ShantanuT01/DACTYL-Pretraining huggingface dataset:
We report on the usage of a linear optics phase gate for distinguishing all four Bell states simultaneously in a quantum teleportation and entanglement swapping protocol. This is demonstrated by full state tomography of the one and two qubit output states of the two protocols, yielding average state fidelities of about 0.83 and 0.77, respectively. In addition, the performance of the teleportation channel is characterised by quantum process tomography. The non classical properties of the entanglement swapping output states are further confirmed by the violation of a CHSH-type Bell inequality of 2.14 on average.
Applying Stein's method, an inductive technique and size bias coupling yields a Berry-Esseen theorem for normal approximation without the usual restriction that the coupling be bounded. The theorem is applied to counting the number of vertices in the Erdos-Renyi random graph of a given degree.
We use hydrodynamical simulations from the OWLS project to investigate the dependence of the physical properties of galaxy populations at redshift 2 on the assumed star formation law, the equation of state imposed on the unresolved interstellar medium, the stellar initial mass function, the reionization history, and the assumed cosmology. This work complements that of Paper I, where we studied the effects of varying models for galactic winds driven by star formation and AGN. The normalisation of the matter power spectrum strongly affects the galaxy mass function, but has a relatively small effect on the physical properties of galaxies residing in haloes of a fixed mass. Reionization suppresses the stellar masses and gas fractions of low-mass galaxies, but by z = 2 the results are insensitive to the timing of reionization. The stellar initial mass function mainly determines the physical properties of galaxies through its effect on the efficiency of the feedback, while changes in the recycled mass and metal fractions play a smaller role. If we use a recipe for star formation that reproduces the observed star formation law independently of the assumed equation of state of the unresolved ISM, then the latter is unimportant. The star formation law, i.e. the gas consumption time scale as a function of surface density, determines the mass of dense, star-forming gas in galaxies, but affects neither the star formation rate nor the stellar mass. This can be understood in terms of self-regulation: the gas fraction adjusts until the outflow rate balances the inflow rate.
Full shell-model diagonalization has been performed to study the structure of neutron-rich nuclei around $^{20}$C. We investigate in detail the roles played by the different monopole components of the effective interaction in the evolution of the N=14 shell in C, N and O isotopes. It is found that the relevant neutron-neutron monopole terms, $V^{nn}_{d_{5/2}d_{5/2}}$ and $V^{nn}_{s_{1/2}s_{1/2}}$, contribute significantly to the reduction of the N=14 shell gap in C and N isotopes in comparison with that in O isotopes. The origin of this unexpectedly large effect, which is comparable with (sometimes even larger than) that caused by the proton-neutron interaction, is related to the enhanced configuration mixing in those nuclei due to many-body correlations. Such a scheme is also supported by the large B(E2) value in the nucleus $^{20}$C which has been measured recently.
We present a new method for determining the age of late-K type pre-main sequence (PMS) stars by deriving their surface gravity from high-resolution I-band spectroscopy. Since PMS stars contract as they evolve, age can be estimated from surface gravity. We used the equivalent width ratio (EWR) of nearby absorption lines to create a surface gravity diagnostic of PMS stars that is free of uncertainties due to veiling. The ratios of Fe (818.67nm and 820.49nm) and Na (818.33nm and 819.48nm) absorption lines were calculated for giants, main-sequence stars, and weak-line T Tauri stars. Effective temperatures were nearly equal across the sample. The Fe to Na EWR (Fe/Na) decreases significantly with increasing surface gravity, denoting that Fe/Na is a desirable diagnostic for deriving the surface gravity of pre-main sequence stars. The surface gravity of PMS stars with 0.8 solar mass is able to be determined with an accuracy of 0.1-0.2, which conducts the age of PMS stars within a factor of 1.5, in average.
Matter radii of the $^{34-40}$Mg nuclei are investigated by self-consistent Hartree-Fock-Bogolyubov calculations assuming the axial symmetry. With the semi-realistic M3Y-P6 interaction, the $N$-dependence of the matter radii observed in the experiments is reproduced excellently. Both the pairing and the deformation play significant roles in an intertwined manner. The $^{35}$Mg nucleus has a smaller radius than the neighboring even-$N$ nuclei, which is attributed to its smaller deformation. In contrast, a neutron halo is obtained in $^{37}$Mg. We point out that, in contrast to the pairing anti-halo effect that may operate on the even-$N$ nuclei, the pair correlation enhances halos in odd-$N$ nuclei, owing to the new mechanism which we call \textit{unpaired-particle haloing}. The halo in $^{37}$Mg is predicted to have peanut shape in its intrinsic state, reflecting $p$-wave contribution, as in $^{40}$Mg. The $N$-dependence of the deformation is significant again, by which the single-particle level dominated by the $p$-wave component comes down.
We study light pseudoscalar and axial states using a soft wall model that is modified by introducing two extra parameters: an UV-cutoff and an anomalous term in the conformal dimension of the fields involved such that meson fields with different parities are easily distinguishable. We find that 23 of these light mesonic states, including the scalars and vector states analyzed with one of our previous results, are fitted within the RMS error bounds given for this model, whose parameters are given by the quadratic dilaton profile, the UV locus $z_{0}$ and the anomalous term $\Delta_{P}$. Our results show that Regge trajectories for pseudoscalar and axial mesons are linear in the radial quantum number $n$, as expected for these sort of regular $q\overline{q}$ mesons.
We study relative log canonical pairs with relatively trivial log canonical divisors. We fix such a pair $(X,\Delta)/Z$ and establish the minimal model theory for the pair $(X,\Delta)$ assuming the minimal model theory for all Kawamata log terminal pairs whose dimension is not greater than ${\rm dim}\,Z$. We also show the finite generation of log canonical rings for log canonical pairs of dimension five which are not of log general type.
We investigate the potential of a restricted Boltzmann Machine (RBM) for discriminative representation learning. By imposing the class information preservation constraints on the hidden layer of the RBM, we propose a Signed Laplacian Restricted Boltzmann Machine (SLRBM) for supervised discriminative representation learning. The model utilizes the label information and preserves the global data locality of data points simultaneously. Experimental results on the benchmark data set show the effectiveness of our method.
Face detection is one of the challenging tasks in computer vision. Human face detection plays an essential role in the first stage of face processing applications such as face recognition, face tracking, image database management, etc. In these applications, face objects often come from an inconsequential part of images that contain variations, namely different illumination, poses, and occlusion. These variations can decrease face detection rate noticeably. Most existing face detection approaches are not accurate, as they have not been able to resolve unstructured images due to large appearance variations and can only detect human faces under one particular variation. Existing frameworks of face detection need enhancements to detect human faces under the stated variations to improve detection rate and reduce detection time. In this study, an enhanced face detection framework is proposed to improve detection rate based on skin color and provide a validation process. A preliminary segmentation of the input images based on skin color can significantly reduce search space and accelerate the process of human face detection. The primary detection is based on Haar-like features and the Adaboost algorithm. A validation process is introduced to reject non-face objects, which might occur during the face detection process. The validation process is based on two-stage Extended Local Binary Patterns. The experimental results on the CMU-MIT and Caltech 10000 datasets over a wide range of facial variations in different colors, positions, scales, and lighting conditions indicated a successful face detection rate.
Many new and unidentified Galactic sources have recently been revealed by ongoing hard X-ray surveys. A significant fraction of these have been shown to be the type of accreting white dwarfs known as cataclysmic variables (CVs). Follow-up observations are often required to categorize and classify these sources, and may also identify potentially unique or interesting cases. One such case is IGR J18007-4146, which is likely a CV based on follow-up Chandra observations and constraints from optical/IR catalogs. Utilizing simultaneous XMM-Newton and NuSTAR observations, as well as the available optical/IR data, we confirm the nature of IGR J18007-4146 as an intermediate polar type CV. Timing analysis of the XMM data reveals a periodic signal at 424.4 +/- 0.7 s that we interpret as the spin period of the white dwarf. Modeling the 0.3-78 keV spectrum, we use a thermal bremsstrahlung continuum but require intrinsic absorption as well as a soft component and strong Fe lines between 6 and 7 keV. We model the soft component using a single-temperature blackbody with kT = 73 +8/-6 eV. From the X-ray spectrum, we are able to measure the mass of the white dwarf to be 1.06 +0.19/-0.10 Msun, which means IGR J18007-4146 is more massive than the average for magnetic CVs.
We present observations of microlensing event MACHO-98-BLG-35 which reached a peak magnification factor of almost 80. These observations by the Microlensing Planet Search (MPS) and the MOA Collaborations place strong constraints on the possible planetary system of the lens star and show intriguing evidence for a low mass planet with a mass fraction $4\times 10^{-5} \leq \epsilon \leq 2\times 10^{-4}$. A giant planet with $\epsilon = 10^{-3}$ is excluded from 95% of the region between 0.4 and 2.5 $R_E$ from the lens star, where $R_E$ is the Einstein ring radius of the lens. This exclusion region is more extensive than the generic "lensing zone" which is $0.6 - 1.6 R_E$. For smaller mass planets, we can exclude 57% of the "lensing zone" for $\epsilon = 10^{-4}$ and 14% of the lensing zone for $\epsilon = 10^{-5}$. The mass fraction $\epsilon = 10^{-5}$ corresponds to an Earth mass planet for a lensing star of mass $\sim 0.3 \msun$. A number of similar events will provide statistically significant constraints on the prevalence of Earth mass planets. In order to put our limits in more familiar terms, we have compared our results to those expected for a Solar System clone averaging over possible lens system distances and orientations. We find that such a system is ruled out at the 90% confidence level. A copy of the Solar System with Jupiter replaced by a second Saturn mass planet can be ruled out at 70% confidence. Our low mass planetary signal (few Earth masses to Neptune mass) is significant at the $4.5\sigma$ confidence level. If this planetary interpretation is correct, the MACHO-98-BLG-35 lens system constitutes the first detection of a low mass planet orbiting an ordinary star without gas giant planets.
We investigate the serendipitous X-ray source population revealed in XMM-Newton observations targeted in the Galactic Plane within the region 315<l<45 and |b|<2.5 deg. Our study focuses on a sample of 2204 X-ray sources at intermediate to faint fluxes, which were detected in a total of 116 XMM fields and are listed in the 2XMMi catalogue. We characterise each source as spectrally soft or hard on the basis of whether the bulk of the recorded counts have energies below or above 2 keV and find that the sample divides roughly equally (56%:44%) into these soft and hard categories. The X-ray spectral form underlying the soft sources may be represented as either a power-law continuum with Gamma~2.5 or a thermal spectrum with kT~0.5 keV, with N_H ranging from 10^{20-22} cm^{-2}. For the hard sources, a significantly harder continuum form is likely, i.e., Gamma~1 with N_H=10^{22-24} cm^{-2}. For ~50% of the hard sources, the inferred column density is commensurate with the total Galactic line-of-sight value; many of these sources will be located at significant distances across the Galaxy implying a hard band luminosity L_X>10^{32} erg/s, whereas some will be extragalactic interlopers. >90% of the soft sources have potential NIR (2MASS and/or UKIDSS) 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 cutoff which corresponds to the saturation of the X-ray coronal emission at L_X=10^{-3} L_{bol}. In contrast, the success rate in finding likely IR counterparts to the hard X-ray sample is no more than ~15% down to J=16 and ~25% 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.
We discuss the "exhaustion" problem in the context of the Periodic Anderson Model using Iterated Perturbation Theory(IPT) within the Dynamical Mean Field Theory. We find that, despite its limitations, IPT captures the exhaustion physics, which manifests itself as a dramatic, strongly energy dependent suppression of the effective Anderson impurity problem. As a consequence, low energy scales in the lattice case are strongly suppressed compared to the "Kondo scale" in the single-impurity picture. The IPT results are in qualitative agreement with recent Quantum Monte Carlo results for the same problem.
The Jarzynski Equality relates the free energy difference between two equilibrium states of a system to the average of the work over all irreversible paths to go from one state to the other. We claim that the derivation of this equality is flawed, introducing an ad hoc and unjustified weighting factor which handles improperly the heat exchange with a heat bath. Therefore Liphardt et al's experiment cannot be viewed as a confirmation of this equality, although the numerical deviations between the two are small. However, the Jarzynski Equality may well be a useful approximation, e.g. in measurements on single molecules in solution.
We study the critical behavior of surface-interacting self-avoiding random walks on a class of truncated simplex lattices, which can be labeled by an integer $n\ge 3$. Using the exact renormalization group method we have been able to obtain the exact values of various critical exponents for all values of n up to n=6. We also derived simple formulas which describe the asymptotic behavior of these exponents in the limit of large n ($n\to\infty$). In spite of the fact that the coordination number of the lattice tends to infinity in this limit, we found that the most of the studied critical exponents approach certain finite values, which differ from corresponding values for simple random walks (without self-avoiding walk constraint).
Electrical current-induced deterministic magnetization switching in a magnetic multilayer structure without external magnetic field is realized by utilizing interlayer exchange coupling. Two ferromagnetic Co layers, with in-plane and out-of-plane anisotropy respectively, are separated by a spacer Ta layer, which plays a dual role of inducing antiferromagnetic interlayer coupling, and contributing to the current-induced effective magnetic field through the spin Hall effect. The current-induced magnetization switching behavior can be tuned by pre-magnetizing the in-plane Co layer. The antiferromagnetic exchange coupling field increases with decreasing thickness of the Ta layer, reaching 630+-5 Oe for a Ta thickness of 1.5nm. The magnitude of the current-induced perpendicular effective magnetic field from spin-orbit torque is 9.2 Oe/(107Acm-2). The large spin Hall angle of Ta, opposite in sign to that of Pt, results in a low critical current density of 9*10^6A/cm^2. This approach is promising for the electrical switching of magnetic memory elements without external magnetic field.
The multiwavelength observation of the nearby radio galaxy M87 provides a unique opportunity to study in detail processes occurring in Active Galactic Nuclei from radio waves to TeV gamma-rays. Here we report the detection of gamma-ray emission above 250 GeV from M87 in spring 2007 with the VERITAS atmospheric Cherenkov telescope array and discuss its correlation with the X-ray emission. The gamma-ray emission is measured to be point-like with an intrinsic source radius less than 4.5 arcmin. The differential energy spectrum is fitted well by a power-law function: dPhi/dE=(7.4+-1.3_{stat}+-1.5_{sys})(E/TeV)^{-2.31+-0.17_{stat}+-0.2_{sys}} 10^{-9}m^{-2}s^{-1}TeV^{-1}. We show strong evidence for a year-scale correlation between the gamma-ray flux reported by TeV experiments and the X-ray emission measured by the ASM/RXTE observatory, and discuss the possible short-time-scale variability. These results imply that the gamma-ray emission from M87 is more likely associated with the core of the galaxy than with other bright X-ray features in the jet.
Since convolutional neural network(CNN)models emerged,several tasks in computer vision have actively deployed CNN models for feature extraction. However,the conventional CNN models have a high computational cost and require high memory capacity, which is impractical and unaffordable for commercial applications such as real-time on-road object detection on embedded boards or mobile platforms. To tackle this limitation of CNN models, this paper proposes a wide-residual-inception (WR-Inception) network, which constructs the architecture based on a residual inception unit that captures objects of various sizes on the same feature map, as well as shallower and wider layers, compared to state-of-the-art networks like ResNet. To verify the proposed networks, this paper conducted two experiments; one is a classification task on CIFAR-10/100 and the other is an on-road object detection task using a Single-Shot Multi-box Detector(SSD) on the KITTI dataset.
In the era of noisy-intermediate-scale quantum computers, we expect to see quantum devices with increasing numbers of qubits emerge in the foreseeable future. To practically run quantum programs, logical qubits have to be mapped to the physical qubits by a qubit allocation algorithm. However, on present day devices, qubits differ by their error rate and connectivity. Here, we establish and demonstrate on current experimental devices a new allocation algorithm that combines the simulated annealing method with local search of the solution space using Dijkstra's algorithm. Our algorithm takes into account the weighted connectivity constraints of both the quantum hardware and the quantum program being compiled. New quantum programs will enable unprecedented developments in physics, chemistry, and materials science and our work offers an important new pathway toward optimizing compilers for quantum programs.
A broad effort is underway to improve the sensitivity of nuclear magnetic resonance through the use of dynamic nuclear polarization. Nitrogen-vacancy (NV) centers in diamond offer an appealing platform because these paramagnetic defects can be optically polarized efficiently at room temperature. However, work thus far has been mainly limited to single crystals because most polarization transfer protocols are sensitive to misalignment between the NV and magnetic field axes. Here we study the spin dynamics of NV-13C pairs in the simultaneous presence of optical excitation and microwave frequency sweeps at low magnetic fields. We show that a subtle interplay between illumination intensity, frequency sweep rate, and hyperfine coupling strength leads to efficient, sweep-direction-dependent 13C spin polarization over a broad range of orientations of the magnetic field. In particular, our results strongly suggest that finely-tuned, moderately coupled nuclear spins are key to the hyperpolarization process, which makes this mechanism distinct from other known dynamic polarization channels. These findings pave the route to applications where powders are intrinsically advantageous, including the hyper-polarization of target fluids in contact with the diamond surface or the use of hyperpolarized particles as contrast agents for in-vivo imaging.
We prove more precisely the following main result of \cite{Isk1}. There is two non-conjugate embeddings of $S_3\times \ZZ_2$ into the Cremona group that is given by the linear action of this group on the plane and the action on the two-dimensional torus.
Absorption lines with high blue-shifted velocities are frequently found in the ultraviolet (UV) and X-ray spectra of luminous active galactic nuclei (AGNs). This implies that high-velocity winds/outflows are common in AGNs. In order to study the formation of high-velocity winds, especially ultrafast outflows (UFOs), we perform two-dimensional magnetohydrodynamic (MHD) simulations. Initially, a magnetic field is set to be weaker than the gas pressure at the disk surface. In our simulations, line force operates on the region like filaments because the X-ray radiation from corona is shielded by dense gas in the inner region at some angle. The location of filaments changes with time and then the line-driven winds are exposed to X-ray and become highly ionized. The line force at the UV bands does not directly drive the highly ionized winds. In the sense of time average, the properties of high-velocity winds meet the formation condition of UFOs. Compared with line force, the function of magnetic field is negligible in directly driving winds. In the MHD model, the region around the rotational axis becomes magnetic-pressure dominated, which prevents gases from spreading to higher latitudes and then enhances the gas column density at middle and low latitudes (20$^{\rm o}$--70$^{\rm o}$). Higher column density is helpful to shield X-ray photons, which causes the line force to be more effective in the MHD model than in the hydrodynamic model. Higher-velocity winds with a broader opening angle are produced in the MHD model.
We propose a scheme for determining a generalised scaling function, namely the Sudakov factor in a peculiar double scaling limit for high spin and large twist operators belonging to the $sl(2)$ sector of planar ${\cal N}=4$ SYM. In particular, we perform explicitly the all-order computation at strong 't Hooft coupling regarding the first (contribution to the) generalised scaling function. Moreover, we compare our asymptotic results with the numerical solutions finding a very good agreement and evaluate numerically the non-asymptotic contributions. Eventually, we illustrate the agreement and prediction on the string side.