cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Co2FeAl Heusler thin films grown on Si and MgO substrates: annealing temperature effect
Creators: name: Belmeguenai, M.
name: Tuzcuoglu, H.
name: Gabor, M. S.
name: Petrisor, T.
name: Tuisan, C.
name: Zighem, F.
name: Chérif, S. M.
name: Moch, P.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: 10 nm and 50 nm Co$_{2}$FeAl (CFA) thin films have been deposited on MgO(001) and Si(001) substrates by magnetron sputtering and annealed at different temperatures. X-rays diffraction revealed polycrystalline or epitaxial growth (according to the relation CFA(001)[110]//MgO(001)[100] epitaxial relation), respectively for CFA films grown on a Si and on a MgO substrate. For these later, the chemical order varies from the A2 phase to the B2 phase when increasing the annealing temperature (Ta) while only the A2 disorder type has been observed for CFA grown on Si. Microstrip ferromagnetic resonance (MS-FMR) measurements revealed that the in-plane anisotropy results from the superposition of a uniaxial and of a fourfold symmetry term for CFA grown on MgO substrates. This fourfold anisotropy, which disappears completely for samples grown on Si, is in accord with the crystal structure of the samples. The fourfold anisotropy field decreases when increasing Ta while the uniaxial anisotropy field is nearly unaffected by Ta within the investigated range. The MS-FMR data also allow for concluding that the gyromagnetic factor remains constant and that the exchange stiffness constant increases with $T_{a}$. Finally, the FMR linewidth decreases when increasing Ta, due to the enhancement of the chemical order. We derive a very low intrinsic damping parameter (1.3*10^-3 and 1.1*10^-3 for films of 50 nm thickness annealed at 615 °C grown on MgO and on Si, respectively).
description: 8 pages, 7 figures to appear in J. App. Phys
Solutions of complex differential equation having zeros on pre-given sequences
Creators: name: Gröhn, Janne
Publisher: name: arXiv
Year: 2017
Subjects: subject: Complex Variables (math.CV)
subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: Primary 34C10, Secondary 30D45

description: Behavior of solutions of $f''+Af=0$ is discussed under the assumption that $A$ is analytic in $\mathbb{D}$ and $\sup_{z\in\mathbb{D}}(1-|z|^2)^2|A(z)|<\infty$, where $\mathbb{D}$ is the unit disc of the complex plane. As a main result it is shown that such differential equation may admit a non-trivial solution whose zero-sequence does not satisfy the Blaschke condition. This gives an answer to an open question in the literature. It is also proved that $Λ\subset\mathbb{D}$ is the zero-sequence of a non-trivial solution of $f''+Af=0$ where $|A(z)|^2(1-|z|^2)^3\, dm(z)$ is a Carleson measure if and only if $Λ$ is uniformly separated. As an application an old result, according to which there exists a non-normal function which is uniformly locally univalent, is improved.
description: 11 pages
2010-Scott_Carrell-James_West-Does_Professor_Quality_Matter-Evidence_from_Random_Assignment_of_Students_to_Professors
Creators: name: Carrell, Scott
name: West, James
Publisher: name: QUBES Educational Resources
Year: 2023

description: In the postsecondary environment, scores on student evaluations of professors are typically used to measure teaching quality. We possess unique data that allow us to measure relative student performance in mandatory follow-on classes.
Slightly degenerate categories and $\mathbb{Z}$-modular data
Creators: name: Lacabanne, Abel
Publisher: name: arXiv
Year: 2018
Subjects: subject: Quantum Algebra (math.QA)
subject: Category Theory (math.CT)
subject: FOS: Mathematics

description: Given a slightly degenerate fusion category $\mathcal{C}$, we explain how it naturally gives rise to a Z-modular data. We do not restrict to spherical categories and work with pivotal categories instead. Finally, we give an interpretation in this framework of the Bonnafé-Rouquier categorification of the $\mathbb{Z}$-modular datum associated to non trivial family of the cyclic complex reflection group.
description: 24 pages, added some examples, a theorem of Vafa and removed a mild hypothesis in section 3
Fractional Fourier detection of Lévy Flights: application to Hamiltonian chaotic trajectories
Creators: name: Briolle, F.
name: Ricaud, B.
name: Leoncini, X.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: A signal processing method designed for the detection of linear (coherent) behaviors among random fluctuations is presented. It is dedicated to the study of data recorded from nonlinear physical systems. More precisely the method is suited for signals having chaotic variations and sporadically appearing regular linear patterns, possibly impaired by noise. We use time-frequency techniques and the Fractional Fourier transform in order to make it robust and easily implementable. The method is illustrated with an example of application: the analysis of chaotic trajectories of advected passive particles. The signal has a chaotic behavior and encounter Lévy flights (straight lines). The method is able to detect and quantify these ballistic transport regions, even in noisy situations.
Amorphous shear bands in crystalline materials as drivers of plasticity
Creators: name: Hu, Xuanxin
name: Liu, Nuohao
name: Jambur, Vrishank
name: Attarian, Siamak
name: Su, Ranran
name: Zhang, Hongliang
name: Xi, Jianqi
name: Luo, Hubin
name: Perepezko, John
name: Szlufarska, Izabela
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Traditionally, the formation of amorphous shear bands (SBs) in crystalline materials has been undesirable, because SBs can nucleate voids and act as precursors to fracture. They also form as a final stage of accumulated damage. Only recently SBs were found to form in undefected crystals, where they serve as the primary driver of plasticity without nucleating voids. Here, we have discovered trends in materials properties that determine when amorphous shear bands will form and whether they will drive plasticity or lead to fracture. We have identified the materials systems that exhibit SB deformation, and by varying the composition, we were able to switch from ductile to brittle behavior. Our findings are based on a combination of experimental characterization and atomistic simulations, and they provide a potential strategy for increasing toughness of nominally brittle materials.
Steady Twin-Jets Orientation: Implications For Their Formation Mechanism
Creators: name: Soker, Noam
name: Mcley, Liron
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We compare the structures of the jets of the pre-planetary nebulae (PN) CRL618 and the young stellar object (YSO) NGC 1333 IRAS4A2 and propose that in both cases the jets are launched near periastron passages of a highly eccentric binary system. The pre-PN CRL618 has two `twin-jets' on each side, where by `twin-jets' we refer to a structure where one side is composed of two very close and narrow jets that were launched at the same time. We analyze the position-velocity diagram of NGC 1333 IRAS4A2, and find that it also has the twin-jets structure. In both systems the orientation of the two twin-jets does not change with time. By comparing these two seemingly different objects, we speculate that the constant relative direction of the two twin-jets is fixed by the direction of a highly eccentric orbit of a binary star. For example, a double-arm spiral structure in the accretion disk induced by the companion might lead to the launching of the twin-jets. We predict the presence of a low-mass stelar companion in CRL618 that accretes mass and launches the jets, and a substellar (a planet of a brown dwarf) companion to the YSO NGC 1333 IRAS4A2 that perturbed the accretion disk. In both cases the orbit has a high eccentricity.
description: Submitted to ApJ Letters. arXiv admin note: substantial text overlap with arXiv:1209.0986
Drinfeld double of quantum groups, tilting modules and $\mathbb{Z}$-modular data associated to complex reflection groups
Creators: name: Lacabanne, Abel
Publisher: name: arXiv
Year: 2018
Subjects: subject: Quantum Algebra (math.QA)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: Generalizing Lusztig's work, Malle has associated to some imprimitive complex reflection group $W$ a set of "unipotent characters", which are in bijection of the usual unipotent characters of the associated finite reductive group if $W$ is a Weyl group. He also obtained a partition of these characters into families and associated to each family a $\mathbb{Z}$-modular datum. We construct a categorification of some of these data, by studying the category of tilting modules of the Drinfeld double of the quantum enveloping algebra of the Borel of a simple complex Lie algebra.
description: 42 pages, some comments added on a conjecture of Cuntz
Success factors to establish an International Branch Campus: An Australian/ Indonesian case study
Creators: name: Stevens-Guiney, Priscilla
Publisher: name: CQUniversity
Year: 2023
Subjects: classificationCode: 399999
subject: Other education not elsewhere classified

description: This qualitative study examined success factors for establishing an International Branch Campus (IBC) based on CQUniversity’s experience in Indonesia. It applied Actor Network Theory to understand the impact of human relationships on IBC success, and developed a new conceptual framework to support IBC establishment for higher education institutions.
Crossed $S$-matrices and Fourier matrices for Coxeter groups with automorphism
Creators: name: Lacabanne, Abel
Publisher: name: arXiv
Year: 2019
Subjects: subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics

description: We study crossed $S$-matrices for braided $G$-crossed categories and reduce their computation to a submatrix of the de-equivariantization. We study the more general case of a category containing the symmetric category $\mathrm{Rep}(A,z)$ with $A$ a finite cyclic group and $z\in A$ such that $z^2=1$. We give two example of such categories, which enable us to recover the Fourier matrix associated with the big family of unipotent characters of the dihedral groups with automorphism as well as the Fourier matrix of the big family of unipotent characters of the Ree group of type ${}^2F_4$.
description: 25 pages, comments welcome
Polyhedral Covers of Tree Space
Creators: name: Devadoss, Satyan L.
name: Huang, Daoji
name: Spadacene, Dominic
Publisher: name: arXiv
Year: 2013
Subjects: subject: Combinatorics (math.CO)
subject: Discrete Mathematics (cs.DM)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: The phylogenetic tree space, introduced by Billera, Holmes, and Vogtmann, is a cone over a simplicial complex. In this short article, we construct this complex from local gluings of classical polytopes, the associahedron and the permutohedron. Its homotopy is also reinterpreted and calculated based on polytope data.
description: 8 pages, 9 figures
The Statistical Properties of Superfluid Turbulence in $^4$He from the Hall-Vinen-Bekharevich-Khalatnikov Model
Creators: name: Verma, Akhilesh Kumar
name: Shukla, Sanjay
name: Shukla, Vishwanath
name: Basu, Abhik
name: Pandit, Rahul
Publisher: name: arXiv
Year: 2019
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We obtain the von Kármán-Howarth relation for the stochastically forced three-dimensional Hall-Vinen-Bekharvich-Khalatnikov (3D HVBK) model of superfluid turbulence in Helium ($^4$He) by using the generating-functional approach. We combine direct numerical simulations (DNSs) and analyitcal studies to show that, in the statistically steady state of homogeneous and isotropic superfluid turbulence, in the 3D HVBK model, the probability distribution function (PDF) $P(γ)$, of the ratio $γ$ of the magnitude of the normal fluid velocity and superfluid velocity, has power-law tails that scale as $P(γ) \sim γ^3$, for $γ\ll 1$, and $P(γ) \sim γ^{-3}$, for $γ\gg 1$. Furthermore, we show that the PDF $P(θ)$, of the angle $θ$ between the normal-fluid velocity and superfluid velocity exhibits the following power-law behaviors: $P(θ)\sim θ$ for $θ\ll θ_*$ and $P(θ)\sim θ^{-4}$ for $θ_* \ll θ\ll 1$, where $θ_*$ is a crossover angle that we estimate. From our DNSs we obtain energy, energy-flux, and mutual-friction-transfer spectra, and the longitudinal-structure-function exponents for the normal fluid and the superfluid, as a function of the temperature $T$, by using the experimentally determined mutual-friction coefficients for superfluid Helium $^4$He, so our results are of direct relevance to superfluid turbulence in this system.
description: 13 pages, 3 figures
Strong gravitational lensing by wormholes
Creators: name: Shaikh, Rajibul
name: Banerjee, Pritam
name: Paul, Suvankar
name: Sarkar, Tapobrata
Publisher: name: arXiv
Year: 2019
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study strong gravitational lensing by a class of static wormhole geometries. Analytical approaches to the same are developed, and the results differ substantially from strong lensing by black holes, first reported by Bozza. We consider two distinct situations, one in which the observer and the source are on the same side of the wormhole throat, and the other in which they are on opposite sides. Distinctive features in our study arise from the fact that photon and antiphoton spheres might be present on both sides of the wormhole throat, and that the throat might itself act as a photon sphere. We show that strong gravitational lensing thus opens up a rich variety of possibilities of relativistic image formation, some of which are novel, and are qualitatively distinct from black hole lensing. These can serve as clear indicators of exotic wormhole geometries.
description: 29 pages, 7 figures, published in JCAP, references added
Short-axis-mode rotation of a free rigid body by perturbation series
Creators: name: Lara, Martin
Publisher: name: arXiv
Year: 2013
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics

description: A simple rearrangement of the torque free motion Hamiltonian shapes it as a perturbation problem for bodies rotating close to the principal axis of maximum inertia, independently of their triaxiality. The complete reduction of the main part of this Hamiltonian via the Hamilton-Jacobi equation provides the action-angle variables that ease the construction of a perturbation solution by Lie transforms. The lowest orders of the transformation equations of the perturbation solution are checked to agree with Kinoshita's corresponding expansions for the exact solution of the free rigid body problem. For approximately axisymmetric bodies rotating close to the principal axis of maximum inertia, the common case of major solar system bodies, the new approach is advantageous over classical expansions based on a small triaxiality parameter.
description: 22 pages, 1 figure, to be presented in 2013 AAS/AIAA Astrodynamics Specialist Conference, Hilton Head, South Carolina, August 11 - 15, 2013
Three dimensional compressible Navier-Stokes equation - self-similar and traveling wave solutions
Creators: name: Barna, I. F.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We investigate the three dimensional compressible Navier-Stokes and the continuity equations in Cartesian coordinates for Newtonian fluids. The polytropic equation of sate is used as closing condition. The key idea is the three-dimensional generalization of the well-known self-similar Ansatz which was already used for non-compressible viscous flow in our former study (Commun. in Theor. Phys. 56, (2011) 745). In the second method the three dimensional traveling wave Ansatz was applied. The geometrical interpretations of the trial functions are also discussed.
description: 15 pages 4 figures, submitted to Commun. in Theor. Phys. arXiv admin note: text overlap with arXiv:1102.5504
The $^3$He$(e,e^\prime p)^2$H and $^4$He$(e,e^\prime p)^3$H reactions at high momentum transfer
Creators: name: Ford, W. P.
name: Schiavilla, R.
name: Van Orden, J. W.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present updated calculations for observables in the processes $^3$He($e,e^\prime p$)$^2$H, $^4$He($e,e^\prime p$)$^3$H, and $^4$He($\vec{e},e^\prime \vec{p}\,$)$^3$H. This update entails the implementation of improved nucleon-nucleon ($NN$) amplitudes to describe final state interactions (FSI) within a Glauber approximation and includes full spin-isospin dependence in the profile operator. In addition, an optical potential, which has also been updated since previous work, is utilized to treat FSI for the $^4$He($e,e^\prime p$)$^3$H and $^4$He($\vec{e},e^\prime \vec{p}\,$)$^3$H reactions. The calculations are compared with experimental data and show good agreement between theory and experiment. Comparisons are made between the various approximations in the Glauber treatment, including model dependence due to the $NN$ scattering amplitudes, rescattering contributions, and spin dependence. We also analyze the validity of the Glauber approximation at the kinematics the data is available, by comparing to the results obtained with the optical potential.
Description of growth and oscillation of solutions of complex LDE's
Creators: name: Chyzhykov, Igor
name: Gröhn, Janne
name: Heittokangas, Janne
name: Rättyä, Jouni
Publisher: name: arXiv
Year: 2019
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics

description: It is known that, equally well in the unit disc as in the whole complex plane, the growth of the analytic coefficients $A_0,\dotsc,A_{k-2}$ of \begin{equation*} f^{(k)} + A_{k-2} f^{(k-2)} + \dotsb + A_1 f'+ A_0 f = 0, \quad k\geq 2, \end{equation*} determines, under certain growth restrictions, not only the growth but also the oscillation of its non-trivial solutions, and vice versa. A uniform treatment of this principle is given in the disc $D(0,R)$, $0
description: 24 pages. This is a revision of a previously announced preprint. There are many changes throughout the manuscript
Thin accretion disk images of the black hole in symmergent gravity
Creators: name: Çimdiker, İlim İrfan
name: Övgün, Ali
name: Demir, Durmuş
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper, we study circular orbits, effective potential, and thin-accretion disk of a black hole in symmergent gravity within the Novikov-Thorne model in a way including the energy flux and temperature distribution. We determine bounds on symmergent gravity parameters and conclude that the accretion disk could be used as an astrophysical tool to probe symmergent gravity.
description: 30 pages. Accepted for publication in Classical and Quantum Gravity, "Special Issue: Focus on Quantum Gravity Phenomenology in the Multi-Messenger Era: Challenges and Perspectives" (https://iopscience.iop.org/article/10.1088/1361-6382/aceb45). arXiv admin note: text overlap with arXiv:1901.05762, arXiv:2002.00589 by other authors
A Simple Proof of the Riemann's Hypothesis
Creators: name: Ech-Chatbi, Charaf
Publisher: name: arXiv
Year: 2019
Subjects: subject: General Mathematics (math.GM)
subject: FOS: Mathematics
subject: 11, 26, 30, 40

description: We present a simple proof of the Riemann's Hypothesis (RH) where only undergraduate mathematics is needed.
description: 7 pages Only. Only undergraduate mathematics is used
Recent progress in perpendicularly magnetized Mn-based binary alloy films
Creators: name: Zhu, Lijun
name: Nie, Shuaihua
name: Zhao, Jianhua
Publisher: name: arXiv
Year: 2013
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In this article, we review the recent progress in growth, structural characterization, magnetic properties and related spintronic devices of tetragonal MnxGa and MnxAl thin films with perpendicular magnetic anisotropy. In the first part of this review, we present a brief introduction to the demands for perpendicularly magnetized materials in spintronics, magnetic recording and permanent magnets applications, and the most promising candidates of tetragonal MnxGa and MnxAl with strong perpendicular anisotropy. Then, in the second and third parts, we focus on the recent progress of perpendicularly magnetized MnxGa and MnxAl, respectively, including their lattice structures, bulk synthesis, epitaxial growth, structural chracterizations, magnetic and other spin-dependent properties, and spintronic devices like magnetic tunneling junctions, spin valves and spin injector into semiconductors. Finally, we give a summary and a perspective of these perpendicularly magnetized Mn-based binary alloy films for future applications.
description: Chinese Physics B 2013
Emergence of massless Dirac fermions in graphene's Hofstadter butterfly at switches of the quantum Hall phase connectivity
Creators: name: Diez, M.
name: Dahlhaus, J. P.
name: Wimmer, M.
name: Beenakker, C. W. J.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The fractal spectrum of magnetic minibands (Hofstadter butterfly), induced by the moiré super- lattice of graphene on an hexagonal crystal substrate, is known to exhibit gapped Dirac cones. We show that the gap can be closed by slightly misaligning the substrate, producing a hierarchy of conical singularities (Dirac points) in the band structure at rational values Phi = (p/q)(h/e) of the magnetic flux per supercell. Each Dirac point signals a switch of the topological quantum number in the connected component of the quantum Hall phase diagram. Model calculations reveal the scale invariant conductivity sigma = 2qe^2 / pi h and Klein tunneling associated with massless Dirac fermions at these connectivity switches.
description: 4 pages, 6 figures + appendix (3 pages, 1 figure)
On a conjecture about cellular characters for the complex reflection group $G(d,1,n)$
Creators: name: Lacabanne, Abel
Publisher: name: arXiv
Year: 2019
Subjects: subject: Representation Theory (math.RT)
subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics

description: We propose a conjecture relating two different sets of characters for the complex reflection group $G(d,1,n)$. From one side, the characters are afforded by Calogero-Moser cells, a conjectural generalisation of Kazhdan-Lusztig cells for a complex reflection group. From the other side, the characters arise from a level $d$ irreducible integrable representations of $\mathcal{U}_q(\mathfrak{sl}_{\infty})$. We prove this conjecture in some cases: in full generality for $G(d,1,2)$ and for generic parameters for $G(d,1,n)$.
description: 24 pages, comments welcome v2: minor corrections
Precision measurement of $^{65}$Zn electron-capture decays with the KDK coincidence setup
Creators: name: Hariasz, L.
name: Di Stefano, P. C. F.
name: Stukel, M.
name: Rasco, B. C.
name: Rykaczewski, K. P.
name: Brewer, N. T.
name: Grzywacz, R. K.
name: Lukosi, E. D.
name: Stracener, D. W.
name: Mancuso, M.
name: Petricca, F.
name: Ninkovic, J.
name: Lechner, P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: $^{65}$Zn is a common calibration source, moreover used as a radioactive tracer in medical and biological studies. In many cases, $γ$-spectroscopy is a preferred method of $^{65}$Zn standardization, which relies directly on the branching ratio of $J π(^{65}\text{Zn} ) = 5/2^- \rightarrow J π(^{65}\text{Cu}) = 5/2^- $ via electron capture (EC*). We measure the relative intensity of this branch to that proceeding directly to the ground state (EC$^0$) using a novel coincidence technique, finding $I_{\text{EC}^0}/I_{\text{EC*}} = 0.9684 \pm 0.0018$. Re-evaluating the decay scheme of $^{65}$Zn by adopting the commonly evaluated branching ratio of $I_{β^+}= 1.4271(7)\%$ we obtain $I_{\text{EC*}} = (50.08 \pm 0.06)\%$, and $I_\text{EC^0} = (48.50 \pm 0.06) \%$. The associated 1115 keV gamma intensity agrees with the previously reported NNDC value, and is now accessible with a factor of ~2 increase in precision. Our re-evaluation removes reliance on the deduction of this gamma intensity from numerous measurements, some of which disagree and depend directly on total activity determination. The KDK experimental technique provides a new avenue for verification or updates to the decay scheme of $^{65}$Zn, and is applicable to other isotopes.
description: Uses similar methodology to the 40K measurement by the KDK Collaboration (Stukel et al PRL 2023, arXiv:2211.10319; Hariasz et al PRC 2023, arXiv:2211.10343), as such there may be some similarity in figures and text
Heavy Traffic Scaling Limits for shortest remaining processing time queues with heavy tailed processing time distributions
Creators: name: Banerjee, Sayan
name: Budhiraja, Amarjit
name: Puha, Amber L.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: Primary 60K25, 60F17, Secondary 60G57, 60G60, 68M20

description: We study a single server queue operating under the shortest remaining processing time (SRPT) scheduling policy; that is, the server preemptively serves the job with the shortest remaining processing time first. In this work we are interested in studying the asymptotic behavior of suitably scaled measure-valued state descriptors that describe the evolution of a sequence of SRPT queuing systems. Gromoll, Kruk, and Puha (2011) have studied this problem under diffusive scaling. In the setting where the processing time distributions have unbounded support, under suitable conditions, they show that the diffusion scaled measures converge in distribution to the process that is identically zero. In Puha (2015) for the setting where the processing time distributions have unbounded support and light tails, a non-standard scaling of the queue length process is shown to give rise to a form of state space collapse that results in a nonzero limit. In the current work we consider the case where processing time distributions have finite second moments and regularly varying tails. We show that the measure valued process, under a non-standard scaling, converges in distribution in the space of paths of measures. In sharp contrast with previous results, there is no state space collapse. Nevertheless, the description of the limit is simple and given explicitly in terms of a certain $\mathbb{R}_+$ valued random field which is determined from a single Brownian motion. Along the way we establish convergence of suitably scaled workload and queue length processes. We also show that as the tail of the distribution of job processing times becomes lighter in an appropriate fashion, the difference between the limiting queue length process and the limiting workload process converges to zero, thereby approaching the behavior of state space collapse.
description: 64 pages, to appear in The Annals of Applied Probability
Dark Energy is the Cosmological Quantum Vacuum Energy of Light Particles-The Axion and the Lightest Neutrino
Creators: name: de Vega, Hector J.
name: Sanchez, Norma G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We uncover the general mechanism producing the dark energy(DE). This is only based on well known quantum physics and cosmology. We show that the observed DE originates from the cosmological quantum vacuum of light particles which provides a continuous energy distribution able to reproduce the data. Bosons give positive contributions to the DE while fermions yield negative contributions. As usual in field theory, ultraviolet divergences are subtracted from the physical quantities. The subtractions respect the symmetries of the theory and we normalize the physical quantities to be zero for the Minkowski vacuum. The resulting finite contributions to the energy density and the pressure from the quantum vacuum grow as log a(t) where a(t) is the scale factor, while the particle contributions dilute as 1/a^3(t), as it must be for massive particles. The DE equation of state P = w(z)H turns to be w(z)<-1 with w(z) asymptotically reaching the value -1 from below.A scalar particle can produce the observed DE through its quantum cosmological vacuum provided:(i)its mass is of the order of 10^{-3} eV = 1 meV,(ii) it is very weakly coupled and (iii) it is stable on the time scale of the age of the universe. The axion vacuum thus appears as a natural candidate. The neutrino vacuum (especially the lightest mass eigenstate) can give negative contributions to the DE. We find that w(z=0) is slightly below -1 by an amount ranging from [-1.5 10^{-3}] to [-8 10^{-3}] and we predict the axion mass to be in the range between 4 and 5 meV. We find that the universe will expand in the future faster than the de Sitter universe, as an exponential in the square of the cosmic time. DE arises from the quantum vacua of light particles in FRW cosmological space time in an analogous way to the Casimir effect in Minkowski spacetime with non trivial boundaries.
description: Original new material,42 pages, 1 figure, 1 table. Expanded and updated published version in Universe 31 march 2023. This article belongs to the Special Issue Quantum Physics including Gravity: Highlights and Novelties https://www.mdpi.com/journal/universe/special_issues/44645D0TKA
Discovery of weak 6.7-GHz CH3OH masers in a sample of high-mass Hi-GAL sources
Creators: name: Olmi, L.
name: Araya, E. D.
name: Hofner, P.
name: Molinari, S.
name: Ortiz, J. Morales
name: Moscadelli, L.
name: Pestalozzi, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Maser lines from different molecular species, including water, hydroxyl, and methanol, are common observational phenomena associated with massive star forming regions. In particular, the methanol maser appears as an ideal tool to study the early phases of massive star formation. However, it is difficult to establish the exact start of the methanol maser phase, and it would then be interesting to detect and study low-flux density methanol masers (i.e., < 0.1 Jy or even << 0.1 Jy), in order to determine if they can effectively be used to mark a specific evolutionary phase in high-mass star formation. Past surveys have been unable to systematically detect many low-flux density methanol masers, and thus we do not yet know how many such masers exist in the Galaxy and what is their physical nature. Out of a sample of 107 observed Hi-GAL sources we detected a total of 32 methanol masers, with 22 sources being new and weak (median peak flux density 0.07 Jy) detections, in the Galactic longitude range [32.0, 59.8]deg. We also detected 12 6.035-GHz OH maser, with 9 objects being new detections. Our survey covers a similar range of source distances as the "Arecibo Methanol Maser Galactic Plane Survey", but the methanol masers detected by us are clearly shifted towards lower integrated flux densities. The newly detected methanol masers are mostly of low-luminosity and, except for some sources, their weakness is not due to distance effects or positional offsets. No specific correlation is found with the physical parameters of the Hi-GAL clumps, except for sources with both CH3OH and OH masers which tend to have higher mass and luminosity. The intensity of the methanol masers correlates well with the velocity range of the maser emission, which suggests that the low brightness of these masers is related to the number of maser spots in the emitting region and their evolution with time.
description: This paper contains a total of 14 figures and 7 tables. Submitted for publication to A&A on November 4th, 2013
Core-collapse Supernovae and Gamma-ray Bursts in TMT Era
Creators: name: Pandey, S. B.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Study of energetic cosmic explosions as a part of time domain astronomy is one of the key areas that could be pursued with upcoming Giant segmented optical-IR telescopes with a very large photon collecting area applying cutting edge technology. Existing 8-10m class telescopes have been helpful to improve our knowledge about Core-Collapse Supernovae, Gamma-ray Bursts and nature of their progenitors and explosion mechanisms. However, many aspects about these energetic cosmic explosions are still not well-understood and require much bigger telescopes and back-end instruments with high precision to address the evolution of massive stars and high-redshift Universe in more detail. In this presentation, possible thrust research areas towards Core-Collapse Supernovae and Gamma-ray Bursts with the Thirty Meter Telescope and back-end instruments are presented.
description: 19 pages, 3 figures, accepted for publication in Journal of Astronomy and Astrophysics, an article based on a presentation during "TMT Science and Instrumentation workshop, 10-12 December 2012, IUCAA Pune, India"
The Relativistic Rotation
Creators: name: Cao, Z. X.
name: Chen, Ch. L.
name: Liu, L.
Publisher: name: arXiv
Year: 2003
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: The classical rotation is not self-consistent in the framework of the special theory of relativity. the Relativistic rotation is obtained, which takes the relativistic effect into account. It is demonstrated that the angular frequency of classical rotation is only valid in local approximation. The properties of the relativistic rotation and the relativistic transverse Doppler shift are discussed in this work.
The Asymptotic Statistics of Random Covering Surfaces
Creators: name: Magee, Michael
name: Puder, Doron
Publisher: name: arXiv
Year: 2020
Subjects: subject: Group Theory (math.GR)
subject: Geometric Topology (math.GT)
subject: Probability (math.PR)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 20B30, 20P05, 20C30, 20F34, 20F65, 20F70

description: Let $Γ_{g}$ be the fundamental group of a closed connected orientable surface of genus $g\geq2$. We develop a new method for integrating over the representation space $\mathbb{X}_{g,n}=\mathrm{Hom}(Γ_{g},S_{n})$ where $S_{n}$ is the symmetric group of permutations of $\{1,\ldots,n\}$. Equivalently, this is the space of all vertex-labeled, $n$-sheeted covering spaces of the the closed surface of genus $g$. Given $ϕ\in\mathbb{X}_{g,n}$ and $γ\inΓ_{g}$, we let $\mathsf{fix}_γ(ϕ)$ be the number of fixed points of the permutation $ϕ(γ)$. The function $\mathsf{fix}_γ$ is a special case of a natural family of functions on $\mathbb{X}_{g,n}$ called Wilson loops. Our new methodology leads to an asymptotic formula, as $n\to\infty$, for the expectation of $\mathsf{fix}_γ$ with respect to the uniform probability measure on $\mathbb{X}_{g,n}$, which is denoted by $\mathbb{E}_{g,n}[\mathsf{fix}_γ]$. We prove that if $γ\inΓ_{g}$ is not the identity, and $q$ is maximal such that $γ$ is a $q$th power in $Γ_{g}$, then \[ \mathbb{E}_{g,n}[\mathsf{fix}_γ]=d(q)+O(n^{-1}) \] as $n\to\infty$, where $d\left(q\right)$ is the number of divisors of $q$. Even the weaker corollary that $\mathbb{E}_{g,n}[\mathsf{fix}_γ]=o(n)$ as $n\to\infty$ is a new result of this paper. We also prove that if $γ$ is not the identity then $\mathbb{E}_{g,n}[\mathsf{fix}_γ]$ can be approximated to any order $O(n^{-M})$ by a polynomial in $n^{-1}$.
description: 51 pages, 6 figures. Slightly simplified Sections 5.2 and 5.4
title: The Brussels Effect in Action: Do the EU’s Standards Travel Abroad? : A Study on Control Systems for Geographical Indications in the EU and Thailand
Creators: name: Preusse, Verena
name: Purnhagen, Kai
name: Dries, Lisbeth
Publisher: name: University of Bayreuth
Year: 2020
Subjects: subject: Brussels Effect
subject: Geographical Indications
subject: Thailand
subject: Comparative Law
subject: Germany
subject: European Union
subject: 340

description: This article examines to what extent EU law influences standards for geographical indications (GI) control beyond the EU’s regulatory borders. In light of the concept of the “Brussels Effect” and taking a socio-legal comparative methodological approach, it analyzes and compares how the EU and Thailand regulate and implement GI controls in practice. The analysis of the practical implementation of GI controls is based on one case study from the EU (Germany) and two case studies from Thailand. Ultimately, this article discusses to what extent EU GI regulations shape the regulation and practical implementation of GI controls in Thailand. The findings indicate that Thai producers whose products are registered as GIs in the EU adopt the EU’s more stringent standards for control, while fundamental differences between the EU and Thailand prevail on the regulatory level.
Fermi Surface of KFe$_2$As$_2$ from Quantum Oscillations in Magnetostriction
Creators: name: Zocco, D. A.
name: Grube, K.
name: Eilers, F.
name: Wolf, T.
name: Löhneysen, H. v.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We present a study of the Fermi surface of KFe$_2$As$_2$ single crystals. Quantum oscillations were observed in magnetostriction measured down to 50 mK and in magnetic fields $H$ up to 14 T. For $H \parallel c$, the calculated effective masses are in agreement with recent de Haas-van Alphen and ARPES experiments, showing enhanced values with respect to the ones obtained from previous band calculations. For $H \parallel a$, we observed a small orbit at a cyclotron frequency of 64 T, characterized by an effective mass of $\sim 0.8 m_e$, supporting the presence of a three-dimensional pocket at the Z-point.
description: SCES Conference, Tokyo 2013
Quantitative lower bounds to the Euclidean and the Gaussian Cheeger constants
Creators: name: Julin, Vesa
name: Saracco, Giorgio
Publisher: name: arXiv
Year: 2020
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 49Q10, 49Q20, 39B62

description: We provide a quantitative lower bound to the Cheeger constant of a set $Ω$ in both the Euclidean and the Gaussian settings in terms of suitable asymmetry indexes. We provide examples which show that these quantitative estimates are sharp.
description: 18 pages, 3 figures. In the published paper in the definition (2.2) of the index $\zeta(\Omega)$ the rescaling factor is missing (as otherwise the quantitative inequality (2.5) would be false as written). Consequently, in the proof of Theorem 2.1 and in the following example several renormalization constants are missing. The preprint contains the correct definition and proofs
Dynamical low-noise microwave source for cold-atom experiments
Creators: name: Meyer-Hoppe, Bernd
name: Baron, Maximilian
name: Cassens, Christophe
name: Anders, Fabian
name: Idel, Alexander
name: Peise, Jan
name: Klempt, Carsten
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: The generation and manipulation of ultracold atomic ensembles in the quantum regime require the application of dynamically controllable microwave fields with ultra-low noise performance. Here, we present a low-phase-noise microwave source with two independently controllable output paths. Both paths generate frequencies in the range of $6.835\,$GHz $\pm$ $25\,$MHz for hyperfine transitions in $^{87}$Rb. The presented microwave source combines two commercially available frequency synthesizers: an ultra-low-noise oscillator at $7\,$GHz and a direct digital synthesizer for radiofrequencies. We demonstrate a low integrated phase noise of $480\,μ$rad in the range of $10\,$Hz to $100\,$kHz and fast updates of frequency, amplitude and phase in sub-$μ$s time scales. The highly dynamic control enables the generation of shaped pulse forms and the deployment of composite pulses to suppress the influence of various noise sources.
description: 7 pages, 8 figures
Variability of paths and differential equations with $BV$-coefficients
Creators: name: Hinz, Michael
name: Tölle, Jonas M.
name: Viitasaari, Lauri
Publisher: name: arXiv
Year: 2020
Subjects: subject: Probability (math.PR)
subject: Analysis of PDEs (math.AP)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 31B10, 34A12, 34A34 (primary), 26A33, 26A42, 26B30, 26B35, 28A78, 31B99, 60G22 (secondary)

description: We define compositions $φ(X)$ of Hölder paths $X$ in $\mathbb{R}^n$ and functions of bounded variation $φ$ under a relative condition involving the path and the gradient measure of $φ$. We show the existence and properties of generalized Lebesgue-Stieltjes integrals of compositions $φ(X)$ with respect to a given Hölder path $Y$. These results are then used, together with Doss' transform, to obtain existence and, in a certain sense, uniqueness results for differential equations in $\mathbb{R}^n$ driven by Hölder paths and involving coefficients of bounded variation. Examples include equations with discontinuous coefficients driven by paths of two-dimensional fractional Brownian motions.
description: 67 pages, 102 references
Towards ultra-sensitive SQUIDs based on sub-micrometer-sized Josephson Junctions
Creators: name: Storm, Jan-Hendrik
name: Kieler, Oliver
name: Körber, Rainer
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We recently demonstrated a 1$^{\textrm{st}}$-order axial gradiometer SQUID system, which is operated in a liquid He dewar with negligible noise contribution. The achieved close to SQUID-limited measured coupled energy sensitivity $\varepsilon_{c}$ of $\sim 30\,h$ corresponds to a white field noise below 180~aT~Hz${^{-1/2}}$. In order to further improve the SQUID noise performance, the junction capacitance was reduced by decreasing its lateral size from $2.5~μ$m to below $1~μ$m. This was realized by extending the fabrication process for submicrometer-sized Josephson Junctions based on the HfTi self-shunted junction technology to an SIS process with AlO$_{\textrm{x}}$ as the insulating layer. We achieved energy sensitivities of 4.7$\,h$ and 20$\,h$ at 4.2~K for uncoupled and coupled SQUIDs, respectively. We also investigated the temperature dependence of the noise of the uncoupled SQUIDs and reached an energy sensitivity of 0.65$\,h$ in the white noise regime at 400~mK.
description: 4 pages, 7 figures, ISEC 2019, version containing all the proofs (provided to IEEE TAS prior to publication) which should have been published by IEEE TAS
title: EU Regulation of New Plant Breeding Technologies and their Possible Economic Implications for the EU and Beyond
Creators: name: Wesseler, Justus H. H.
name: Purnhagen, Kai
Publisher: name: University of Bayreuth
Year: 2020
Subjects: subject: Gene Editing
subject: Investment
subject: Plant Breeding
subject: Real Options
subject: Regulation
subject: European Union
subject: 340

description: New plant breeding technologies (NPBTs), including CRISPR gene editing, are being used widely, and they are driving the development of new crops. They are nevertheless a subject of criticism and discussion. According to a summer 2018 interpretation by the Court of Justice of the European Union (CJEU), European Union (EU) law makes most NPBTS subject to regulations governing the use of genetically modified organisms (GMOs) in the EU. The implications of this decision have been widely discussed in the literature, thereby stressing the importance of the decision for plant breeding and international trade within and beyond the EU. This contribution summarizes the status of the debate and highlights issues that have thus far not been considered—particularly with regard to the implications of EU regulations for NPBTs for countries outside the EU. We conclude that the practical implications of the CJEU decision reduce the EU’s comparative advantage and increase the cost of achieving the objectives of the European Green Deal. Our findings reveal an almost complete lack of possibilities for changing the current situation. China and countries oriented towards China are the most likely economic beneficiaries of the current situation.
Conformal scattering theories for tensorial wave equations on Schwarzschild spacetime
Creators: name: Xuan, Pham Truong
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: Analysis of PDEs (math.AP)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In this paper, we establish the constructions of conformal scattering theories for the tensorial wave equation such as the tensorial Fackerell-Ipser and the spin $\pm 1$ Teukolsky equations on Schwarzschild spacetime. In our strategy, we construct the conformal scattering for the tensorial Fackerell-Ipser equations which are obtained from the Maxwell equation and spin $\pm 1$ Teukolsky equations. Our method combines Penrose's conformal compactification and the energy decay results of the tensorial fields satisfying the tensorial Fackerell-Ipser equation to prove the energy equality of the fields through the conformal boundary $\mathfrak{H}^+\cup \scri^+$ (resp. $\mathfrak{H}^-\cup \scri^-$) and the initial Cauchy hypersurface $Σ_0 = \left\{ t=0 \right\}$. We will prove the well-posedness of the Goursat problem by using a generalization of Hörmander's results for the tensorial wave equations. By using the results for the tensorial Fackerell-Ipser equations we will establish the construction of conformal scattering for the spin $\pm 1$ Teukolsky equations.
description: 48 pages, 5 figures
WD3: Taming the Estimation Bias in Deep Reinforcement Learning
Creators: name: He, Qiang
name: Hou, Xinwen
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: The overestimation phenomenon caused by function approximation is a well-known issue in value-based reinforcement learning algorithms such as deep Q-networks and DDPG, which could lead to suboptimal policies. To address this issue, TD3 takes the minimum value between a pair of critics. In this paper, we show that the TD3 algorithm introduces underestimation bias in mild assumptions. To obtain a more precise estimation for value function, we unify these two opposites and propose a novel algorithm \underline{W}eighted \underline{D}elayed \underline{D}eep \underline{D}eterministic Policy Gradient (WD3), which can eliminate the estimation bias and further improve the performance by weighting a pair of critics. To demonstrate the effectiveness of WD3, we compare the learning process of value function between DDPG, TD3, and WD3. The results verify that our algorithm does eliminate the estimation error of value functions. Furthermore, we evaluate our algorithm on the continuous control tasks. We observe that in each test task, the performance of WD3 consistently outperforms, or at the very least matches, that of the state-of-the-art algorithms\footnote{Our code is available at~\href{https://sites.google.com/view/ictai20-wd3/}{https://sites.google.com/view/ictai20-wd3/}.}.
description: Accepted to ICTAI'20. Code: https://sites.google.com/view/ictai20-wd3/