cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Effects of Dark Energy Perturbations on Cosmological Tests of General Relativity
Creators: name: Dossett, Jason
name: Ishak, Mustapha
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Cosmological tests to distinguish between dark energy (DE) and modifications to gravity are a promising route to obtain clues on the origin of cosmic acceleration. We study here the robustness of these tests to the presence of DE density, velocity, and anisotropic stress perturbations. We find that the dispersion in the growth index parameter remains small enough to distinguish between extreme cases of DE models and some commonly used modified gravity models. The sign of the slope parameter for a redshift dependent growth index was found to be inconsistent as an additional test in extreme cases of DE models with perturbations. Next, we studied the effect of DE perturbations on the modified growth (MG) parameters that enter the perturbed Einstein equations. We find that while the dark energy perturbations affect the MG parameters, the deviations remain smaller than those due to modified gravity models. Additionally, the deviations due to DE perturbations with a non-zero effective sound speed occur at scale ranges that are completely different than those due to some modified gravity models such as the $f(R)$ models. In the case of modified gravity models with zero anisotropic stress at late times, the simultaneous determination of the effective dark energy equation of state and the MG parameters can provide the distinction between these models and DE. The growth index test was found to be the most robust to these perturbations. The scale dependence of the MG parameters in some cases of modified gravity constitute a clear-cut discriminant regardless of any DE perturbations. In summary, we find that the currently proposed cosmological tests to distinguish between DE and modified gravity are robust to DE perturbations even for extreme cases. This is certainly the case even for DE models with equations of state of DE that fall well outside of current cosmological constraints.
description: 18 pages, 15 figures. To appear in Phys.Rev.D
"param_card.SM.TT.2stepTN2.dat" of "Search for squarks and gluinos in final states with same-sign leptons and jets using 139 fb$^{-1}$ of data collected with the ATLAS detector"
Creators: name: ATLAS Collaboration
Publisher: name: HEPData
Year: 2020

description: SLHA file listing the superpartner masses and decay channels for the signal scenario showed in Figure 1b
description: A search for supersymmetric partners of gluons and quarks is presented, involving signatures with jets and either two isolated leptons ($e$ or $\mu$) with the same electric charge, or at least three isolated leptons. The analysis also relies on $b$-tagged jets or missing transverse momentum to extend its sensitivity. A data sample of proton--proton collisions at $\sqrt{s}$ = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to a total integrated luminosity of 139 fb$^{-1}$, is used for the search. No significant excess over the Standard Model expectation is observed. The results are interpreted in simplified supersymmetric models featuring both $R$-parity conservation and $R$-parity violation, extending the exclusion limits from previous searches up to 1600 GeV for gluino masses and 750 GeV bottom and top squark masses in these scenarios.
"param_card.SM.GG.2stepWZ.dat" of "Search for squarks and gluinos in final states with same-sign leptons and jets using 139 fb$^{-1}$ of data collected with the ATLAS detector"
Creators: name: ATLAS Collaboration
Publisher: name: HEPData
Year: 2020

description: SLHA file listing the superpartner masses and decay channels for the signal scenario showed in Figure 1c
description: A search for supersymmetric partners of gluons and quarks is presented, involving signatures with jets and either two isolated leptons ($e$ or $\mu$) with the same electric charge, or at least three isolated leptons. The analysis also relies on $b$-tagged jets or missing transverse momentum to extend its sensitivity. A data sample of proton--proton collisions at $\sqrt{s}$ = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to a total integrated luminosity of 139 fb$^{-1}$, is used for the search. No significant excess over the Standard Model expectation is observed. The results are interpreted in simplified supersymmetric models featuring both $R$-parity conservation and $R$-parity violation, extending the exclusion limits from previous searches up to 1600 GeV for gluino masses and 750 GeV bottom and top squark masses in these scenarios.
"SameSignThreeLepton2019.cxx" of "Search for squarks and gluinos in final states with same-sign leptons and jets using 139 fb$^{-1}$ of data collected with the ATLAS detector"
Creators: name: ATLAS Collaboration
Publisher: name: HEPData
Year: 2020

description: pseudocode illustrating the event and object selections for all the signal regions
description: A search for supersymmetric partners of gluons and quarks is presented, involving signatures with jets and either two isolated leptons ($e$ or $\mu$) with the same electric charge, or at least three isolated leptons. The analysis also relies on $b$-tagged jets or missing transverse momentum to extend its sensitivity. A data sample of proton--proton collisions at $\sqrt{s}$ = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to a total integrated luminosity of 139 fb$^{-1}$, is used for the search. No significant excess over the Standard Model expectation is observed. The results are interpreted in simplified supersymmetric models featuring both $R$-parity conservation and $R$-parity violation, extending the exclusion limits from previous searches up to 1600 GeV for gluino masses and 750 GeV bottom and top squark masses in these scenarios.
Controlled lasing from active optomechanical resonators
Creators: name: Czerniuk, T.
name: Brueggemann, C.
name: Tepper, J.
name: Brodbeck, S.
name: Schneider, C.
name: Kamp, M.
name: Hoefling, S.
name: Glavin, B. A.
name: Yakovlev, D. R.
name: Akimov, A. V.
name: Bayer, M.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Planar microcavities with distributed Bragg reflectors (DBRs) host, besides confined optical modes, also mechanical resonances due to stop bands in the phonon dispersion relation of the DBRs. These resonances have frequencies in the sub-terahertz (10E10-10E11 Hz) range with quality factors exceeding 1000. The interaction of photons and phonons in such optomechanical systems can be drastically enhanced, opening a new route toward manipulation of light. Here we implemented active semiconducting layers into the microcavity to obtain a vertical-cavity surface-emitting laser (VCSEL). Thereby three resonant excitations -photons, phonons, and electrons- can interact strongly with each other providing control of the VCSEL laser emission: a picosecond strain pulse injected into the VCSEL excites long-living mechanical resonances therein. As a result, modulation of the lasing intensity at frequencies up to 40 GHz is observed. From these findings prospective applications such as THz laser control and stimulated phonon emission may emerge.
More mathematics for pseudo-bosons
Creators: name: Bagarello, Fabio
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We propose an alternative definition for pseudo-bosons. This simplifies the mathematical structure, minimizing the required assumptions. Some physical examples are discussed, as well as some mathematical results related to the biorthogonal sets arising out of our framework.
Negative-mass exciton polaritons induced by dissipative light-matter coupling in an atomically thin semiconductor
Creators: name: Wurdack, M.
name: Yun, T.
name: Katzer, M.
name: Truscott, A. G.
name: Knorr, A.
name: Selig, M.
name: Ostrovskaya, E. A.
name: Estrecho, E.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Dispersion engineering is a powerful and versatile tool that can vary the speed of light signals and induce negative-mass effects in the dynamics of particles and quasiparticles. Here, we show that dissipative coupling between bound electron-hole pairs (excitons) and photons in an optical microcavity can lead to the formation of exciton polaritons with an inverted dispersion of the lower polariton branch and hence a negative mass. We perform direct measurements of the anomalous dispersion in atomically thin (monolayer) WS$_2$ crystals embedded in planar microcavities and demonstrate that the propagation direction of the negative-mass polaritons is opposite to their momentum. Our study introduces a new concept of non-Hermitian dispersion engineering for exciton polaritons and opens a pathway for realising new phases of quantum matter in a solid state.
description: 16 pages, 13 figures
Wireless energy transfer between anisotropic metamaterials shells
Creators: name: Diaz-Rubio, Ana
name: Carbonell, Jorge
name: Sanchez-Dehesa, Jose
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The behavior of strongly coupled Radial Photonic Crystals shells is investigated as a potential alternative to transfer electromagnetic energy wirelessly. These sub-wavelength resonant microstructures, which are based on anisotropic metamaterials, can produce efficient coupling phenomena due to their high quality factor. A configuration of selected constitutive parameters (permittivity and permeability) is analyzed in terms of its resonant characteristics. The coupling to loss ratio between two coupled resonators is calculated as a function of distance, the maximum (in excess of 300) is obtained when the shells are separated by three times their radius. Under practical conditions an 83% of maximum power transfer has been also estimated.
description: submitted to Annals of Physics
Disorder Induced Anomalous Hall Effect in Type-I Weyl Metals: Connection between the Kubo-Streda Formula in the Spin and Chiral basis
Creators: name: Zhang, Jia-Xing
name: Wang, Zhi-Yuan
name: Chen, Wei
Publisher: name: arXiv
Year: 2022
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We study the anomalous Hall effect (AHE) in tilted Weyl metals with weak Gaussian disorder under the Kubo-Streda formalism in this work. To separate the three different contributions, namely the intrinsic, side jump and skew scattering contribution, it is usually considered necessary to go to the eigenstate (chiral) basis of the Kubo-Streda formula. However, it is more straight-forward to compute the total Hall current in the spin basis. For the reason, we develop a systematic and transparent scheme to separate the three different contributions in the spin basis for relativistic systems by building a one-to-one correspondence between the Feynman diagrams of the different mechanisms in the chiral basis and the products of the symmetric and anti-symmetric part of the polarization operator in the spin basis. We obtain the three contributions of the AHE in tilted Weyl metals by this scheme and found that the side jump contribution exceeds both the intrinsic and skew scattering contribution for the low-energy effective Hamiltonian. We compared the anomalous Hall current obtained from our scheme with the results from the semi-classical Boltzmann equation approach under the relaxation time approximation and found that the results from the two approaches agree with each other in the leading order of the tilting velocity.
Mobility unevenness in rock-paper-scissors models
Creators: name: Menezes, J.
name: Rodrigues, S.
name: Batista, S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Pattern Formation and Solitons (nlin.PS)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: We investigate a tritrophic system whose cyclic dominance is modelled by the rock-paper-scissors game. We consider that organisms of one or two species are affected by movement limitations, which unbalances the cyclic spatial game. Performing stochastic simulations, we show that mobility unevenness controls the population dynamics. In the case of one slow species, the predominant species depends on the level of mobility restriction, with the slow species being preponderant if the mobility limitations are substantial. If two species face mobility limitations, our outcomes show that being higher dispersive does not constitute an advantage in terms of population growth. On the contrary, if organisms move with higher mobility, they expose themselves to enemies more frequently, being more vulnerable to being eliminated. Finally, our findings show that biodiversity benefits in regions where species are slowed. Biodiversity loss for high mobility organisms, common to cyclic systems, may be avoided with coexistence probability being higher for robust mobility limitations. Our results may help biologists understand the dynamics of unbalanced spatial systems where organisms' dispersal is fundamental to biodiversity conservation.
description: 7 pages, 7 figures
Prime Factorization of ideals in commutative rings, with a focus on Krull rings
Creators: name: Chang, Gyu Whan
name: Oh, Jun Seok
Publisher: name: arXiv
Year: 2022
Subjects: subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 13A15, 13B25, 13E05, 13F05

description: Let $R$ be a commutative ring with identity. The structure theorem says that $R$ is a PIR (resp., UFR, general ZPI-ring, $π$-ring) if and only if $R$ is a finite direct product of PIDs (resp., UFDs, Dedekind domains, $π$-domains) and special primary rings. All of these four types of integral domains are Krull domains, so motivated by the structure theorem, we study the prime factorization of ideals in a ring that is a finite direct product of Krull domains and special primary rings. Such a ring will be called a general Krull ring. It is known that Krull domains can be characterized by the star operations $v$ or $t$ as follows: An integral domain $R$ is a Krull domain if and only if every nonzero proper principal ideal of $R$ can be written as a finite $v$- or $t$-product of prime ideals. However, this is not true for general Krull rings. In this paper, we introduce a new star operation $u$ on $R$, so that $R$ is a general Krull ring if and only if every proper principal ideal of $R$ can be written as a finite $u$-product of prime ideals. We also study several ring-theoretic properties of general Krull rings including Kaplansky-type theorem, Mori-Nagata theorem, Nagata rings, and Noetherian property.
description: To appear in J. Korean Math. Soc
The nature and nurture of network evolution
Creators: name: Zhou, Bin
name: Holme, Petter
name: Gong, Zaiwu
name: Zhan, Choujun
name: Huang, Yao
name: Lu, Xin
name: Meng, Xiangyi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: Although the origin of the fat-tail characteristic of the degree distribution in complex networks has been extensively researched, the underlying cause of the degree distribution characteristic across the complete range of degrees remains obscure. Here, we propose an evolution model that incorporates only two factors: the node's weight, reflecting its innate attractiveness (nature), and the node's degree, reflecting the external influences (nurture). The proposed model provides a good fit for degree distributions and degree ratio distributions of numerous real-world networks and reproduces their evolution processes. Our results indicate that the nurture factor plays a dominant role in the evolution of social networks. In contrast, the nature factor plays a dominant role in the evolution of non-social networks, suggesting that whether nodes are people determines the dominant factor influencing the evolution of real-world networks.
description: 8pages, 4 figures
Complete ZX-calculi for the stabiliser fragment in odd prime dimensions
Creators: name: Booth, Robert I.
name: Carette, Titouan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We introduce a family of ZX-calculi which axiomatise the stabiliser fragment of quantum theory in odd prime dimensions. These calculi recover many of the nice features of the qubit ZX-calculus which were lost in previous proposals for higher-dimensional systems. We then prove that these calculi are complete, i.e. provide a set of rewrite rules which can be used to prove any equality of stabiliser quantum operations. Adding a discard construction, we obtain a calculus complete for mixed state stabiliser quantum mechanics in odd prime dimensions, and this furthermore gives a complete axiomatisation for the related diagrammatic language for affine co-isotropic relations.
description: 23 pages + 31 pages of references and appendices; more corrections
"param_card.SM.GG.Rpvlampp331.dat" of "Search for squarks and gluinos in final states with same-sign leptons and jets using 139 fb$^{-1}$ of data collected with the ATLAS detector"
Creators: name: ATLAS Collaboration
Publisher: name: HEPData
Year: 2020

description: SLHA file listing the superpartner masses and decay channels for the signal scenario showed in Figure 1d
description: A search for supersymmetric partners of gluons and quarks is presented, involving signatures with jets and either two isolated leptons ($e$ or $\mu$) with the same electric charge, or at least three isolated leptons. The analysis also relies on $b$-tagged jets or missing transverse momentum to extend its sensitivity. A data sample of proton--proton collisions at $\sqrt{s}$ = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to a total integrated luminosity of 139 fb$^{-1}$, is used for the search. No significant excess over the Standard Model expectation is observed. The results are interpreted in simplified supersymmetric models featuring both $R$-parity conservation and $R$-parity violation, extending the exclusion limits from previous searches up to 1600 GeV for gluino masses and 750 GeV bottom and top squark masses in these scenarios.
Ab initio melting temperatures of bcc and hcp iron under the Earth's inner core condition
Creators: name: Sun, Yang
name: Mendelev, Mikhail I.
name: Zhang, Feng
name: Liu, Xun
name: Da, Bo
name: Wang, Cai-Zhuang
name: Wentzcovitch, Renata M.
name: Ho, Kai-Ming
Publisher: name: arXiv
Year: 2022
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: There has been a long debate on the stable phase of iron under the Earth's inner core conditions. Because of the solid-liquid coexistence at the inner core boundary, the thermodynamic stability of solid phases directly relates to their melting temperatures, which remains considerable uncertainty. In the present study, we utilized a semi-empirical potential fitted to high-temperature ab initio data to perform a thermodynamic integration from classical systems described by this potential to ab initio systems. This method provides a smooth path for thermodynamic integration and significantly reduces the uncertainty caused by the finite-size effect. Our results suggest the hcp phase is the stable phase of pure iron under the inner core conditions, while the free energy difference between the hcp and bcc phases is tiny, on the order of 10s meV/atom near the melting temperature.
description: 4 figures
A New Versatile Code for Gamma-Ray Monte-Carlo Radiative Transfer
Creators: name: Leung, Shing-Chi
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Ongoing MeV telescopes such as INTEGRAL/SPI and Fermi/GBM, and proposed telescopes including the recently accepted COSI and the e-ASTROGAM and AMEGO missions, provide another window in understanding transients. Their signals contain information about the stellar explosion mechanisms and their corresponding nucleosynthesis of short-lived radioactive isotopes. This raises the need of a radiative transfer code which may efficiently explore different types of astrophysical $γ$-ray sources and their dependence on model parameters and input physics. In view of this, we present our new Monte-Carlo Radiative Transfer code in Python. The code synthesizes the $γ$-ray spectra and light curves suitable for modeling supernova ejecta, including C+O novae, O+Ne novae, Type Ia and core-collapse supernovae. We test the code extensively for reproducing results consistent with analytic models. We also compare our results with similar models in the literature and discuss how our code depends on selected input physics and setting.
description: 15 pages, 25 figures, published in the Monthly Notices of the Royal Astronomical Society, submitted at 08 May 2022, accepted at 14 Feb 2023, published at 20 Feb 2023
Spin-Orbit Enhanced Superconductivity in Bernal Bilayer Graphene
Creators: name: Zhang, Yiran
name: Polski, Robert
name: Thomson, Alex
name: Lantagne-Hurtubise, Étienne
name: Lewandowski, Cyprian
name: Zhou, Haoxin
name: Watanabe, Kenji
name: Taniguchi, Takashi
name: Alicea, Jason
name: Nadj-Perge, Stevan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: In the presence of a large perpendicular electric field, Bernal-stacked bilayer graphene (BLG) features several broken-symmetry metallic phases as well as magnetic-field-induced superconductivity. The superconducting state is quite fragile, however, appearing only in a narrow window of density and with a maximum critical temperature $T_c\approx30$~mK. Here, we show that placing monolayer tungsten diselenide (WSe$_{2}$) on BLG promotes Cooper pairing to an extraordinary degree: superconductivity appears at zero magnetic field, exhibits an order of magnitude enhancement in $T_c$, and occurs over a density range that is wider by a factor of eight. By mapping quantum oscillations in BLG-WSe$_2$ as a function of electric field and doping, we establish that superconductivity emerges throughout a region whose normal state is polarized, with two out of four spin-valley flavours predominantly populated. In-plane magnetic field measurements further reveal a striking dependence of the critical field on doping, with the Chandrasekhar-Clogston (Pauli) limit roughly obeyed on one end of the superconducting dome yet sharply violated on the other. Moreover, the superconductivity arises only for perpendicular electric fields that push BLG hole wavefunctions towards WSe$_2$ -- suggesting that proximity-induced (Ising) spin-orbit coupling plays a key role in enhancing the pairing. Our results pave the way for engineering robust, highly tunable, and ultra-clean graphene-based superconductors.
description: main text and supplementary information
A simple solution to the problem of self-assembling cubic diamond crystals
Creators: name: Rovigatti, Lorenzo
name: Russo, John
name: Romano, Flavio
name: Matthies, Michael
name: Kroc, Lukáš
name: Šulc, Petr
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: The self-assembly of colloidal diamond (CD) crystals is considered as one of the most coveted goals of nanotechnology, both from the technological and fundamental points of view. For applications, colloidal diamond is a photonic crystal which can open new possibilities of manipulating light for information processing. From a fundamental point of view, its unique symmetry exacerbates a series of problems that are commonly faced during the self-assembly of target structures, such as the presence of kinetic traps and the formation of crystalline defects and alternative structures (polymorphs). Here we demonstrate that all these problems can be systematically addressed via SAT-assembly, a design framework that converts self-assembly into a satisfiability problem. Contrary to previous solutions (requiring four or more components), we prove that the assembly of the CD crystal only requires a binary mixture. Moreover, we use molecular dynamics simulations of a system composed by nearly a million nucleotides to test a DNA nanotechnology design that constitutes a promising candidate for experimental realization.
description: 12 pages, 4 figures
Counting-Based Effective Dimension and Discrete Regularizations
Creators: name: Horváth, Ivan
name: Markoš, Peter
name: Mendris, Robert
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Fractal-like structures of varying complexity are common in nature, and measure-based dimensions (Minkowski, Hausdorff) supply their basic geometric characterization. However, at the level of fundamental dynamics, which is quantum, structure does not enter via geometry of fixed sets but is encoded in probability distributions on associated spaces. The question then arises whether a robust notion of fractal measure-based dimension exists for structures represented in this way. Starting from effective number theory, we construct all counting-based schemes to select effective supports on collections of objects with probabilities and associate the effective counting dimension (ECD) with each. We then show that ECD is scheme-independent and, thus, a well-defined measure-based dimension with meaning analogous to the Minkowski dimension of fixed sets. In physics language, ECD characterizes probabilistic descriptions arising in a theory or model via discrete ``regularization''. For example, our analysis makes recent surprising results on effective spatial dimensions in quantum chromodynamics and Anderson models well founded. We discuss how to assess the reliability of regularization removals in practice and perform such analysis in the context of 3d Anderson criticality.
description: 5 pages, 1 figure; v2: published version
On the initial value problem for semiclassical gravity without and with quantum state collapses
Creators: name: Juárez-Aubry, Benito A.
name: Kay, Bernard S.
name: Miramontes, Tonatiuh
name: Sudarsky, Daniel
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We explore how the initial value problem may be formulated for globally hyperbolic, Hadamard, solutions of the semiclassical Einstein-Klein-Gordon equations. Given a set of data on an initial 3-surface, consisting of the values on the surface of a spacetime metric and its first 3 time derivatives off the surface, we introduce a notion of 'surface Hadamard' state on the CCR algebra of the surface. We conjecture that, for a given such set of classical Cauchy data with a surface Hadamard state satisfying the semiclassical constraint equations, the initial value problem will be well posed. We present similar conjectures for a semiclassical scalars model and semiclassical electrodynamics. Moreover, partly inspired by work of Parker and Simon in 1993, we define semiclassical gravity `physical solutions' to be those that are (jointly smooth) functions of $\hbar$ and of coordinates continuous in $\hbar$ at $\hbar =0$. We conjecture that for such solutions the second and third time derivatives of the metric off the surface need not be specified, but rather will be determined by that continuity condition. Assuming the initial value conjecture for such physical solutions holds, and that a stochastic rule were available which leads to quantum state collapses occurring on (non-intersecting) random Cauchy surfaces, we discuss the well-posedness of semiclassical gravity with stochastic quantum state collapses. We also discuss two notions of approximate physical semiclassical solutions (both with and without collapses): Namely solutions to order $\hbar$ (first discussed by Parker and Simon in 1993) and solutions to order $\hbar^0$. We point out that the latter do not require higher derivative terms or Hadamard subtractions, but that nevertheless order $\hbar^0$ semiclassical gravity is a distinct theory from classical general relativity capable of incorporating quantum interference phenomena.
description: 47 pages. Corrections implemented, notably Def 11 (preliminary surface Hadamard condition) and certain equations on p. 33. Explanations improved and typos fixed. This version corresponds largely to the published version in JCAP
Demand Response Method Considering Multiple Types of Flexible Loads in Industrial Parks
Creators: name: Cui, Jia
name: Gao, Mingze
name: Zhou, Xiaoming
name: Li, Yang
name: Liu, Wei
name: Tian, Jiazheng
name: Zhang, Ximing
Publisher: name: arXiv
Year: 2022
Subjects: subject: Systems and Control (eess.SY)
subject: Machine Learning (cs.LG)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: With the rapid development of the energy internet, the proportion of flexible loads in smart grid is getting much higher than before. It is highly important to model flexible loads based on demand response. Therefore, a new demand response method considering multiple flexible loads is proposed in this paper to character the integrated demand response (IDR) resources. Firstly, a physical process analytical deduction (PPAD) model is proposed to improve the classification of flexible loads in industrial parks. Scenario generation, data point augmentation, and smooth curves under various operating conditions are considered to enhance the applicability of the model. Secondly, in view of the strong volatility and poor modeling effect of Wasserstein-generative adversarial networks (WGAN), an improved WGAN-gradient penalty (IWGAN-GP) model is developed to get a faster convergence speed than traditional WGAN and generate a higher quality samples. Finally, the PPAD and IWGAN-GP models are jointly implemented to reveal the degree of correlation between flexible loads. Meanwhile, an intelligent offline database is built to deal with the impact of nonlinear factors in different response scenarios. Numerical examples have been performed with the results proving that the proposed method is significantly better than the existing technologies in reducing load modeling deviation and improving the responsiveness of park loads.
description: Submitted to Expert Systems with Applications
Deep Learning-Empowered Semantic Communication Systems with a Shared Knowledge Base
Creators: name: Yi, Peng
name: Cao, Yang
name: Kang, Xin
name: Liang, Ying-Chang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Information Theory (cs.IT)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Deep learning-empowered semantic communication is regarded as a promising candidate for future 6G networks. Although existing semantic communication systems have achieved superior performance compared to traditional methods, the end-to-end architecture adopted by most semantic communication systems is regarded as a black box, leading to the lack of explainability. To tackle this issue, in this paper, a novel semantic communication system with a shared knowledge base is proposed for text transmissions. Specifically, a textual knowledge base constructed by inherently readable sentences is introduced into our system. With the aid of the shared knowledge base, the proposed system integrates the message and corresponding knowledge from the shared knowledge base to obtain the residual information, which enables the system to transmit fewer symbols without semantic performance degradation. In order to make the proposed system more reliable, the semantic self-information and the source entropy are mathematically defined based on the knowledge base. Furthermore, the knowledge base construction algorithm is developed based on a similarity-comparison method, in which a pre-configured threshold can be leveraged to control the size of the knowledge base. Moreover, the simulation results have demonstrated that the proposed approach outperforms existing baseline methods in terms of transmitted data size and sentence similarity.
description: 14 pages, Journal, accepted by IEEE TWC
Resonant tunneling and quantum interference of a two-spin system in silicon tunnel FETs
Creators: name: Moriyama, Satoshi
name: Mori, Takahiro
name: Ono, Keiji
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigated the resonant tunneling of a two-spin system through the double quantum dots in Al-N-implanted silicon tunnel FETs (TFETs) by electrical-transport measurements and Landau-Zener-Stückelberg-Majorana interferometry with and without magnetic fields. Our experimental results revealed the coexistence of spin-conserving and spin-flip tunneling channels in the two-spin system in non-zero magnetic fields. Additionally, we obtained the spin-conserving/spin-flip tunneling rates of the two-spin system through the double quantum dots in the TFET. These findings will improve our understanding of the two-spin system in silicon TFET qubits and may facilitate the coherent control of quantum states through all-electric manipulation.
description: 15 pages, 4 figures
Stacked Autoencoder Based Feature Extraction and Superpixel Generation for Multifrequency PolSAR Image Classification
Creators: name: Gadhiya, Tushar
name: Tangirala, Sumanth
name: Roy, Anil K.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: In this paper we are proposing classification algorithm for multifrequency Polarimetric Synthetic Aperture Radar (PolSAR) image. Using PolSAR decomposition algorithms 33 features are extracted from each frequency band of the given image. Then, a two-layer autoencoder is used to reduce the dimensionality of input feature vector while retaining useful features of the input. This reduced dimensional feature vector is then applied to generate superpixels using simple linear iterative clustering (SLIC) algorithm. Next, a robust feature representation is constructed using both pixel as well as superpixel information. Finally, softmax classifier is used to perform classification task. The advantage of using superpixels is that it preserves spatial information between neighbouring PolSAR pixels and therefore minimises the effect of speckle noise during classification. Experiments have been conducted on Flevoland dataset and the proposed method was found to be superior to other methods available in the literature.
MONETARY POLICY RULES AND ECONOMIC SHOCKS IN THE DSGE MODELS OF SUB-SAHARAN ECONOMIES
Creators: name: Alkader, Ahmed
Publisher: name: Zenodo
Year: 2018

description: The objective of the study is to explain the applicability of the monetary policy rule of the kind

widely used in the standard DSGE models to the DSGE models of SSA economies. It also attempted

to analyze the relative importance of the domestic and external source of economic shocks as well

as the impact of some selected shocks on macroeconomic variables of SSA economies using a

DSGE model. The results are the following: first, in response to the baseline structural shocks, the

monetary aggregate rule better explains SSA economies than the Taylor type interest rate rule. To

put differently, the simple Taylor interest rate rule needs modification to apply it in the DSGE

model of SSA economies. Second, the study shows that both internal and external economic shocks

are responsible for macroeconomic fluctuations in SSA countries, however, the study found that

external economic shocks are importance vis-à-vis the domestic economic shocks
Initialisation of Autonomous Aircraft Visual Inspection Systems via CNN-Based Camera Pose Estimation
Creators: name: Oh, Xueyan
name: Loh, Leonard
name: Foong, Shaohui
name: Koh, Zhong Bao Andy
name: Ng, Kow Leong
name: Tan, Poh Kang
name: Toh, Pei Lin Pearlin
name: Tan, U-Xuan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: General Visual Inspection is a manual inspection process regularly used to detect and localise obvious damage on the exterior of commercial aircraft. There has been increasing demand to perform this process at the boarding gate to minimize the downtime of the aircraft and automating this process is desired to reduce the reliance on human labour. This automation typically requires the first step of estimating a camera's pose with respect to the aircraft for initialisation. However, localisation methods often require infrastructure, which can be very challenging when performed in uncontrolled outdoor environments and within the limited turnover time (approximately 2 hours) on an airport tarmac. In addition, access to commercial aircraft can be very restricted, causing development and testing of solutions to be a challenge. Hence, this paper proposes an on-site infrastructure-less initialisation method, by using the same pan-tilt-zoom camera used for the inspection task to estimate its own pose. This is achieved using a Deep Convolutional Neural Network trained with only synthetic images to regress the camera's pose. We apply domain randomisation when generating our dataset for training our network and improve prediction accuracy by introducing a new component to an existing loss function that leverages on known aircraft geometry to relate position and orientation. Experiments are conducted and we have successfully regressed camera poses with a median error of 0.22 m and 0.73 degrees.
description: This paper has been accepted by 2021 IEEE International Conference on Robotics and Automation (ICRA) with DOI: 10.1109/ICRA48506.2021.9561575
The Structure of the Closure of the Rational Functions in $L^{q}$($μ$)$
Creators: name: Qiu, Zhijian
Publisher: name: arXiv
Year: 2013
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 46E30 30H05, 30E10, 46E15, 47B

description: Let $K$ be a compact subset in the complex plane and let $A(K)$ be the uniform closure of the functions continuous on $K$ and analytic on $K^{\circ}$. Let $μ$ be a positive finite measure with its support contained in $K$. For $1 \leq q < \infty$, let $A^{q}(K,μ)$ denote the closure of $A(K)$ in $L^{q}(μ)$. The aim of this work is to study the structure of the space $A^{q}(K,μ)$. We seek a necessary and sufficient condition on $K$ so that a Thomson-type structure theorem for $A^{q}(K,μ)$ can be established. Our results essentially give perfect solutions to the major open problem in the research filed of theory of subnormal operators and aproximation by analytic functions in the mean .
Macroscopic limits of non-local kinetic descriptions of vehicular traffic
Creators: name: Chiarello, Felisia Angela
name: Tosin, Andrea
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences
subject: 35Q20, 35Q70, 90B20

description: We study the derivation of macroscopic traffic models out of optimal speed and follow-the-leader particle dynamics as hydrodynamic limits of non-local Povzner-type kinetic equations. As a first step, we show that optimal speed vehicle dynamics produce a first order macroscopic model with non-local flux. Next, we show that non-local follow-the-leader vehicle dynamics have a universal macroscopic counterpart in the second order Aw-Rascle-Zhang traffic model, at least when the non-locality of the interactions is sufficiently small. Finally, we show that the same qualitative result holds also for a general class of follow-the-leader dynamics based on the headway of the vehicles rather than on their speed. We also investigate the correspondence between the solutions to particle models and their macroscopic limits by means of numerical simulations.
description: 24 pages, 11 figures
3-regular matchstick graphs with given girth
Creators: name: Kurz, Sascha
name: Mazzuoccolo, Giuseppe
Publisher: name: arXiv
Year: 2014
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C10

description: We consider 3-regular planar matchstick graphs, i.e. those which have a planar embedding such that all edge lengths are equal, with given girth g. For girth 3 it is known that such graphs exist if and only if the number of vertices n is an even integer larger or equal to 8. Here we prove that such graphs exist for girth g=4 if and only if n is even and at least 20. We provide an example for girth g=5 consisting of 180 vertices.
description: 18 pages, 1 table, 8 figures
Monocular UAV Localisation with Deep Learning and Uncertainty Propagation
Creators: name: Oh, Xueyan
name: Lim, Ryan
name: Loh, Leonard
name: Tan, Chee How
name: Foong, Shaohui
name: Tan, U-Xuan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: In this paper, we propose a ground-based monocular UAV localisation system that detects and localises an LED marker attached to the underside of a UAV. Our system removes the need for extensive infrastructure and calibration unlike existing technologies such as UWB, radio frequency and multi-camera systems often used for localisation in GPS-denied environment. To improve deployablity for real-world applications without the need to collect extensive real dataset, we train a CNN on synthetic binary images as opposed to using real images in existing monocular UAV localisation methods, and factor in the camera's zoom to allow tracking of UAVs flying at further distances. We propose NoisyCutout algorithm for augmenting synthetic binary images to simulate binary images processed from real images and show that it improves localisation accuracy as compared to using existing salt-and-pepper and Cutout augmentation methods. We also leverage uncertainty propagation to modify the CNN's loss function and show that this also improves localisation accuracy. Real-world experiments are conducted to evaluate our methods and we achieve an overall 3D RMSE of approximately 0.41m.
description: This paper has been accepted by IEEE Robotics and Automation Letters (Volume: 7, Issue: 3, July 2022) with DOI: https://doi.org/10.1109/LRA.2022.3186750
Neonatal EEG graded for severity of background abnormalities in hypoxic-ischaemic encephalopathy
Creators: name: O'Toole, John M
name: Mathieson, Sean R
name: Raurale, Sumit A
name: Magarelli, Fabio
name: Marnane, William P
name: Lightbody, Gordon
name: Boylan, Geraldine B
Publisher: name: arXiv
Year: 2022
Subjects: subject: Medical Physics (physics.med-ph)
subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This report describes a set of neonatal electroencephalogram (EEG) recordings graded according to the severity of abnormalities in the background pattern. The dataset consists of 169 hours of multichannel EEG from 53 neonates recorded in a neonatal intensive care unit. All neonates received a diagnosis of hypoxic-ischaemic encephalopathy (HIE), the most common cause of brain injury in full term infants. For each neonate, multiple 1-hour epochs of good quality EEG were selected and then graded for background abnormalities. The grading system assesses EEG attributes such as amplitude and frequency, continuity, sleep--wake cycling, symmetry and synchrony, and abnormal waveforms. Background severity was then categorised into 4 grades: normal or mildly abnormal EEG, moderately abnormal EEG, severely abnormal EEG, and inactive EEG. The data can be used as a reference set of multi-channel EEG for neonates with HIE, for EEG training purposes, or for developing and evaluating automated grading algorithms.
Lattice Boltzmann modeling of cholesteric liquid crystal droplets under an oscillatory electric field
Creators: name: Fadda, F.
name: Lamura, A.
name: Tiribocchi, A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Computational Physics (physics.comp-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We numerically study the dynamics of quasi-two dimensional cholesteric liquid crystal droplets in the presence of a time-dependent electric field, rotating at constant angular velocity. A surfactant sitting at droplet interface is also introduced to prevent droplet coalescence. The dynamics is modeled following a hybrid numerical approach, where a standard lattice Boltzmann technique solves the Navier-Stokes equation and a finite difference scheme integrates the evolution equations of liquid crystal and surfactant. Our results show that, once the field is turned on, the liquid crystal rotates coherently triggering a concurrent orbital motion of both droplets around each other, an effect due to the momentum transfer to the surrounding fluid. In addition the topological defects, resulting from the conflict orientation of the liquid crystal within the drops, exhibit a chaotic-like motion in cholesterics with a high pitch, in contrast with a regular one occurring along circular trajectories observed in nematics drops. Such behavior is found to depend on magnitude and frequency of the applied field as well as on the anchoring of the liquid crystal at the droplet interface. These findings are quantitatively evaluated by measuring the angular velocity of fluid and drops for various frequencies of the applied field.
description: 16 pages, 13 figures. Accepted on Communications in Computational Physics
Pseudo-fermions in an electronic loss-gain circuit
Creators: name: Bagarello, Fabio
name: Pantano, Giuseppe
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In some recent papers a loss-gain electronic circuit has been introduced and analyzed within the context of PT-quantum mechanics. In this paper we show that this circuit can be analyzed using the formalism of the so-called pseudo-fermions. In particular we discuss the time behavior of the circuit, and we construct two biorthogonal bases associated to the Liouville matrix $\Lc$ used in the treatment of the dynamics. We relate these bases to $\Lc$ and $\Lc^\dagger$, and we also show that a self-adjoint Liouville-like operator could be introduced in the game. Finally, we describe the time evolution of the circuit in an {\em Heisenberg-like} representation, driven by a non self-adjoint hamiltonian.
description: International Journal of Theoretical Physics, in press