logarithmic does not exist, and shift of integrated variable in such divergent integrals is eschewed. The calculation are done in 4-dimension Minkowski momentum space without the aid of any regularization. The correct treatment on the surface terms for the quadratic and logarithmic tensor integral is one of the key points. This part I is devoted to the calculation details and the indications from the key surface terms. Comparing with other gauge(s) and complete results for $H \to \gamma Z$ are left for part II., Comment: 29 pages, 3 figures. This paper is mainly for calculation details as ref. arXiv admin note: text overlap with arXiv:1705.04941