Miracle-dz/UniFAR-FTUs huggingface dataset:
Towards optimization of quantum circuits

Any unitary operation in quantum information processing can be implemented via a sequence of simpler steps — quantum gates. However, actual implementation of a quantum gate is always imperfect and takes a finite time. Therefore, searching for a short sequence of gates — efficient quantum circuit for a given operation, is an important task. We contribute to this issue by proposing optimization of the well-known universal procedure proposed by Barenco et al. [Phys. Rev. A 52, 3457 (1995)]. We also created a computer program which realizes both Barenco’s decomposition and the proposed optimization. Furthermore, our optimization can be applied to any quantum circuit containing generalized Toffoli gates, including basic quantum gate circuits.
Towards the infrared limit in SU(3) Landau gauge lattice gluodynamics

We study the behavior of the gluon and ghost dressing functions in SU(3) Landau gauge at low momenta available on lattice sizes 12{sup 4}-32{sup 4} at {beta}=5.8, 6.0 and 6.2. We demonstrate the ghost dressing function to be systematically dependent on the choice of Gribov copies, while the influence on the gluon dressing function is not resolvable. The running coupling given in terms of these functions is found to be decreasing for momenta q<0.6 GeV. We study also effects of the finite volume and of the lattice discretization.
The Formation and Evolution of Candidate Young Globular Clusters in NGC 3256

We present images of the recent galaxy merger NGC 3256 obtained with the Wide Field Planetary Camera 2 of the Hubble Space Telescope in B and I filters. We show that there is a large population of more than 1000 compact, bright, blue objects in this galaxy within the 7 kpc × 7 kpc region studied. These objects have sizes, colors, and luminosities like those expected for young Galactic globular clusters, with ages ranging from a few to several hundred megayears. On this basis, we identify at least some fraction of the compact, bright, blue objects in NGC 3256 as young globular clusters. The young cluster system makes up a significant fraction of the total luminosity of the galaxy within the region studied—15%–20% in B and half that in I, indicating a high efficiency of cluster formation on a galaxy-wide scale. In order to determine the properties of this young cluster system, the selection effects in size, color, and luminosity are carefully modeled. We find that the intrinsic color distribution is broad and there is no significant trend of color with magnitude. The combination of the broad range of observed colors and the lack of a trend of redder colors at fainter magnitudes cannot be fitted solely by a broad age distribution and/or differential reddening, although the latter is clearly present. The observations can be accounted for by either the preferential depletion/destruction of lower mass clusters as they age or a very young age (≲20 Myr) for the cluster population, comparable to or less than the dynamical time of the region in which the clusters are observed. We also find that the luminosity function of the young cluster system can be roughly fitted by a power law with an exponent of -1.8, with tentative evidence that it flattens at faint magnitudes. The clusters are compact in size, with typical estimated half-light radii of 5–10 pc, but there is no obvious cutoff for larger radii and only a shallow trend of size with luminosity. We discuss the implications of these results for models of the formation and dynamical evolution of globular clusters, as well as for interpretation of the properties of older globular cluster systems.
Rings of Low Multiplicative Complexity

The complexity of the multiplication operation in finite fields is of interest for both theoretical and practical reasons. For example, an optimal normal basis for F2N has complexity 2N? 1. A construction described in J. H. Silverman, (“Cryptographic Hardware and Embedded Systems,” Lecture Notes in Computer Science, Vol. 1717, pp. 122? 134, Springer? Verlag, Berlin, 1999.) allows multiplication of complexity N+1 to be performed in F2N by working in a larger ring R of dimension N+1 over F2. In this paper we give a complete classification of all such rings and show that this construction is the only one which also has a certain useful permutability property.
Einstein equations in the null quasi-spherical gauge III: numerical algorithms

We describe numerical techniques used in the construction of our 4th order evolution for the full Einstein equations, and assess the accuracy of representative solutions. The code is based on a null gauge with a quasi-spherical radial coordinate, and simulates the interaction of a single black hole with gravitational radiation. Techniques used include spherical harmonic representations, convolution spline interpolation and filtering, and an RK4 "method of lines" evolution. For sample initial data of "intermediate" size (gravitational field with 19% of the black hole mass), the code is accurate to 1 part in 10^5, until null time z=55 when the coordinate condition breaks down.
Success and Persistence in Science: The Influence of Classroom Climate

To better understand how student and faculty perceptions of the learning climate in science/mathematics classes influence success and persistence, we followed a cohort of 1425 academically able students who entered CEGEP in the fall of 2003. Students completed surveys in their first, second and fourth semesters. In the second semester 84 faculty members completed a similar survey. Faculty conceptions of teaching were identified using a framework developed by Scardamalia and Bereiter (1989). No significant gender differences in achievement were found. Self-efficacy declined over students first semester as did affect towards science. Classes that students perceived as fostering their development had a positive impact on persistence and success while classes characterized as transmitting had a negative impact. Females were more likely than males to characterize a class as transmitting and to abandon science. Faculty members who had pedagogical training were more likely to create a fostering atmosphere in their classes.
Collaborative Competition? A Great Way to Teach and Motivate

In my physics classes, I strive to motivate my students to do their very best work and inspire them to work harder than they have ever been asked to before. To reach that level, I find that my students need an outside motivation. They need to have someone from outside of their education community judge their skills and efforts. I have found that participation in team competitions provides students with the motivation to excel and also has the benefits of teaching students to work in a team setting. Thanks to several science-oriented organizations, there are a number of what I like to call “collaborative competitions” just begging for our students to enter, compete, and yes, even win! In this paper, I will describe some of the competitions my students have participated in and provide some tips for other teachers who may want to do likewise.
An Examination of Semantic Impairment in Amnestic MCI and AD: What Can We Learn From Verbal Fluency?

INTRODUCTION The Verbal Fluency Test (VF) is commonly used in neuropsychology. Some studies have demonstrated a marked impairment of semantic VF compared to phonemic VF in Alzheimer's disease (AD). Since amnestic Mild Cognitive Impairment (aMCI) is associated with increased risk of conversion to incident AD, it is relevant to examine whether a similar impairment is observed in this population. The objective of the present empirical study is to compare VF performance of aMCI patients to those of AD and elderly controls matched one-to-one for age and education. METHOD Ninety-six participants divided into three equal groups (N = 32: AD, aMCI and Controls) were included in this study. Participants in each group were, on average, 76 years of age and had 13 years of education. A repeated measures ANOVA with the Group (AD, aMCI, NC) as between-subject factor and the Fluency condition ("P" and "animals") as within-subject factor was performed. T-tests and simple ANOVAs were also conducted to examine the interaction. RESULTS There was a significant interaction between the groups and the verbal fluency condition. In AD, significantly fewer words were produced in both conditions. In contrast, participants with aMCI demonstrated a pattern similar to controls in the phonemic condition, but generated significantly fewer words in the semantic condition. CONCLUSION These results indicate a semantic memory impairment in aMCI revealed by a simple, commonly-used neuropsychological test. Future studies are needed to investigate if semantic fluency deficits can help predict future conversion to AD.
The relation between abundance gradients and the physical properties of spiral galaxies

Some correlations of the behaviour of chemical abundance gradients with other physical properties of spiral galaxies are established. The sample is some 30 galaxies for which good published spectrophotometry of H II regions is available. The central abundances of spirals are correlated with their mass, barred galaxies have shallow gradients, and non-barred spirals show a correlation of gradient slope with morphological type. The correlation of abundance with mass surface density is confirmed and there are indications that the effective yield may vary as a function of metallicity
Saddle-splay and mechanical instability in nematics confined to a cylindrical annular geometry

Abstract The occurrence of a mechanical instability is predicted for a nematic liquid crystal confined to a cylindrical annular geometry. The surfaces impose either a bend distortion (azimuthal configuration) or a splay distortion (radial configuration) in the plane of the cylinders′ cross-section. Remarkably, the instability appears also with strong anchoring, and, when the torsional anchoring is weak, then the saddle-splay elastic constant K24 deeply influences the critical radii.
Membrane and fivebrane instantons and quaternionic geometry

We investigate membrane and fivebrane instanton effects in type IIA string theory compactified on rigid Calabi-Yau manifolds. These effects contribute to the low-energy effective action of the universal hypermultiplet, in four dimensional spacetime. To compute the nonperturbative effects due to the fivebrane instanton to the universal hypermultiplet, an instanton calculation is performed. In the absence of fivebrane instantons, the quaternionic geometry of the hypermultiplet is determined by solutions of the threedimensional Toda equation. We construct solutions describing membrane instantons and find perfect agreement with string theory predictions. In the context of flux compactifications we discuss how membrane instantons contribute to the scalar potential and the stabilization of moduli. Finally, we demonstrate the existence of metastable de Sitter vacua.
Optimal focusing for maximal collection of entangled narrow-band photon pairs into single-mode fibers

We present a theoretical and experimental investigation of the emission characteristics and the flux of photon pairs generated by spontaneous parametric downconversion in quasi-phase matched bulk crystals for the use in quantum communication sources. We show that, by careful design, one can attain well defined modes close to the fundamental mode of optical fibers and obtain high coupling efficiencies also for bulk crystals, these being more easily aligned than crystal waveguides. We distinguish between singles coupling, ${\ensuremath{\gamma}}_{\mathrm{s}}$ and ${\ensuremath{\gamma}}_{\mathrm{i}}$, conditional coincidence, ${\ensuremath{\mu}}_{\mathrm{i}\ensuremath{\mid}\mathrm{s}}$, and pair coupling, ${\ensuremath{\gamma}}_{\mathrm{c}}$, and show how each of these parameters can be maximized by varying the focusing of the pump mode and the fiber-matched modes using standard optical elements. Specifically we analyze a periodically poled KTP-crystal pumped by a $532\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ laser creating photon pairs at $810\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ and $1550\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. Numerical calculations lead to coupling efficiencies above 93% at optimal focusing, which is found by the geometrical relation $L∕{z}_{R}$ to be $\ensuremath{\approx}1$ to 2 for the pump mode and $\ensuremath{\approx}2$ to 3 for the fiber-modes, where $L$ is the crystal length and ${z}_{R}$ is the Rayleigh-range of the mode-profile. These results are independent on $L$. By showing that the single-mode bandwidth decreases $\ensuremath{\propto}1∕L$, we can therefore design the source to produce and couple narrow bandwidth photon pairs well into the fibers. Smaller bandwidth means both less chromatic dispersion for long propagation distances in fibers, and that telecom Bragg gratings can be utilized to compensate for broadened photon packets\char22{}a vital problem for time-multiplexed qubits. Longer crystals also yield an increase in fiber photon flux $\ensuremath{\propto}\sqrt{L}$, and so, assuming correct focusing, we can only see advantages using long crystals.
The effect of ram pressure on the molecular gas of galaxies: three case studies in the Virgo cluster

We present 12CO (2-1) data of three Virgo spirals - NGC 4330, NGC 4402 and NGC 4522 obtained using the Submillimeter Array. These three galaxies show clear evidence of ram pressure stripping due to the cluster medium as found in previous HI imaging studies. Using high-resolution CO data, we investigate how the properties of the inner molecular gas disc change while a galaxy is undergoing HI stripping in the cluster. At given sensitivity limits, we do not find any clear signs of molecular gas stripping. However, both its morphology and kinematics appear to be quite disturbed as those of HI. Morphological peculiarities present in the molecular and atomic gas are closely related with each other, suggesting that molecular gas can be also affected by strong ICM pressure even if it is not stripped. CO is found to be modestly enhanced along the upstream sides in these galaxies, which may change the local star formation activity in the disc. Indeed, the distribution of H$\alpha$ emission, a tracer of recent star formation, well coincides with that of the molecular gas, revealing enhancements near the local CO peak or along the CO compression. FUV and H$\alpha$ share some properties in common, but FUV is always more extended than CO/H$\alpha$ in the three galaxies, implying that the star-forming disc is rapidly shrinking as the molecular gas properties have changed. We discuss how ICM pressure affects dense molecular gas and hence star formation properties while diffuse atomic gas is being removed from a galaxy.
New Evidence for the Dynamical Decay of a Multiple System in the Orion Kleinmann–Low Nebula

We have measured astrometry for members of the Orion Nebula Cluster with images obtained in 2015 with the Wide Field Camera 3 on board the Hubble Space Telescope. By comparing those data to previous measurements with the Near-Infrared Camera and Multi-Object Spectrometer on Hubble in 1998, we have discovered that a star in the Kleinmann–Low Nebula, source x from Lonsdale et al., is moving with an unusually high proper motion of 29 mas yr−1, which corresponds to 55 km s−1 at the distance of Orion. Previous radio observations have found that three other stars in the Kleinmann–Low Nebula (the Becklin–Neugebauer object and sources I and n) have high proper motions (5–14 mas yr−1) and were near a single location ∼540 years ago, and thus may have been members of a multiple system that dynamically decayed. The proper motion of source x is consistent with ejection from that same location 540 years ago, which provides strong evidence that the dynamical decay did occur and that the runaway star BN originated in the Kleinmann–Low Nebula rather than the nearby Trapezium cluster. However, our constraint on the motion of source n is significantly smaller than the most recent radio measurement, which indicates that it did not participate in the event that ejected the other three stars.
Galaxies in the Illustris simulation as seen by the Sloan Digital Sky Survey - II. Size-luminosity relations and the deficit of bulge-dominated galaxies in Illustris at low mass

The interpretive power of the newest generation of large-volume hydrodynamical simulations of galaxy formation rests upon their ability to reproduce the observed properties of galaxies. In this second paper in a series, we employ bulge+disc decompositions of realistic dust-free galaxy images from the Illustris simulation in a consistent comparison with galaxies from the Sloan Digital Sky Survey (SDSS). Examining the size-luminosity relations of each sample, we find that galaxies in Illustris are roughly twice as large and $0.7$ magnitudes brighter on average than galaxies in the SDSS. The trend of increasing slope and decreasing normalization of size-luminosity as a function of bulge-fraction is qualitatively similar to observations. However, the size-luminosity relations of Illustris galaxies are quantitatively distinguished by higher normalizations and smaller slopes than for real galaxies. We show that this result is linked to a significant deficit of bulge-dominated galaxies in Illustris relative to the SDSS at stellar masses $\log\mathrm{M}_{\star}/\mathrm{M}_{\odot}\lesssim11$. We investigate this deficit by comparing bulge fraction estimates derived from photometry \emph{and} internal kinematics. We show that photometric bulge fractions are systematically lower than the kinematic fractions at low masses, but with increasingly good agreement as the stellar mass increases.
The M 101 group complex: new dwarf galaxy candidates and spatial structure

Context. The fine details of the large-scale structure in the local Universe provide important empirical benchmarks for testing cosmological models of structure formation. Dwarf galaxies are key object for such studies. Aims. Our aim was to enlarge the sample of known dwarf galaxies in the local Universe. We performed a search for faint unresolved low-surface-brightness dwarf galaxies in the M 101 group complex, including the region around the major spiral galaxies M 101, M 51, and M 63 lying at a distance of 7.0, 8.6, and 9.0 Mpc, respectively. The new dwarf galaxy sample can be used in a first step to test for significant substructure in the 2D distribution and in a second step to study the spatial distribution of the galaxy complex. Methods. Using filtering algorithms we surveyed 330 square degrees of imaging data obtained from the Sloan Digital Sky Survey. The images were visually inspected. The spatial distribution of known galaxies and candidates was analyzed and the system transformed into a M 101 eigenframe using the geometrical alignment of the group. Results. We discovered 15 new dwarf galaxies and carried out surface photometry in the g and r bands. The similarity of the photometric properties of these dwarfs to those of Local Group dwarfs suggest membership to the M 101 group complex. The sky distribution of the candidates follows the thin planar structure outlined by the known members of the three subgroups. The ~3 Mpc long filamentary structure has a rms thickness of 67 kpc. The planar structure of the embedded M 101 subgroup is even thinner, with rms = 46 kpc. The formation of this structure might be due to the expansion of the bordering Local Void. Other implications are discussed as well. Conclusions. We show the viability of SDSS data to extend the sample of dwarfs in the local Universe and test cosmological models on small scales.
Sheath-accumulating Propagation of Interplanetary Coronal Mass Ejection

Fast interplanetary coronal mass ejections (ICMEs) are the drivers of strong space weather storms such as solar energetic particle events and geomagnetic storms. The connection between the space-weather-impacting solar wind disturbances associated with fast ICMEs at Earth and the characteristics of causative energetic CMEs observed near the Sun is a key question in the study of space weather storms, as well as in the development of practical space weather prediction. Such shock-driving fast ICMEs usually expand at supersonic speeds during the propagation, resulting in the continuous accumulation of shocked sheath plasma ahead. In this paper, we propose a “sheath-accumulating propagation” (SAP) model that describes the coevolution of the interplanetary sheath and decelerating ICME ejecta by taking into account the process of upstream solar wind plasma accumulation within the sheath region. Based on the SAP model, we discuss (1) ICME deceleration characteristics; (2) the fundamental condition for fast ICMEs at Earth; (3) the thickness of interplanetary sheaths; (4) arrival time prediction; and (5) the super-intense geomagnetic storms associated with huge solar flares. We quantitatively show that not only the speed but also the mass of the CME are crucial for discussing the above five points. The similarities and differences between the SAP model, the drag-based model, and the“snow-plow” model proposed by Tappin are also discussed.
The MASIV Survey - IV. Relationship between intra-day scintillation and intrinsic variability of radio AGNs

We investigate the relationship between 5 GHz interstellar scintillation (ISS) and 15 GHz intrinsic variability of compact, radio-selected AGNs drawn from the Microarcsecond Scintillation-Induced Variability (MASIV) Survey and the Owens Valley Radio Observatory (OVRO) blazar monitoring program. We discover that the strongest scintillators at 5 GHz (modulation index, $m_5 \geq 0.02$) all exhibit strong 15 GHz intrinsic variability ($m_{15} \geq 0.1$). This relationship can be attributed mainly to the mutual dependence of intrinsic variability and ISS amplitudes on radio core compactness at $\sim 100\, \mu$as scales, and to a lesser extent, on their mutual dependences on source flux density, arcsec-scale core dominance and redshift. However, not all sources displaying strong intrinsic variations show high amplitude scintillation, since ISS is also strongly dependent on Galactic line-of-sight scattering properties. This observed relationship between intrinsic variability and ISS highlights the importance of optimizing the observing frequency, cadence, timespan and sky coverage of future radio variability surveys, such that these two effects can be better distinguished to study the underlying physics. For the full MASIV sample, we find that Fermi-detected gamma-ray loud sources exhibit significantly higher 5 GHz ISS amplitudes than gamma-ray quiet sources. This relationship is weaker than the known correlation between gamma-ray loudness and the 15 GHz variability amplitudes, most likely due to jet opacity effects.