cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Mock Modular Mathieu Moonshine Modules
Creators: name: Cheng, Miranda C. N.
name: Dong, Xi
name: Duncan, John F. R.
name: Harrison, Sarah
name: Kachru, Shamit
name: Wrase, Timm
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Representation Theory (math.RT)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We construct super vertex operator algebras which lead to modules for moonshine relations connecting the four smaller sporadic simple Mathieu groups with distinguished mock modular forms. Starting with an orbifold of a free fermion theory, any subgroup of Co_0 that fixes a 3-dimensional subspace of its unique non-trivial 24-dimensional representation commutes with a certain N=4 superconformal algebra. Similarly, any subgroup of Co_0 that fixes a 2-dimensional subspace of the 24-dimensional representation commutes with a certain N=2 superconformal algebra. Through the decomposition of the corresponding twined partition functions into characters of the N=4 (resp. N=2) superconformal algebra, we arrive at mock modular forms which coincide with the graded characters of an infinite-dimensional Z-graded module for the corresponding group. The Mathieu groups are singled out amongst various other possibilities by the moonshine property: requiring the corresponding weak Jacobi forms to have certain asymptotic behaviour near cusps. Our constructions constitute the first examples of explicitly realized modules underlying moonshine phenomena relating mock modular forms to sporadic simple groups. Modules for other groups, including the sporadic groups of McLaughlin and Higman--Sims, are also discussed.
description: 94 pages, including 56 pages of tables; v2: updated references and minor revisions to abstract, introduction and sections 8 and 9
APPLICATION OF L-METHIONINE CONFERS SALINITY TOLERANCE IN MAIZE THROUGH MODULATION OF METABOLITES AND ANTIOXIDATIVE DEFENSE
Creators: name: REEMA ARSHAD
name: MUHAMMAD ARFAN
name: FAROOQ AHMAD
name: HASSAN MUNIR
Publisher: name: Zenodo
Year: 2023
Subjects: L-Methionine, Dekalb Maize Hybrids, Bio-Stimulant, Amino Acid, Foliar Application, S-Adenosylmethionine (SAM).

description: Abstract
The world's arid and semi-arid regions are frequently subjected to significant abiotic stresses, particularly salt stress, which threaten crop yield and production. In light of this, the current study aimed to assess the mitigating effects of salinity stress through different doses of L-methionine (0, 50, and 100 mg L-1), with the goal of promoting sustainable production of Dekalb maize hybrids (Dk-6317 and Dk-9108). The experiment was carried out during spring 2020 in a pot setup, where salt stress was induced by applying two levels of sodium chloride (0 and 120 mM). Exogenous L-methionine at 50 mg L-1 and 100 mg L-1 significantly improved maize growth, yield, photosynthetic pigments, and antioxidant defence characteristics. Salt stress significantly (p ≤0.05) reduced plant height (17.89% and 21.40%), shoot fresh weight (17.13% and 17.42%), shoot dry weight (18.03% and 29.98%), root fresh weight (21.56% and 31.02%), root dry weight (33.37% and 30.51%), and leaf area (16.28% and 21.18%) of Dk-6317 and DK-9108, respectively, when compared to L-methionine treatments. Furthermore, correlation analysis revealed a significant (p ≤0.05) correlation between various studied traits, including enzymatic and stress-related antioxidants, as well as yield attributes. As a result, antioxidant enzyme activity such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) promotes plant growth by positively correlating with photosynthetic pigments, resulting in higher yield attributes. It appears that L-methionine improves maize crop development when subjected to salt exposure, a novel aspect of L-methionine's beneficial role. A beneficial interaction between L-methionine and photosynthetic pigments suggests its potential to mitigate salt toxicity effects and enhance sustainable maize production.
Symmetry-protected topological corner modes in a periodically driven interacting spin lattice
Creators: name: Koor, Kelvin
name: Bomantara, Raditya Weda
name: Kwek, Leong Chuan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Periodic driving has the longstanding reputation for generating exotic phases of matter with no static counterparts. This work explores the interplay among periodic driving, interaction effects, and $\mathbb{Z}_2$ symmetry that leads to the emergence of Floquet symmetry protected second-order topological phases in a simple but insightful two-dimensional spin-1/2 lattice. Through a combination of analytical and numerical treatments, we verify the formation of 0 and $π$ modes, i.e., corner localized $\mathbb{Z}_2$ symmetry broken operators that respectively commute and anticommute with the one-period time evolution operator. We further verify the topological nature of these modes by demonstrating their presence over a wide range of parameter values and explicitly deriving their associated topological invariants under special conditions. Finally, we propose a means to detect the signature of such modes in experiments and discuss the effect of imperfections.
description: 16 pages, 10 figures. Comments are most welcome
Anisotropic thermoreflectance thermometry: A contactless frequency-domain thermoreflectance approach to study anisotropic thermal transport
Creators: name: Pérez, Luis A.
name: Xu, Kai
name: Wagner, Markus R.
name: Dörling, Bernhard
name: Perevedentsev, Aleksandr
name: Goñi, Alejandro R.
name: Campoy-Quiles, Mariano
name: Alonso, M. Isabel
name: Reparaz, Juan Sebastián
Publisher: name: Technische Universität Berlin
Year: 2022
Subjects: subject: 530 Physik
subject: thin films
subject: thermodynamic properties
subject: temperature metrology
subject: thermal conductivity
subject: optical metrology
subject: thermal transport
subject: semiconductors
subject: lasers
subject: data processing

description: This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Pérez, L. A., Xu, K., Wagner, M. R., Dörling, B., Perevedentsev, A., Goñi, A. R., Campoy-Quiles, M., Alonso, M. I., & Reparaz, J. S. (2022). Anisotropic thermoreflectance thermometry: A contactless frequency-domain thermoreflectance approach to study anisotropic thermal transport. In Review of Scientific Instruments (Vol. 93, Issue 3, p. 034902). AIP Publishing and may be found at https://doi.org/10.1063/5.0066166.
description: We developed a novel contactless frequency-domain thermoreflectance approach to study thermal transport, which is particularly convenient when thermally anisotropic materials are considered. The method is based on a line-shaped heater geometry, produced with a holographic diffractive optical element, instead of using a spot heater as in conventional thermoreflectance. The heater geometry is similar to the one used in the 3-omega method, however, keeping all the technical advantages offered by non-contact methodologies. The present method is especially suitable to determine all the elements of the thermal conductivity tensor, which is experimentally achieved by simply rotating the sample with respect to the line-shaped optical heater. We provide the mathematical solution of the heat equation for the cases of anisotropic substrates, thin films, and multilayer systems. This methodology allows an accurate determination of the thermal conductivity and does not require complex modeling or intensive computational efforts to process the experimental data, i.e., the thermal conductivity is obtained through a simple linear fit (“slope method”), in a similar fashion to the 3-omega method. We demonstrate the potential of this approach by studying isotropic and anisotropic materials in a wide range of thermal conductivities. In particular, we have studied the following inorganic and organic systems: (i) glass, Si, and Ge substrates (isotropic), (ii) β-Ga2O3 and a Kapton substrate (anisotropic), and (iii) a 285 nm thick SiO2 thin film deposited on a Si substrate. The accuracy in the determination of the thermal conductivity is estimated as ≈5%, whereas the temperature uncertainty is ΔT ≈ 3 mK.
Study of 20-inch PMTs dark count generated large pulses
Creators: name: Zhang, Yu
name: Wang, Zhimn
name: Li, Min
name: Zhang, Yongpeng
name: Wang, Yaoguang
name: Peng, Zhaoyuan
name: Yang, Changgen
name: Heng, Yuekun
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The main goal of the JUNO experiment is to determine the neutrino mass ordering with a 20\,kt liquid-scintillator detector. The 20-inch PMT is crucial as one of JUNO key instruments to realize an excellent energy resolution of at least 3\,\% at 1\,MeV. The knowledge on PMT's characterisation and feature is critical for detector performance understanding. Large pulses from PMT dark count such as from flasher or others are one of the serious concerns for detector noise control. Focusing on the large pulses from 20-inch PMT dark count, this paper is trying to investigate the causes by measurements with a muon tagging system. It is found that the large pules of 20-inch PMT dark count is contributed mainly from muons hitting the PMT glass. A simulation is also realized and achieved a consistent understanding.
description: 22 pages, 20 figures
Cosmological constraints from the power spectrum and bispectrum of 21cm intensity maps
Creators: name: Karagiannis, Dionysios
name: Maartens, Roy
name: Randrianjanahary, Liantsoa
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The 21cm emission of neutral hydrogen is a potential probe of the matter distribution in the Universe after reionisation. Cosmological surveys of this line intensity will be conducted in the coming years by the SKAO and HIRAX experiments, complementary to upcoming galaxy surveys. We present the first forecasts of the cosmological constraints from the combination of the 21cm power spectrum and bispectrum. Fisher forecasts are computed for the constraining power of these surveys on cosmological parameters, the BAO distance functions and the growth function. We also estimate the constraining power on dynamical dark energy and modified gravity. Finally we investigate the constraints on the 21cm clustering bias, up to second order. We consider the effects on the 21cm correlators of the telescope beam, instrumental noise, foreground avoidance, the Alcock-Paczynski effect and theoretical errors in the modelling of the correlators. Adding Planck priors, and marginalising over nuisance parameters, HIRAX achieves sub-percent precision on the $Λ$CDM parameters, with SKAO delivering slightly lower precision. The modified gravity parameter $γ$ is constrained at 1% (HIRAX) and 5% (SKAO). For the dark energy parameters $w_0,w_a$, HIRAX delivers percent-level precision while SKAO constraints are weaker. HIRAX achieves sub-percent precision on the BAO distance functions $D_A,H$, while SKAO reaches 1-2% for $0.6\lesssim z\lesssim 1$. The growth rate $f$ is constrained at a few-percent level for the whole redshift range of HIRAX and for $0.6\lesssim z\lesssim 1$ by SKAO. The different performances arise mainly since HIRAX is a packed inteferometer that is optimised for BAO measurements, while SKAO is not optimised for interferometer cosmology and operates better in single-dish mode, where the telescope beam limits access to the smaller scales that are covered by an interferometer.
description: 37 pages, 6 figures, version accepted by JCAP
Optimal Tableaux Method for Constructive Satisfiability Testing and Model Synthesis in the Alternating-time Temporal Logic ATL+
Creators: name: Cerrito, Serenella
name: David, Amélie
name: Goranko, Valentin
Publisher: name: arXiv
Year: 2014
Subjects: subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences
subject: F.4.1; F.4.3
subject: 03B44, 68Q60

description: We develop a sound, complete and practically implementable tableaux-based decision method for constructive satisfiability testing and model synthesis in the fragment ATL+ of the full Alternating time temporal logic ATL*. The method extends in an essential way a previously developed tableaux-based decision method for ATL and works in 2EXPTIME, which is the optimal worst case complexity of the satisfiability problem for ATL+ . We also discuss how suitable parametrizations and syntactic restrictions on the class of input ATL+ formulae can reduce the complexity of the satisfiability problem.
description: 45 pages
PSYCHOLOGICAL METHODS OF EDUCATION AND DEVELOPMENT ACCORDING TO THE CHILD'S TEMPERAMENT
Creators: name: Nurqulova, Gavhar
name: Saydaliyeva, Mekhriniso
Publisher: name: Zenodo
Year: 2023

description: This article contains the individual psychological feature of the child - the general understanding of the temperature and the methods of educational methods of temperature technique. At the same time, misconceptions according to the child temperament is also covered.
title: Medienpädagogische Deutungsmuster von Lehrerinnen und Lehrern – Problemzentriertes Interview im Rahmen eines Grounded-Theory-Ansatzes
Creators: name: Dallmann, Christine
Publisher: name: Knaus, Thomas
Year: 2017

description: Lehrerinnen und Lehrer sind die zentralen Akteurinnen und Akteure schulischer Medienpädagogik. Vor diesem Hintergrund fragt das hier in Ausschnitten vorgestellte Forschungsvorhaben nach medienpädagogischen Deutungsmustern von Lehrerinnen und Lehrern, welche als ausschlaggebend für deren medienpädagogisches Handeln angenommen werden können und über als nötig erachtete (und verhältnismäßig häufig thematisierte) Qualifizierungen hinausgehen. Dem Forschungsvorhaben liegt ein Grounded-Theory-Ansatz mit seinen methodologischen Prämissen zu Grunde. Der Beitrag stellt den theoretischen Kontext und die Ziele des Forschungsvorhabens sowie die Methodologie der Grounded Theory Methodology kurz vor, um daran anschließend Erfahrungen mit der Forschungsmethode problemzentrierter Interviews im Zusammenhang mit der methodologischen Einbettung in einen solchen Ansatz sowie dessen methodische Verfahren zur Auswertung berichten und vor dem Hintergrund des theoretischen und methodologischen Ansatzes reflektieren zu können.
Microbuckling of Fibrin Provides a Mechanism for Cell Mechanosensing
Creators: name: Notbohm, Jacob
name: Lesman, Ayelet
name: Rosakis, Phoebus
name: Tirrell, David A.
name: Ravichandran, Guruswami
Publisher: name: arXiv
Year: 2014
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Biological cells sense and respond to mechanical forces, but how such a mechanosensing proccess takes place in a nonlinear inhomogeneous fibrous matrix remains unknown. We show that cells in a fibrous matrix induce deformation fields that propagate over a longer range than predicted by linear elasticity. Synthetic, linear elastic hydrogels used in many mechanotransduction studies fail to capture this effect. We develop a nonlinear microstructural finite element model for a fiber network to simulate localized deformations induced by cells. The model captures measured cell- induced matrix displacements from experiments and identifies an important mechanism for long range cell mechanosensing: loss of compression stiffness due to microbuckling of individual fibers. We show evidence that cells sense each other through the formation of localized intercellular bands of tensile deformations caused by this mechanism.
description: 11 pages, 6 figures. +14 pages supplementary material (+ 7 figures). Modified extensively after review
Choi matrices revisited
Creators: name: Kye, Seung-Hyeok
Publisher: name: arXiv
Year: 2022
Subjects: subject: Operator Algebras (math.OA)
subject: FOS: Mathematics

description: A linear map between matrix algebras corresponds to the Choi matrix in the tensor product of two matrix algebras, whose definition depends on the matrix units. Paulsen and Shultz [J. Math. Phys. {\bf 54} (2013), 072201] considered the question if one can replace matrix units by another basis of matrix algebras in the definition of Choi matrix to retain the correspondence between complete positivity of maps and positivity of Choi matrices, and gave a sufficient condition on basis under which this is true. In this note, we provide necessary and sufficient conditions, to see that the Paulsen--Shultz condition is also necessary.
description: No change. I am replacing the file, because I could not see PDF file due to some technical problems
On twisted N=2 5D super Yang-Mills theory
Creators: name: Qiu, Jian
name: Zabzine, Maxim
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Differential Geometry (math.DG)
subject: Symplectic Geometry (math.SG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: On a five dimensional simply connected Sasaki-Einstein manifold, one can construct Yang-Mills theories coupled to matter with at least two supersymmetries. The partition function of these theories localises on the contact instantons, however the contact instanton equations are not elliptic. It turns out that these equations can be embedded into the Haydys-Witten equations (which are elliptic) in the same way the 4D anti-self-dual instanton equations are embedded in the Vafa-Witten equations. We show that under some favourable circumstances, the latter equations will reduce to the former by proving some vanishing theorems. It was also known that the Haydys-Witten equations on product manifolds $M_5=M_4\times \mathbb{R}$ arise in the context of twisting the 5D maximally supersymmetric Yang-Mills theory. In this paper, we present the construction of twisted $N=2$ Yang-Mills theory on Sasaki-Einstein manifolds, and more generally on $K$-contact manifolds. The localisation locus of this new theory thus provides a covariant version of the Haydys-Witten equation.
description: 30 pages, the vanishing theorem is improved, refs added
X-ray and GeV-gamma-ray emission property of TeV Compact Symmetric Object PKS 1413+135 and Implication for Episodic Jet Activity
Creators: name: Gan, Ying-Ying
name: Zhang, Jin
name: Yao, Su
name: Zhang, Hai-Ming
name: Liang, Yun-Feng
name: Liang, En-Wei
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: PKS 1413+135, a compact symmetric object (CSO) with a two-side pc-scale structure in its miniature radio morphology, is spatially associated with 4FGL J1416.1+1320 and recently detected with MAGIC telescopes. We comprehensively analyze its X-ray and GeV gamma-ray observation data for revealing its high energy radiation physics. It is found that the source is in a low-flux stage before MJD 58500 and experiences violent outbursts after MJD 58500 in the GeV band. The flux at 10 GeV varies ~3 orders of magnitude, and the GeV-flux variation is accompanied by the clear spectral variation, which is characterized as a soft log-parabola spectrum in the low-flux state and a hard power-law spectrum in the bright flares. The variability amplitude of X-rays is lower than that of gamma-rays, and no correlation of variability between gamma-rays and X-rays is observed. Fitting the broadband spectral energy distribution during a GeV outburst with a multi-zone leptonic model, we show that the GeV gamma-rays are attributed to the external Compton process while the X-rays are hybrid of several components. The predicted TeV gamma-ray flux during the GeV outburst is consistent with the detection of MAGIC telescopes. These results, together with its CSO radio morphology, imply that PKS 1413+135 has the episodic nuclear jet activities. The weak gamma-ray emission before MJD 58500 may be from its sub-pc-/pc-scale jet component powered by previous activities, and the violent outbursts with short-timescale variability after MJD 58500 could be attributed to the recently restarted jet activity.
description: 16 pages, 4 figures, 3 tables, accepted for publication in ApJ
Ground states of 1D symmetry-protected topological phases and their utility as resource states for quantum computation
Creators: name: Prakash, Abhishodh
name: Wei, Tzu-Chieh
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The program of classifying symmetry protected topological (SPT) phases in 1D has been recently completed and has opened the doors to study closely the properties of systems belonging to these phases. It was recently found that being able to constrain the form of ground states of SPT order based on symmetry properties also allows to explore novel resource states for processing of quantum information. In this paper, we generalize the consideration of Else et al. [Phys. Rev. Lett. {\bf 108}, 240505 (2012)] where it was shown that the ground-state form of spin-1 chains protected by $\mathbb{Z}_2 \times \mathbb{Z}_2$ symmetry supports perfect operation of the identity gate, important also for long-distance transmission of quantum information. We develop a formalism to constrain the ground-state form of SPT phases protected by any arbitrary finite symmetry group and use it to examine examples of ground states of SPT phases protected by various finite groups for similar gate protections. We construct a particular Hamiltonian invariant under $A_4$ symmetry transformation which is one of the groups that allows protected identity operation and examine its ground states. We find that there is an extended region where the ground state is the AKLT state, which not only supports the identity gate but also arbitrary single-qubit gates.
description: 16 pages, 1 figure, revised version accepted in PRA
DESIGN AND DEVELOPMENT OF A REAL-TIME CYBER-PHYSICAL TESTBED FOR CYBERSECURITY RESEARCH
Creators: name: Theos, Vasileios
Publisher: name: Purdue University Graduate School
Year: 2023
Subjects: classificationCode: 401906
subject: Nuclear engineering (incl. fuel enrichment and waste processing and storage)
classificationCode: 460499
subject: Cybersecurity and privacy not elsewhere classified

description: Modern reactors promise enhanced capabilities not previously possible including integration with the smart grid, remote monitoring, reduced operation and maintenance costs, and more efficient operation. . Modern reactors are designed for installation to remote areas and integration to the electric smart grid, which would require the need for secure undisturbed remote control and the implementation of two-way communications and advanced digital technologies. However, two-way communications between the reactor facility, the enterprise network and the grid would require continuous operation data transmission. This would necessitate a deep understanding of cybersecurity and the development of a robust cybersecurity management plan in all reactor communication networks. Currently, there is a limited number of testbeds, mostly virtual, to perform cybersecurity research and investigate and demonstrate cybersecurity implementations in a nuclear environment. To fill this gap, the goal of this thesis is the development of a real-time cyber-physical testbed with real operational and information technology data to allow for cybersecurity research in a representative nuclear environment. In this thesis, a prototypic cyber-physical testbed was designed, built, tested, and installed in PUR-1. The cyber-physical testbed consists of an Auxiliary Moderator Displacement Rod (AMDR) that experimentally simulates a regulating rod, several sensors, and digital controllers mirroring Purdue University Reactor One (PUR-1) operation. The cyber-physical testbed is monitored and controlled remotely from the Remote Monitoring and Simulation Station (RMSS), located in another building with no line of sight to the reactor room. The design, construction and testing of the cyber-physical testbed are presented along with its capabilities and limitations. The cyber-physical testbed network architecture enables the performance of simulated cyberattacks including false data injection and denial of service. Utilizing the RMSS setup, collected information from the cyber-physical testbed is compared with real-time operational PUR-1 data in order to evaluate system response under simulated cyber events. Furthermore, a physics-based model is developed and benchmarked to simulate physical phenomena in PUR-1 reactor pool and provide information about reactor parameters that cannot be collected from reactor instrumentation system.
The universe in words: Astronomy for all through audio description within the outreach project Astroaccesible
Creators: name: Pérez-Montero, Enrique
name: Barnés-Castaño, Celia
name: Gómez-Caro, Emilio Garcí a
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Astroaccesible is an outreach project hosted by the Instituto de AstrofÍ sica de AndalucÍ a - CSIC and leaded by a blind astronomer aimed at the teaching and popularisation of astronomy and astrophysics among all kind of disabled and non-disabled people. Among the different strategies followed to transmit information to blind and partially sighted people, audio description is one of the most accesible and popular in the case of films and museums, but it has not been yet widely incorporated for the description of astronomical images. In this contribution we introduce {"The Universe in words", which are a series of videos describing images of some of the most popular objects in the Messier catalogue. These audio descriptions do not only have a clear inclusive aspect, but also imply a better and deeper understanding of the represented images for everybody. This is one of the most important aspects of using inclusive resources, as they also clearly improve the efficiency of the transmission process for all kind of public. These videos can also be used as supplementary material in of in-person activities and as a complement to other kind of materials, such as sonifications or models of the same or similar type of astronomical objects.
description: 4 pages. To appear as conference contribution to the 2nd IAU Workshop Beyond the Common Senses held on 2021
MEТОДИКА КОМПЛЕКСНОГО ИЗУЧЕНИЯ ТЕМЫ «РЕЦЕПТ» НА КАФЕДРАХ ЛАТИНСКОГО ЯЗЫКА И ФАРМАКОЛОГИИ .
Creators: name: Бекназарова, Мохия
Publisher: name: Zenodo
Year: 2023

description: Фармацевтический цикл занимает особое положение на курсе латинского языка. Его целесообразно начинать с тем «Глагол» и Рецепт».
Qubit state transfer via discrete-time quantum walks
Creators: name: Yalçınkaya, İ.
name: Gedik, Z.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose a scheme for perfect transfer of an unknown qubit state via the discrete-time quantum walk on a line or a circle. For this purpose, we introduce an additional coin operator which is applied at the end of the walk. This operator does not depend on the state to be transferred. We show that perfect state transfer over an arbitrary distance can be achieved only if the walk is driven by an identity or a flip coin operator. Other biased coin operators and Hadamard coin allow perfect state transfer over finite distances only. Furthermore, we show that quantum walks ending with a perfect state transfer are periodic.
description: 13 pages, 5 figures
Quantized Nonlinear Transport with Ultracold Atoms
Creators: name: Yang, Fan
name: Zhai, Hui
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this letter, we propose how to measure the quantized nonlinear transport using two-dimensional ultracold atomic Fermi gases in a harmonic trap. This scheme requires successively applying two optical pulses in the left and lower half-planes and then measuring the number of extra atoms in the first quadrant. In ideal situations, this nonlinear density response to two successive pulses is quantized, and the quantization value probes the Euler characteristic of the local Fermi sea at the trap center. We investigate the practical effects in experiments, including finite pulse duration, finite edge width of pulses, and finite temperature, which can lead to deviation from quantization. We propose a method to reduce the deviation by averaging measurements performed at the first and third quadrants, inspired by symmetry considerations. With this method, the quantized nonlinear response can be observed reasonably well with experimental conditions readily achieved with ultracold atoms.
description: 7 pages, 3 figures, expanded introduction, added an appendix, added new references, accepted by Quantum
Strongly interacting Rydberg excitons in Cu2O
Creators: name: Heckötter, Julian
Publisher: name: Technische Universität Dortmund
Year: 2020
Subjects: subject: Rydberg excitons
subject: Semiconductor physics
subject: 530
subject: Exziton
subject: Absorptionsspektroskopie
subject: Elektron-Loch-Plasma
subject: Halbleiterphysik

description: Excitons are fundamental electronic excitations in a semiconductor. They are bound states consisting of an electron in the conduction band and a positively charged hole in the valence band. They have hydrogen-like properties and are therefore referred to as the hydrogen analogues in solid states. In the semiconductor Cuprous Oxide, Cu2O, highly excited states of excitons can be observed with principal quantum numbers up to n = 25. These states are called Rydberg excitons in analogy to their atomic counterparts, the Rydberg atoms. The intention of this thesis is to gain new insights into fundamental properties of these Rydberg excitons by optical spectroscopy. The focus lies on one-photon absorption spectroscopy with high spectral resolution up to 5 nanoelectronvolts. The physics addressed in this thesis can be divided into three main topics. First, the interaction of Rydberg excitons with high principal quantum numbers n with both external electric and magnetic fields is studied. In the regime of high n, the density of states becomes so large that it becomes unfeasible to use a microscopic theory that explicitly considers every single state. Instead, general n-dependent scaling laws for various fundamental properties of Rydberg excitons are derived theoretically and proven experimentally. These scaling laws provide an efficient description of Rydberg excitons in the high-n regime and give fundamental insights into similarities and differences between Rydberg excitons and Rydberg atoms. Second, the behavior of Rydberg excitons surrounded by an electron-hole plasma is investigated. For this purpose, absorption spectra are presented, recorded at different densities of free carriers injected into the crystal by an off-resonant pump laser. Carrier densities as low as 0.01 µm−3 are found to lead to a lowering of the band gap and the disappearance of the highest exciton lines. A model based on screening of the Coulomb interaction by free charge carriers is presented that allows for a phenomenological description of the data. In this context, the experimental parameter space spanned by excitation power and temperature is investigated to determine the limiting factors for the observation of Rydberg excitons with principal quantum numbers higher than n = 25, the highest Rydberg exciton state observed so far. Indeed, at nanowatt laser powers and millikelvin temperatures, the extension of the observable exciton series to n = 28 is possible. The third part of this thesis addresses mutual interactions between Rydberg excitons. Combining data from pump-probe experiments with a detailed theoretical model for the shape of these spectra for several exciton interaction mechanisms clearly shows that long-range van der Waals-type interactions are the dominant contribution to interactions between Rydberg excitons.
Meridional composite pulses for low-field magnetic resonance
Creators: name: Bodenstedt, Sven
name: Mitchell, Morgan W.
name: Tayler, Michael C. D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We discuss procedures for error-tolerant spin control in environments that permit transient, large-angle reorientation of magnetic bias field. Short sequences of pulsed, non-resonant magnetic field pulses in a laboratory-frame meridional plane are derived. These are shown to have band-pass excitation properties comparable to established amplitude-modulated, resonant pulses used in high, static-field magnetic resonance. Using these meridional pulses, we demonstrate robust $z$ inversion in proton ($^{1}$H) nuclear magnetic resonance near earth's field.
description: 4 figures. Supplemental Material as PDF
Segmental Refinement: A Multigrid Technique for Data Locality
Creators: name: Adams, Mark F.
name: Brown, Jed
name: Knepley, Matt
name: Samtaney, Ravi
Publisher: name: arXiv
Year: 2014
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: We investigate a domain decomposed multigrid technique, segmental refinement, for solving general nonlinear elliptic boundary value problems. Brandt and Diskin first proposed this method in 1994; we continue this work by analytically and experimentally investigating its complexity. We confirm that communication of traditional parallel multigrid can be eliminated on fine grids with modest amounts of extra work and storage while maintaining the asymptotic exactness of full multigrid, although we observe a dependence on an additional parameter not considered in the original analysis. We present a communication complexity analysis that quantifies the communication costs ameliorated by segmental refinement and report performance results with up to 64K cores of a Cray XC30.
Cannibal dark matter decoupled from standard model: cosmological constraints
Creators: name: Ghosh, Avirup
name: Gope, Sourav
name: Mukhopadhyay, Satyanarayan
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: An internally thermalized dark matter (DM) with only gravitational interaction with the standard model (SM) particles at low temperatures, may undergo number-changing self-scatterings in the early Universe, eventually freezing out to the observed DM abundance. If these reactions, such as a $3 \rightarrow 2$ process, take place when the DM is non-relativistic, DM cannibalizes itself to cool much slower than standard non-relativistic matter during the cannibal phase. As shown in earlier studies, if the cannibal phase takes place during the matter-dominated epoch, there are very strong constraints from structure formation. Considering scenarios in which the cannibal phase freezes out in the radiation-dominated epoch instead, we show that cannibal DM decoupled from the SM can be viable, consistent with all present cosmological constraints. To this end, we solve the coupled evolution equations of the DM temperature and density, and determine its abundance for different DM self-couplings. We then evaluate the constraints on these parameters from the cosmic-microwave background power spectrum, the big-bang nucleosynthesis limits on the relativistic degrees of freedom, the Lyman-$α$ limits on the DM free-streaming length and the theoretical upper bound on the $3 \rightarrow 2$ annihilation rate from $S-$matrix unitarity. We find that depending upon the DM self-couplings, a scalar cannibal DM with mass in the range of around 80 eV to 700 TeV can make up the observed DM density and satisfy all the constraints, when the initial DM temperature ($T_{\rm DM}$) is lower than the SM one ($T_{\rm SM}$), with $T_{\rm SM}/9100 \lesssim T_{\rm DM} \lesssim \,T_{\rm SM}/1.1$.
description: 22 pages, 11 figures; v3: results corrected, figures and text updated, version to appear in PRD
Populismus 2.0?
Creators: name: Froböse, Lars
Publisher: name: Universitätsbibliothek Siegen
Year: 2020
Subjects: subject: 320 Politik
subject: Social Media
subject: Populismus
subject: Twitter
subject: Diskursanalyse
subject: Populismus
subject: Social Media
subject: Twitter
subject: Polarisierung

description: In Zeiten von twitternden US-Präsidenten, Shitstorms, Cybermobbing und Fake-News, verbreitet über die beinahe omnipräsenten sozialen Medien, fällt die politische Meinungsbildung zunehmend schwerer. Erst recht, wenn Politiker die neuen Möglichkeiten ungefilterter, beliebig skalierbarer Online-Kommunikation für populistische Agitation nutzen. Die vorliegende Publikation geht der Frage nach, ob soziale Medien Populismus befördern und damit die Polarisierung politischer Diskurse begünstigen. Dafür wird die Twitter-Kommunikation aller Bundestagsabgeordneten im Vorfeld der Europawahl 2019 mittels kritischer Diskursanalyse nach Siegfried Jäger (2012) untersucht, wobei das Untersuchungsinstrument um ein neu entwickeltes, auf soziale Medien zugeschnittenes Analyseinstrument zur Erkennung von Elementen des populistischen Diskurses erweitert wird.
title: Summary Documentation for the IRIS UMETRICS 2022 Data Release
Creators: name: Nicholls, Natsuko
name: Brown, Christopher
name: Ku, Raphael Lesmond
name: Owen-Smith, Jason
Publisher: name: Institute for Research on Innovation and Science (IRIS)
Year: 2022

description: This is a publicly available summary of the full data documentation, providing project and data descriptions for the IRIS UMETRICS 2022 Data Release.
Yang-Mills solutions on Minkowski space via non-compact coset spaces
Creators: name: Kumar, Kaushlendra
name: Lechtenfeld, Olaf
name: Costa, Gabriel Picanço
name: Röhrig, Jona
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We find a two-parameter family of solutions of the Yang-Mills equations for gauge group SO(1,3) on Minkowski space by foliating different parts of it with non-compact coset spaces with SO(1,3) isometry. The interior of the lightcone is foliated with hyperbolic space $H^3\cong \text{SO}(1,3)/\text{SO}(3)$, while the exterior of the lightcone employs de Sitter space dS$_3\cong \text{SO}(1,3)/\text{SO}(1,2)$. The lightcone itself is parametrized by SO(1,3)/ISO(2) in a nilpotent fashion. Equivariant reduction of the SO(1,3) Yang-Mills system on the first two coset spaces yields a mechanical system with inverted double-well potential and the foliation parameter serving as an evolution parameter. Its known analytic solutions are periodic or runaway except for the kink. On the lightcone, only the vacuum solution remains. The constructed Yang-Mills field strength is singular across the lightcone and of infinite action due to the noncompact cosets. Its energy-momentum tensor takes a very simple form, with energy density of opposite signs inside and outside the lightcone.
description: 1+11 pages, 3 diagrams in 2 figures
A Dark Energy Model in Kaluza-Klein Cosmology
Creators: name: Mukhopadhyay, Utpal
name: Chakraborty, Ipsita
name: Ray, Saibal
name: Usmani, A. A.
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: We study a dynamic $Λ$ model with varying gravitational constant $G$ under the Kaluza-Klein cosmology. Physical features and the limitations of the present model have been explored and discussed. Solutions are found mostly in accordance with the observed features of the accelerating universe. Interestingly, signature flipping of the deceleration parameter is noticed and the present age of the Universe is also attainable under certain stringent conditions. We find that the time variation of gravitational constant is not permitted without vintage $Λ$.
description: 9 pages, 5 figures, Accepted in International Journal of Theoretical Physics
Anisotropy and characteristic scales in halo density gradient profiles
Creators: name: Wang, X.
name: Wang, H.
name: Mo, H. J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We use a large N-body simulation to study the characteristic scales in the density gradient profiles in and around halos with masses ranging from $10^{12}$ to $10^{15} h^{-1}{\rm M_\odot}$. We investigate the profiles separately along the major (T_1) and minor (T_3) axes of the local tidal tensor and how the characteristic scales depend on halo mass, formation time, and environment. We find two kinds of prominent characteristic features in the gradient profiles, a deep `valley' and a prominent `peak'. We use the Gaussian Process Regression to fit the gradient profiles and identify the local extrema to determine the scales associate with these features. Around the valley, we identify three types of distinct local minima, corresponding to caustics of particles orbiting around halos. The appearance and depth of the three caustics depend significantly on the direction defined by the local tidal field, formation time and environment of halos. The first caustic is located at a radius r>0.8R_{200}, corresponding to the splashback feature, and is dominated by particles at their first apocenter after infall. The second and third caustics, around 0.6R_{200} and 0.4R_{200} respectively, can be determined reliably only for old halos. The first caustic is always the most prominent feature along T_3, but may not be the case along T_1 or in azimuthally-averaged profiles, suggesting that caution must be taken when using averaged profiles to investigate the splashback radius. We find that the splashback feature is approximately isotropic when proper separations are made between the first and the other caustics. We also identify a peak feature located at $\sim$ 2.5R_{200} in the density gradient profile. This feature is the most prominent along T_1 and is produced by mass accumulations from the structure outside halos. We also discuss the origins of these features and their observational implications.
description: 15 pages, 12 figures, accepted by A&A
Gauge invariant formulation of 3$γ$ decay of particle-antiparticle bound states
Creators: name: Blankleider, B.
name: Kvinikhidze, A. N.
name: Silagadze, Z. K.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We construct the gauge invariant three-photon decay amplitude of particle-antiparticle bound states modeled by the Dyson-Schwinger and Bethe-Salpeter equations. Application to the quark-antiquark ($q\bar{q}$) bound states is emphasized. An essential aspect of our formulation is that it applies to any underlying quantum field theoretic model of the $q\bar{q}$ system, and not just to models, like exact QCD, where the quark self-energy $Σ$ couples to the electromagnetic field solely via dressed quark propagators. In this way, applications to effective field theories and other QCD motivated models are envisioned. The three-photon decay amplitude is constructed by attaching currents to all possible places in the Feynman diagrams contributing to the dressed quark propagator. The gauge invariance of our construction is thus a direct consequence of respecting the underlying structure of the quantum field theory determining the dynamics. In the resultant expression for the three-photon decay amplitude, all the basic ingredients consisting of the bound state wave function, the final-state interaction $q\bar{q}$ $t$ matrix, the dressed quark propagator, and dressed quark currents, are determined by a universal Bethe-Salpeter kernel.
description: 33 pages, 11 figures, version accepted for publication in Phys Rev D
FLEXURAL BEHAVIOR OF TWO-LAYER BEAM MADE WITH LIGHT WEIGHT STEEL FIBRE CONCRETE AND RECYCLED AGGREGATE CONCRETE
Creators: name: WADHAH M. TAWFEEQ
name: AHMED W. AL ZAND
name: MALEK AL-RUSHDI
name: SALEH MAZEN
name: ABDUL AZIZ AL-BADI
name: HAMDAN AL JABRI
Publisher: name: Zenodo
Year: 2023
Subjects: Light-Weight Concrete, Flexural, Recycled Aggregate, Two-Layer Beam, Displacement, Fiber.

description: Abstract
In structural design, it is extremely desirable to use as low-material as possible while keeping integrity and usefulness. Reducing the structure's weight is one strategy for achieving this objective. Steel fibres have recently been added to reinforced concrete beams to increase flexural and shear strength. Fibre reinforcement in structural elements has drawn considerable interest from the building sector. Steel fibre has received the greatest attention and utilization among all fibre types. When compared to plain concrete, incorporating fibres into concrete may result in better crack management and greater strength. This study examines how two-layer beams made of lightweight steel fibre concrete and recycled aggregate concrete flex under bending loads. Twelve distinct beams with cross sections measuring 100 mm, 150 mm, and 1500 mm (width, depth, and length) are prepared and tested as part of the study. These beams are evaluated under four-point bending. In the tension zone of the lightweight concrete layer, different percentages of steel fibre ranging from 0% to 1.5% by volume were introduced. In the concrete compression layer, recycled block aggregate was substituted for natural coarse aggregate in varying percentages (0%, 25%, and 50%). According to the findings, the flexural strength of beams with a higher steel fibre percentage is higher than that of beams with a higher recycled aggregate component. The study also shows that two-layer beams with higher steel fibre content have superior crack management and deflection behavior than those with lower steel content. The results of the flexural reinforced concrete beam test were contrasted with the calculated design strength determined using British Standards.