Miracle-dz/UniFAR-FTUs huggingface dataset:
Cosmology with a spin

Using the chiral representation for spinors we present a particularly transparent way to generate the most general spinor dynamics in a theory where gravity is ruled by the Einstein-Cartan-Holst action. In such theories torsion need not vanish, but it can be reinterpreted as a four-fermion self-interaction within a torsion-free theory. The self-interaction may or may not break parity invariance, and may contribute positively or negatively to the energy density, depending on the couplings considered. We then examine cosmological models ruled by a spinorial field within this theory. We find that while there are cases for which no significant cosmological novelties emerge, the self-interaction can also turn a mass potential into an upside-down Mexican hat potential. Then, as a general rule, the model leads to cosmologies with a bounce, for which there is a maximal energy density, and where the cosmic singularity has been removed. These solutions are stable, and range from the very simple to the very complex.
Redshift constraints for RGB 0136+391 and PKS 0735+178 from deep optical imaging

We present the results of deep I-band imaging of two BL Lacerate objects, RGB 0136+391 and PKS 0735+178, during an epoch when the optical nucleus was in a faint state in both targets. In PKS 0735+178 we find a significant excess over a point source, which, if fitted by the de Vaucouleurs model, corresponds to a galaxy with I = 18.64 +- 0.11 and r_eff = 1.8 +- 0.4 arcsec. Interpreting this galaxy as the host galaxy of PKS 0735+178 we derive z = 0.45 +- 0.06 using the host galaxy as a "standard candle". We also discuss the immediate optical environment of PKS 0735+178 and the identity of the MgII absorber at z = 0.424. Despite of the optimally chosen epoch and deep imaging we find the surface brightness profile of RGB 0136+391 to be consistent with a point source. By determining a lower limit for the host galaxy brightness by simulations, we derive z > 0.40 for this target.
TESTS OF THE EINSTEIN EQUIVALENCE PRINCIPLE USING TeV BLAZARS

The observed time delays between different energy bands from TeV blazars provide a new, interesting way of testing the Einstein Equivalence Principle (EEP). If the whole time delay is assumed to be dominated by the gravitational field of the Milky Way, the conservative upper limit on the EEP can be estimated. Here, we show that the strict limits on the differences of the parameterized post-Newtonian parameter γ values are γ TeV − γ keV < 3.86 × 10 − 3 ? > for Mrk 421 and γ TeV − γ keV < 4.43 × 10 − 3 ? > for Mrk 501, while expanding the scope of the tested EEP energy range out to the TeV–keV range for the first time. With the small time lag from the 0.2–0.8 TeV and >0.8 TeV light curves of PKS 2155-304, a much more severe constraint on γ differences of ∼10−6 can be achieved, although the energy difference is of the order of ∼TeV. Furthermore, we can combine these limits on the energy dependence of γ with the bound on the absolute γ value γ − 1 ∼ 0.3 % ? > from light deflection measurements at the optical (eV) bands, and conclude that this absolute bound on γ can be extended from optical to TeV energies.
Audit Tenure, Audit Firm Reputation and Audit Quality Study on Indonesian Manufacture Companies

The debate on audit quality still continues due to different results and arguments on audit tenure, audit firm reputation and audit quality. This study provides empirical evidence on the differentiation of audit quality by considering the audit tenure and audit firm reputation. Using the data from IDX of manufacturing companies in 2019 and 2020, the researcher examines the difference in audit quality, measured by discretionary accruals, in terms of audit tenure and audit firm reputation. This study also examines 247 companies that are analyzed using Mann-Whitney test. Findings from this study reveal that there is no significant difference between the audit quality of companies that have repeated and non-repeated audits. However, this study indicates that there is a significant difference in the audit quality of a company that is audited by the big 4 and non-big 4 audit firms. Based on the result, it can be suggested that auditor rotation is not necessary to enhance the audit quality since independent auditors tend to sustain their reputation and maintain their service qualifications.
Haagerup approximation property and positive cones associated with a von Neumann algebra

We introduce the notion of the $\alpha$-Haagerup approximation property for $\alpha\in[0,1/2]$ using a one-parameter family of positive cones studied by Araki and show that the $\alpha$-Haagerup approximation property actually does not depend on a choice of $\alpha$. This gives us a direct proof of the fact that two characterizations of the Haagerup approximation property are equivalent, one in terms of the standard form and the other in terms of completely positive maps. We also discuss the $L^p$-Haagerup approximation property for a non-commutative $L^p$-spaces associated with a von Neumann algebra ($1<p<\infty$) and show the independency of the $L^p$-Haagerup approximation property on $p$.
On the convergence rate of Galerkin approximations for the magnetohydrodynamic type equations

The motion of incompressible electrical conducting fluids can be modeled by magnetohydrodynamics equations, which consider the Navier-Stokes equations coupled with Maxwell’s equations. For the classical Navier-Stokes system, there exists an extensively study of the convergence rate for the Galerkin approximations. In this work, we extend the estimates rates of spectral Galerkin approximations for Navier–Stokes equations to the magnetohydrodynamic equations. We prove optimal error estimates in the L 2 (Ω) and H 1 (Ω) –norms and obtain a result similar to that one of Rautmann for the H 2 (Ω) –norm for the Navier–Stokes case. In this sense, we reach basically the same level of knowledge as in the case of the classical Navier-Stokes.
HOMOLOGICAL DIMENSIONS OF CROSSED PRODUCTS

Abstract In this paper, we consider several homological dimensions of crossed products A α σ G, where A is a left Noetherian ring and G is a finite group. We revisit the induction and restriction functors in derived categories, generalizing a few classical results for separable extensions. The global dimension and finitistic dimension of A σ α G are classified: global dimension of A σ α G is either infinity or equal to that of A, and finitistic dimension of A σ α G coincides with that of A. A criterion for skew group rings to have finite global dimensions is deduced. Under the hypothesis that A is a semiprimary algebra containing a complete set of primitive orthogonal idempotents closed under the action of a Sylow p-subgroup S ≤ G, we show that A and A α σ G share the same homological dimensions under extra assumptions, extending the main results in (Li, Representations of modular skew group algebras, Trans. Amer. Math. Soc. 367(9) (2015), 6293–6314, Li, Finitistic dimensions and picewise hereditary property of skew group algebras, to Glasgow Math. J. 57(3) (2015), 509–517).
A SYSTEMATIC SURVEY OF PROTOCLUSTERS AT z ∼ 3–6 IN THE CFHTLS DEEP FIELDS

We present the discovery of three protoclusters at z ∼ 3–4 with spectroscopic confirmation in the Canada–France–Hawaii Telescope Legacy Survey Deep Fields. In these fields, we investigate the large-scale projected sky distribution of z ∼ 3–6 Lyman-break galaxies and identify 21 protocluster candidates from regions that are overdense at more than 4σ overdensity significance. Based on cosmological simulations, it is expected that more than 76% of these candidates will evolve into a galaxy cluster of at least a halo mass of 1014 M⊙ at z = 0. We perform follow-up spectroscopy for eight of the candidates using Subaru/FOCAS, Keck II/DEIMOS, and Gemini-N/GMOS. In total we target 462 dropout candidates and obtain 138 spectroscopic redshifts. We confirm three real protoclusters at z = 3–4 with more than five members spectroscopically identified and find one to be an incidental overdense region by mere chance alignment. The other four candidate regions at z ∼ 5–6 require more spectroscopic follow-up in order to be conclusive. A z = 3.67 protocluster, which has 11 spectroscopically confirmed members, shows a remarkable core-like structure composed of a central small region (<0.5 physical Mpc) and an outskirts region (∼1.0 physical Mpc). The Lyα equivalent widths of members of the protocluster are significantly smaller than those of field galaxies at the same redshift, while there is no difference in the UV luminosity distributions. These results imply that some environmental effects start operating as early as at z ∼ 4 along with the growth of the protocluster structure. This study provides an important benchmark for our analysis of protoclusters in the upcoming Subaru/HSC imaging survey and its spectroscopic follow-up with the Subaru/PFS that will detect thousands of protoclusters up to z ∼ 6.
Twisted-light-induced optical transitions in semiconductors: Free-carrier quantum kinetics

We theoretically investigate the interband transitions and quantum kinetics induced by light carrying orbital angular momentum, or twisted light, in bulk semiconductors. We pose the problem in terms of the Heisenberg equations of motion of the electron populations, and interband and intraband coherences. Our theory extends the free-carrier semiconductor Bloch equations to the case of photoexcitation by twisted light. The theory is formulated using cylindrical coordinates, which are better suited to describe the interaction with twisted light than the usual Cartesian coordinates used to study regular optical excitation. We solve the equations of motion in the low excitation regime, and obtain analytical expressions for the coherences and populations; with these, we calculate the orbital angular momentum transferred from the light to the electrons and the paramagnetic and diamagnetic electric current densities.
THE NEW ECLIPSING CV MASTER OTJ192328.22+612413.5—A POSSIBLE SW SEXTANTIS STAR

We present optical photometry and spectroscopy of the new eclipsing cataclysmic variable MASTER OTJ192328.22+612413.5, discovered by the MASTER team. We find the orbital period to be P = 0.16764612(5) day/4.023507(1) hr. The depth of the eclipse (2.9 ± 0.1 mag) suggests that the system is nearly edge on, and modeling of the system confirms the inclination to be between 81. °3 and 83. °6. The brightness outside the eclipse varies between observations, with a change of 1.6 ± 0.1 mag. Spectroscopy reveals double-peaked Balmer emission lines. By using spectral features matching a late M-type companion, we bound the distance to be 750 ± 250 pc, depending on the companion’s spectral type. The source displays 2 mag brightness changes on timescales of days. The amplitude of these changes, along with the spectrum at the faint state, suggest that the system is possibly a dwarf nova. The lack of any high-excitation He ii lines suggests that this system is not magnetically dominated. The light curve in both quiescence and outburst resembles that of Lanning 386, implying MASTER OTJ192328.22+612413.5 is a possible cross between a dwarf nova and a SW Sextantis star.
Stability of Wafer-Scale Thin Films of Vertically Aligned Hexagonal BN Nanosheets Exposed to High-Energy Ions and Reactive Atomic Oxygen

Stability of advanced functional materials subjected to extreme conditions involving ion bombardment, radiation, or reactive chemicals is crucial for diverse applications. Here we demonstrate the excellent stability of wafer-scale thin films of vertically aligned hexagonal BN nanosheets (hBNNS) exposed to high-energy ions and reactive atomic oxygen representative of extreme conditions in space exploration and other applications. The hBNNS are fabricated catalyst-free on wafer-scale silicon, stainless steel, copper and glass panels at a lower temperature of 400 °C by inductively coupled plasma (ICP) assisted chemical vapor deposition (CVD) and subsequently characterized. The resistance of BNNS to high-energy ions was tested by immersing the samples into the plasma plume at the anode of a 150 W Hall Effect Thruster with BNNS films facing Xenon ions, revealing that the etching rate of BNNS is 20 times less than for a single-crystalline silicon wafer. Additionally, using O2/Ar/H2 plasmas to simulate the low Earth orbit (LEO) environment, it is demonstrated that the simulated plasma had very weak influence on the hBNNS surface structure and thickness. These results validate the strong potential of BNNS films for applications as protective, thermally conductive and insulating layers for spacecrafts, electric plasma satellite thrusters and semiconductor optoelectronic devices.
Long-term evolution of three-planet systems to the post-main sequence and beyond

We study the stability of systems of three giant planets orbiting 3-8 M☉ stars at orbital distances of >10 au as the host star ages through the main sequence (MS) and well into the white dwarf (WD) stage. Systems are stable on the MS if the planets are separated by more than ~9 Hill radii. Most systems surviving the MS will remain stable until the WD phase, although planets scattered on to small pericentres in unstable systems can be swallowed by the expanding stellar envelope when the star ascends the giant branches. Mass-loss at the end of the asymptotic giant branch triggers delayed instability in many systems, leading to instabilities typically occurring at WD cooling ages of a few 100 Myr. This instability occurs both in systems that survived the star's previous evolution unscathed, and in systems that previously underwent scattering instabilities. The outcome of such instability around WDs is overwhelmingly the ejection of one of the planets from the system, with several times more ejections occurring during the WD phase than during the MS. Furthermore, few planets are scattered close to the WD, just outside the Roche limit, where they can be tidally circularized. Hence, we predict that planets in WD systems rarely dynamically evolve to become `hot Jupiters'. Nor does it appear that the observed frequency of metal pollution in WD atmospheres can be entirely explained by planetesimals being destabilized following instability in systems of multiple giant planets, although further work incorporating low-mass planets and planetesimals is needed.
WEAK LENSING MEASUREMENT OF GALAXY CLUSTERS IN THE CFHTLS-WIDE SURVEY

We present the first weak gravitational lensing analysis of the completed Canada–France–Hawaii Telescope Legacy Survey (CFHTLS). We study the 64 deg2 W1 field, the largest of the CFHTLS-Wide survey fields, and present the largest contiguous weak lensing convergence “mass map” yet made. 2.66 million galaxy shapes are measured, using the Kaiser Squires and Broadhurst Method (KSB) pipeline verified against high-resolution Hubble Space Telescope imaging that covers part of the CFHTLS. Our i′-band measurements are also consistent with an analysis of independent r′-band imaging. The reconstructed lensing convergence map contains 301 peaks with signal-to-noise ratio ν > 3.5, consistent with predictions of a ΛCDM model. Of these peaks, 126 lie within 3. ′0 of a brightest central galaxy identified from multicolor optical imaging in an independent, red sequence survey. We also identify seven counterparts for massive clusters previously seen in X-ray emission within 6 deg2 XMM-LSS survey. With photometric redshift estimates for the source galaxies, we use a tomographic lensing method to fit the redshift and mass of each convergence peak. Matching these to the optical observations, we confirm 85 groups/clusters with χ2reduced < 3.0, at a mean redshift 〈zc〉 = 0.36 and velocity dispersion 〈σc〉 = 658.8 km s−1. Future surveys, such as DES, LSST, KDUST, and EUCLID, will be able to apply these techniques to map clusters in much larger volumes and thus tightly constrain cosmological models.
Utilization of elderly health promotion services during COVID 19 in Iran: A cross-sectional study

BACKGROUND: The outbreak of COVID-19 pandemic has made it difficult for older adults to utilize ordinary elder services. This cross-sectional study investigated the status of feeling the need, seek, and utilization of health promotion services among older adults in Ardabil, Iran, covered by the country's comprehensive health system during the pandemic. MATERIALS AND METHODS: This descriptive-analytical and cross-sectional study was conducted on 739 elderly people in Ardabil province. Cluster random sampling method was used for sampling. Data were gathered by referring trained individuals to the place of residence of the selected older adults Questionnaires were consisted of three parts: demographic information, household's economic status, and feeling the need, seek, and utilization from health promotion services. Multivariate logistic regression was used to separately model the need, seeking for, and utilization of health promotion services in STATA ver. 14. RESULTS: The mean age of the older adults in this study was 68.88 ± 4.72 years. The results indicate that men showed significantly greater need, seek for, and utilization of health promotion services during COVID- 19 than women. According to the results, people over the age of 80 had 4.08 times (95% confidence interval [CI]: 1.99–12.60) more need and utilization of health services than the older adults under 65 years. The results also indicate that use of health promotion services was significantly associated with being married (3.74, 95% CI: 1.22–2.62), having primary insurance and supplementary insurance (1.92, 95% CI: 1.21–3.12), and obesity (2.05, 95% CI: 1.13–3.76) in P < 0.05 level. Based on the results, people with chronic disease and obesity were more likely to utilize health promotion services. CONCLUSION: Findings suggest that the access and utilization of inpatient and outpatient health services by the elderly in the COVID-19 pandemic has somewhat decreased, which could be due to the fear of the disease being referred to health centers by the elderly. Hence, enabling conditions such as parental health care were major factors affecting health-seeking habits among the Iranian elder population.
Temporal signatures of leptohadronic feedback mechanisms in compact sources

The hadronic model of active galactic nuclei and other compact high-energy astrophysical sources assumes that ultra-relativistic protons, electron–positron pairs and photons interact via various hadronic and electromagnetic processes inside a magnetized volume, producing the multiwavelength spectra observed from these sources. A less studied property of such systems is that they can exhibit a variety of temporal behaviours due to the operation of different feedback mechanisms. We investigate the effects of one possible feedback loop, where γ-rays produced by photopion processes are being quenched whenever their compactness increases above a critical level. This causes a spontaneous creation of soft photons in the system that result in further proton cooling and more production of γ-rays, thus making the loop operate. We perform an analytical study of a simplified set of equations describing the system, in order to investigate the connection of its temporal behaviour with key physical parameters. We also perform numerical integration of the full set of kinetic equations verifying not only our analytical results but also those of previous numerical studies. We find that once the system becomes ‘supercritical’, it can exhibit either a periodic behaviour or a damped oscillatory one leading to a steady state. We briefly point out possible implications of such a supercriticality on the parameter values used in active galactic nuclei spectral modelling, through an indicative fitting of the VHE emission of blazar 3C 279.
Fermion structure of non-Abelian vortices in high density QCD

We study the internal structure of a non-Abelian vortex in color superconductivity with respect to quark degrees of freedom. Stable non-Abelian vortices appear in the color-flavor-locked phase whose symmetry SU(3){sub c+L+R} is further broken to SU(2){sub c+L+R} x U(1){sub c+L+R} at the vortex cores. Microscopic structure of vortices at scales shorter than the coherence length can be analyzed by the Bogoliubov-de Gennes equation (rather than the Ginzburg-Landau equation). We obtain quark spectra from the Bogoliubov-de Gennes equation by treating the diquark gap having the vortex configuration as a background field. We find that there are massless modes (zero modes) well-localized around a vortex, in the triplet and singlet states of the unbroken symmetry SU(2){sub c+L+R} x U(1){sub c+L+R}. The velocities v{sub i} of the massless modes (i=t, s for triplet and singlet) change at finite chemical potential {mu}{ne}0, and decrease as {mu} becomes large. Therefore, low energy excitations in the vicinity of the vortices are effectively described by 1+1 dimensional massless fermions whose velocities are reduced v{sub i}<1.
ON THE r-PROCESS ENRICHMENT OF DWARF SPHEROIDAL GALAXIES

Recent observations of Reticulum II have uncovered an overabundance of r-process elements compared to similar ultra-faint dwarf spheroidal galaxies (UFDs). Because the metallicity and star formation history of Reticulum II appear consistent with all known UFDs, the high r-process abundance of Reticulum II suggests enrichment through a single, rare event, such as a double neutron star (NS) merger. However, we note that this scenario is extremely unlikely, as binary stellar evolution models require significant supernova natal kicks to produce NS–NS or NS–black hole (BH) mergers, and these kicks would efficiently remove compact binary systems from the weak gravitational potentials of UFDs. We examine alternative mechanisms for the production of r-process elements in UFDs, including a novel mechanism wherein NSs in regions of high dark matter (DM) density implode after accumulating a BH-forming mass of DM. We find that r-process proto-material ejection by tidal forces, when a single NS implodes into a BH, can occur at a rate matching the r-process abundance of both Reticulum II and the Milky Way. Remarkably, DM models which collapse a single NS in observed UFDs also solve the missing pulsar problem in the Milky Way Galactic Center. We propose tests specific to DM r-process production which may uncover or rule out this model.
High-speed driving of a two-level system

A remarkably simple result is found for the optimal protocol of drivings for a general two-level Hamiltonian which transports a given initial state to a given final state in minimal time. If one of the three possible drivings is unconstrained in strength the problem is analytically completely solvable. A surprise arises for a class of states when one driving is bounded by a constant $c$ and the other drivings are constant. Then, for large $c$, the optimal driving is of type bang-off-bang and for increasing $c$ one recovers the unconstrained result. However, for smaller $c$ the optimal driving can suddenly switch to bang-bang type. It is also shown that for general states one may have a multistep protocol. The present paper explicitly proves and considerably extends the author's results contained in Phys. Rev. Lett. {\bf 111}, 260501 (2013).