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Physical Sciences, Optics; satellite sensors capturing; spectral- and hyperspectral imaging; atmospheric model; outgoing radiation; atmospheric correction; spectral radiance; surface albedo; spectral brightness factor (coefficient)
Online: 23 October 2018 (17:40:12 CEST)
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Atmospheric correction is a necessary step in image processing data and spectra recorded by spaceborne sensors for pure cloudless atmosphere, primarily in the visible and near-IR spectral range. We have present a fast and sufficiently accurate method of atmospheric correction based on the proposed analytical solutions describing with high accuracy the spectrum of outgoing radiation at the top boundary of the cloudless atmosphere. This technique includes the model of the atmosphere and its optical parameters that are important in terms of radiation transfer. The solution of the inverse problem for finding unknown parameters of the model is carried out by the method of non-linear least squares (Levenberg-Marquardt algorithm) for an individual selected pixel of the image (its spectrum), taking into account the adjacency effects. Using the found parameters of the atmosphere and the average surface albedo, assuming homogeneity of the atmosphere within a certain area of the hyperspectral image (or the whole frame), the spectral albedo at the Earth's surface is calculated for all other pixels. It is essential that the procedure of the numerical simulation with non-linear least squares of the direct transfer problem is based on using analytical solutions, which provides a very short calculation time of the atmospheric parameters (seconds or less) and the ability to perform atmospheric correction "on-fly." Testing methods of atmospheric correction was performed using the synthetic outgoing radiation spectra at the top of the atmosphere (TOA), obtained by numerical simulation in the LibRadTran code, as well as spectra of real space images of the Hyperion hyperspectrometer. A comparison with the results of atmospheric correction in module FLAASH of ENVI package has been performed. Finally, to validate our data obtained by the SHARK method, a comparative analysis with ground-based measurements of Radiometric Calibration Network (RadCalNet) was carried out.
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Physical Sciences, Applied Physics; liquid splashing; dimensional analysis; directed dimensional analysis
Online: 23 October 2018 (09:58:07 CEST)
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This letter attempts to find splashing height of liquid-filled container drop impact to a solid surface by dimensional analysis (DA). Two solutions were obtained by both traditional DA and directed DA without solving any governing equations. It is found that the dircted DA can provide much more useful information than the traditional one. This study shows that the central controlling parameter is called splash number $\mathrm{Sp}=\mathrm{Ga} \mathrm{La}=(\frac{gR^3}{\nu^2})(\frac{\sigma R}{\rho \nu^2})$, which is the collective performance of each quantity. The splash height is given by $ h=H F(\mathrm{Sp})$. From the physics of the splashing number, we can have a fair good picture on the physics of the liquid splashing as follows: the jets propagation will generate vortex streets from the container bottom due to sudden pressure increasing from drop impact (water-hammer effect), which will travel along the container sidewall to the centre of the container and subsequently excite a gravity wave on the liquid surface. The interaction between the gravitational force, surface force and viscous force is responsible for creating droplet splash at the liquid surface.
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Physical Sciences, Astronomy & Astrophysics; galaxy morphology, machine learning; data analysis; object classification
Online: 22 October 2018 (15:01:42 CEST)
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Automated machine classifications of galaxies are necessary because the size of upcoming surveys will overwhelm human volunteers. We improve upon existing machine classification methods by adding the output of SpArcFiRe to the inputs of a machine learning model. We use the human classifications from Galaxy Zoo 1 (GZ1) to train a random forest of decision trees to reproduce the human vote distributions of the Spiral class. We prefer the random forest model over other black box models like neural networks because it allows us to trace post hoc the precise reasoning behind the classification of each galaxy. We find that, across a sample of 470,000 Sloan galaxies that are large enough that details could be seen if they were there, the combination of SpArcFiRe outputs with existing SDSS features provides a better machine classification than either one alone on comparison to Galaxy Zoo 1. We suggest that adding SpArcFiRe outputs as features to any machine learning algorithm will likely improve its performance.
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Physical Sciences, Other; diabetes mellitus; blood glucose; kidney; diabetic neuropathy; pancreas
Online: 22 October 2018 (12:45:08 CEST)
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This present study was designed to find out whether the acankoreagenin showed the antidiabetic and renoprotective effects in streptozotocin (STZ)-induced diabetic nephropathy (DN) rats. Type I diabetes was induced by a single intraperitoneal injection of STZ (70 mg/kg). At the end of the experiment, rats were euthanized and serum/plasma was separated for the determination of glucose, insulin, glycated hemoglobin A1c (HbA1c), C-peptide, biochemical parameters, and kidney function. One kidney was used for determining glutathione, superoxide dismutas, malondialdehyde, and tumor necrosis factor-alpha levels. The other kidney and pancreas were used for histopathological studies and immunohistochemical measurement of transforming growth factor beta (TGF-β) or NF-κB. Acankoreagenin (2 mg/kg) treatments led to a significant reduction in blood glucose assessed via oral glucose tolerance test (OGTT) in diabetic rats at 2 h. The treatment also resulted in improved body weight, decreased HbA1c, restored lipid profile, and renal oxidative stress. By inhibiting NF-κB, the release of proinflammatory cytokines was suppressed and by inhibiting TGF-β, the renal fibrosis was suppressed in STZ-induced diabetic rat model. Histopathological injury was also observed in pancreatic and renal tissues. These findings support the beneficial effect of acankoreagenin treatment in DN, which could be attributed to its antidiabetic and renoprotective effects.
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Physical Sciences, Other; ultra-weak photon emission; age; temporal variation; asymmetry; analytical model; photon diffusion
Online: 19 October 2018 (18:40:31 CEST)
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Ultra-weak photon emissions (UPEs) including those from human have been experimented for decades. The photo-genic origin of UPE has also been attributed to the oxidative stress or free radical production that is unique to metabolically active states of biological organisms. However, there are considerable gaps in quantitative understanding of UPE. In this work, I propose an analytical framework of hypothesis for the initial objective of modeling a few superficial presentations of UPE of human, including the systematic dependency on age, the diurnal variation, and the geometric asymmetry associated with serious asymmetrical pathological conditions. The hypothesis which is currently limited to human assumes a new form of energy state, termed vivo-nergy, which resides only in metabolically active organisms that are also under neuronal control. The hypothesis projects a decrease of the vivo-nergy in human during growth beyond puberty, with the rate of decrease dictated by a critical time-scale---the age of the first opposite-sex sexual intercourse (FOSSI). The hypothesis also proposes a modification of the vivo-nergy by the phases of systematic or homeostatic physiology. The hypothesis further postulates that the deviation of the physiology-modified vivo-nergy from the pre-puberty level is deteriorated by acquired organ-specific pathological conditions. Any reduction of vivo-nergy from the pre-puberty level is hypothesized to proportionally cause oxidative stress that functions as the physical source of UPE. The resulted steady-state diffusion of the photon emitted from a photo-genic source of UPE in a human geometry simplified as a homogeneous spherical domain is modeled by photon diffusion principles incorporating an extrapolated zero-boundary condition. The age and systematic physiology combined determines the intensity of the centered physiological photo-genic source. The acquired (single) pathology sets both the intensity and the off-center position of the (single) pathological photo-genic source. When the age-related, physiology-commanded, and pathology-controlled modifications of the photo-genetic sources are implemented in the photon diffusion model, the photon fluence rate at the surface of the simplified human-representing spherical domain reveals the dependency on age, the temporal variation corresponding to systematic physiology, and the geometric asymmetry associated with significant asymmetric pathological condition as reported previously for UPE. The hypothesis, as it provides analytical conveniences for quantitative estimation of UPE patterns, may be useful to further model-based interpretation of the spatial-temporal characteristics of UPE.
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Lino Miramonti,
M. Agostini,
K. Altenmueller,
S. Appel,
V. Atroshchenko,
Z. Bagdasarian,
D. Basilico,
G. Bellini,
J. Benziger,
D. Bick,
I. Bolognino,
G. Bonfini,
D. Bravo,
B. Caccianiga,
F. Calaprice,
A. Caminata,
S. Caprioli,
M. Carlini,
P. Cavalcante,
F. Cavanna,
A. Chepurnov,
K. Choi,
L. Collica,
S. Davini,
A. Derbin,
X.F. Ding,
A. Di Ludovico,
L. Di Noto,
I. Drachnev,
K. Fomenko,
A. Formozov,
D. Franco,
F. Gabriele,
C. Galbiati,
M. Gschwender,
C. Ghiano,
M. Giammarchi,
A. Goretti,
M. Gromov,
D. Guffanti,
C. Hagner,
T. Houdy,
E. Hungerford,
Aldo Ianni,
Andrea Ianni,
A. Jany,
D. Jeschke,
V. Kobychev,
D. Korablev,
G. Korga,
T. Lachenmaier,
M. Laubenstein,
E. Litvinovich,
F. Lombardi,
P. Lombardi,
L. Ludhova,
G. Lukyanchenko,
L. Lukyanchenko,
I. Machulin,
G. Manuzio,
S. Marcocci,
J. Maricic,
J. Martyn,
E. Meroni,
M. Meyer,
M. Misiaszek,
L. Papp,
O. Penek,
L. Pietrofaccia,
N. Pilipenko,
A. Pocar,
A. Porcelli,
G. Raikov,
G. Ranucci,
A. Razeto,
A. Re,
M. Redchuk,
A. Romani,
N. Rossi,
S. Rottenanger,
S. Schönert,
D. Semenov,
M. Skorokhvatov,
O. Smirnov,
A. Sotnikov,
L.F.F. Stokes,
Y. Suvorov,
R. Tartaglia,
G. Testera,
J. Thurn,
M. Toropova,
E. Unzhakov,
A. Vishneva,
R.B. Vogelaar,
F. von Feilitzsch,
S. Weinz,
M. Wojcik,
M. Wurm,
Z. Yokley,
O. Zaimidoroga,
S. Zavatarelli,
K. Zuber,
G. Zuzel
Physical Sciences, Particle & Field Physics; solar neutrinos; neutrino oscillation; Borexino
Online: 19 October 2018 (13:49:06 CEST)
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Solar neutrinos have played a central role in the discovery of the neutrino oscillation mechanism. They still are proving to be a unique tool to help investigate the fusion reactions that power stars and further probe basic neutrino properties. The Borexino neutrino observatory has been operationally acquiring data at Laboratori Nazionali del Gran Sasso in Italy since 2007. Its main goal is the real-time study of low energy neutrinos (solar or originated elsewhere, such as geo-neutrinos). The latest analysis of experimental data, taken during the so-called Borexino Phase-II (2011-present), will be showcased in this talk - yielding new high-precision, simultaneous wide band flux measurements of the four main solar neutrino components belonging to the "pp" fusion chain (pp, pep, 7Be, 8B), as well as upper limits on the remaining two solar neutrino fluxes (CNO and hep).
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Physical Sciences, Optics; THz spectroscopy; 4-methylimidazole; metamaterial; carcinogen detection
Online: 18 October 2018 (13:58:31 CEST)
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We demonstrate, for the first time, a highly sensitive detection of 4-methylimidazole (4-MeI), a carcinogenic material, by applying an electric field enhancement technique using a terahertz (THz) metamaterial at the THz region. The THz metamaterials were fabricated with a metal array using an electric-field-coupled inductor-capacitor (ELC) resonator structure, and FDTD simulation showed good agreement with experimental results. We measured the THz spectra of the metamaterials to detect 4-MeI concentrations of 0, 1, 2, 5, 10, 15, and 20 mg/L. The resonance frequency of the metamaterial was shifted by approximately 8 GHz and transmittance at the resonance frequency increased to 2 x 10-3 as the concentration was increased, up to 20 mg/L. Our study provides new insight into application of metamaterials to detect carcinogen using a THz technique.
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Physical Sciences, Astronomy & Astrophysics; Gravitational atom; quantum black hole; quantum levels; Schrodinger equation; mass spectrum.
Online: 18 October 2018 (12:39:33 CEST)
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We apply Rosen’s approach to the quantization of the gravitational collapse in the simple case of a pressureless “star of dust” and we find the gravitational potential, the Schroedinger equation and the solution for the collapse’s energy levels without any approximation. By applying the constrains for a black hole (BH), we found the analogous quantum quantities and the BH mass spectrum, again without any approximation. Remarkably, such a mass spectrum is the same which was found by Beken-
stein in 1974. Finally, our approach permits to find the exact quantum representation of the Schwarzschild BH ground state at the Planck scale.
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Physical Sciences, Condensed Matter Physics; molecular dynamics; crystal growth; Avrami coefficients; Pt-Pd alloy
Online: 18 October 2018 (12:02:21 CEST)
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This work aims to investigate the effect of Pt concentration on crystal growth mechanism of Platinum-Palladium (Pt-Pd) binary alloy system during the annealing process starting from amorphous phase until some definite temperatures. The calculations have been performed by using molecular dynamic (MD) simulations. Interatomic interactions are described by on Sutton-Chen type Embedded Atom Potential Energy function. In order to understand the main structural properties at the stable and unstable phases, changes in RDF curves versus time have been analysed for different annealing temperatures. Crystalline type bonded pairs have been determined using MD calculations which is required for the computation of Avrami coefficients and for understanding crystal growth mechanism. The results demonstrate that the increase in concentration of Pt during annealing leads to migration of atoms in the crystal lattice points, elimination of dislocations and formation of perfect crystal structure.
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Physical Sciences, Astronomy & Astrophysics; Planck scale; Mach’s relation; quantum cosmology; critical density; ordinary matter; dark matter; thermal redshift; expansion velocity; Hubble’s law
Online: 18 October 2018 (10:42:57 CEST)
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Considering Planck mass as a baby universe and evolving universe as a growing Planck ball, a hypothetical spherical model of cosmology can be developed. In addition, by considering the famous relation GM = c2R, a Machian model of quantum cosmology can also be developed. Proceeding further, in all directions, cosmic expansion velocity can be referred to ‘from and about’ the baby universe. This hypothetical scenario can be made versatile by adding a heuristic idea: apart from normal expansion, ‘cosmic temperature seems to be redshifted by a factor ; where (Hpl, Ht) represent Planck scale and time dependent Hubble parameters respectively.
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Physical Sciences, Atomic & Molecular Physics; laser induced plasma spectroscopic (LIPS); optical emission spectroscopic (OES); spectroscopy diagnostic; cadmium telluride (CdTe)
Online: 18 October 2018 (06:26:08 CEST)
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In this work, the parameters of plasma (electron temperature (Te), electron density ne, plasma frequency (fp) , Debye length (λD) and Debye number (ND)) have been studied by using the spectrometer that collect the spectrum of Laser produce Cadmium telluride plasma at different energies. The results of electron temperature for CdTe range 0.93-1.18 eV also the electron density 5 × 1010 – 3.8 × 1011 cm-3 have been measured under vacuum reaching 2.5 × 10-2 mbar .Optical properties of CdTe were determined through the optical transmission method using ultraviolet visible spectrophotometer within the range 190 – 1100 nm.
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Physical Sciences, Applied Physics; direct laser writing, multiphoton processing, laser 3D nanolithography, optical 3D printing, microstructures, nanotechnology, mesoscale, two-photon polymerization, microoptics, SZ2080
Online: 17 October 2018 (13:26:32 CEST)
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3D meso-scale structures that can reach up to centimeters in overall size but retain micro- or nano-features, proved to be promising in various science fields ranging from micro-mechanical metamaterials to photonics and bio-medical scaffolds. In this work we present synchronization of the linear and galvano scanners for efficient femtosecond 3D optical printing of objects at the meso-scale (from sub-μm to sub-cm spanning five orders of magnitude). In such configuration the linear stages provide stitch-free structuring at nearly limitless (up to tens-of-cm) working area, while galvo-scanners allow to achieve translation velocities in the range of mm/s-cm/s without sacrificing nano-scale positioning accuracy and preserving undistorted shape of the final print. The principle behind this approach is demonstrated, proving its inherent advantages in comparison to separate use of only linear stages or scanners. The printing rate is calculated in terms voxels/s, showcasing the capability to maintain an optimal feature size while increasing throughput. Full capabilities of this approach are demonstrated by fabricating structures that reach millimeters in size but still retain μm-scale features: scaffolds for cell growth, microlenses and photonic crystals. All this is combined into a benchmark structure: a meso-butterfly. Provided results show that synchronization of two scan modes is crucial for the end goal of industrial-scale implementation of this technology and makes the laser printing well aligned with similar approaches in nanofabrication by electron and ion beams.
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Physical Sciences, Nuclear & High Energy Physics; Strong nuclear gravity, nuclear elementary charge, strong coupling constant, nuclear stability range, binding energy of isotopes, magic proton numbers.
Online: 16 October 2018 (17:28:20 CEST)
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With reference to our earlier published views on large nuclear gravitational constant , nuclear elementary charge and strong coupling constant , in this paper, we present simple relations for nuclear stability range, binding energy of isotopes and magic proton numbers.
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Physical Sciences, Particle & Field Physics; quantum chromodynamics, color confinement, superconformal algebra, conformal symmetry, light-front holography
Online: 16 October 2018 (16:32:58 CEST)
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The QCD Lagrangian is based on quark and gluonic fields -- not squarks nor gluinos. However, one can show that its hadronic eigensolutions conform to a representation of superconformal algebra, reflecting the underlying conformal symmetry of chiral QCD. The eigensolutions of superconformal algebra provide a unified Regge spectroscopy of meson, baryon, and tetraquarks of the same parity and twist as equal-mass members of the same 4-plet representation with a universal Regge slope. The predictions from light-front holography and superconformal algebra can also be extended to mesons, baryons, and tetraquarks with strange, charm and bottom quarks. % The pion $q \bar q$ eigenstate has zero mass for $m_q=0.$ % % A key tool is the remarkable observation of de Alfaro, Fubini, and Furlan (dAFF) which shows how a mass scale can appear in the Hamiltonian and the equations of motion while retaining the conformal symmetry of the action. When one applies the dAFF procedure to chiral QCD, a mass scale $\kappa$ appears which determines universal Regge slopes, hadron masses in the absence of the Higgs coupling. One also predicts the form of the nonperturbative QCD running coupling: $\alpha_s(Q^2) \propto e^{-{Q^2/4 \kappa^2}}$, in agreement with the effective charge determined from measurements of the Bjorken sum rule. One also obtains viable predictions for spacelike and timelike hadronic form factors, structure functions, distribution amplitudes, and transverse momentum distributions. % The combination of conformal symmetry, light-front dynamics, its holographic mapping to AdS$_5$ space, and the dAFF procedure thus provide new insights, not only into the physics underlying color confinement, but also the nonperturbative QCD coupling and the QCD mass scale.
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Physical Sciences, Condensed Matter Physics; graphite; diamagnetism; thickness dependence; susceptibility; interfaces; conductivity; graphene
Online: 16 October 2018 (15:56:35 CEST)
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Recently published structural analysis and galvanomagnetic studies of a large number of different bulk and mesoscopic graphite samples of high quality and purity reveal that the common picture assuming graphite samples as a semimetal with a homogeneous carrier density of conduction electrons is misleading. These new studies indicate that the main electrical conduction path occurs within 2D interfaces embedded in semiconducting Bernal and/or rhombohedral stacking regions. This new knowledge incites us to revise experimentally and theoretically the diamagnetism of graphite samples. We found that the $c$-axis susceptibility of highly pure oriented graphite samples is not really constant but can vary several tens of percent for bulk samples with thickness $t \gtrsim 30~\mu$m, whereas by a much larger factor for samples with smaller thickness. The observed decrease of the susceptibility with sample thickness resembles qualitatively the one reported for the electrical conductivity and indicates that the main part of the $c-$axis diamagnetic signal is not intrinsic of the ideal graphite structure but it is due to the highly conducting 2D interfaces. The interpretation of the main diamagnetic signal of graphite agrees with the reported description of its galvanomagnetic properties and provides a hint to understand some magnetic peculiarities of thin graphite samples.
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Physical Sciences, Mathematical Physics; Born-Jordan, quantization, short time propagator
Online: 16 October 2018 (10:59:09 CEST)
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We have shown in previous work that the equivalence of the Heisenberg and Schrödinger pictures of quantum mechanics requires the use of the Born and Jordan quantization rules. In the present work we give further evidence that the Born--Jordan rule is the correct quantization scheme for quantum mechanics. For this purpose we use correct short-time approximations to the action functional, initially due to Makri and Miller, and show that these lead to the desired quantization of the classical Hamiltonian.
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Physical Sciences, Other; electron paramagnetic resonance; EPR; multi-frequency EPR; high-spin cobalt complex; resolution of A-mid
Online: 16 October 2018 (10:04:16 CEST)
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Low-frequency electron paramagnetic resonance (EPR) is used to extract the EPR parameter A-mid and support the approximate X-band value of g-mid for Ba(CoyZn1/3-yTa2/3)O3. Although cobalt hyperfine structure for the [+/−1/2> state is often unresolved at X-band or S-band, it is resolved in measurements on this compound. This allows for detailed analysis of the molecular orbital for the [+/−1/2> state, which is often the ground state. Moreover, this work shows that the EPR parameters for Co substituted into Zn compounds gives important insight into the properties of zinc binding sites.
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Physical Sciences, Applied Physics; plastic dislocation density tensor
Online: 15 October 2018 (19:32:52 CEST)
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This letter attempts to clarify an issue regarding the proper definition of plastic dislocation density tensor. This study shows that the Ortiz’s and Berdichevsky’s plastic dislocation density tensor are equivalent with each other, but not with Kondo’s one. To fix the problem, we propose a modified version of Kondo’s plastic dislocation density tensor.
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Physical Sciences, General & Theoretical Physics; statistical physics; special relativity; arrow of time
Online: 15 October 2018 (14:54:32 CEST)
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Consistent with special relativity and statistical physics, here we construct a partition function of space-time events. The union of these two theories resolves longstanding problems in regards to time. It augments the standard description of time given by the (non-relativistic) arrow of time to one able to show the emergence of three macroscopic regimes of time: the past, the present, and the future, represented by space-like entropy, light-like entropy, and time-like entropy, respectively, and in a manner consistent with our experience of said regimes. First, using Fermi-Dirac statistics, we find that the system essentially describes a "waterfall" of space-time events. This "waterfall" recedes in space-time at the speed of light towards the direction of the future as it "floods" local space with events that it depletes from the past. In this union, an observer O will perceive two horizons that can be interpreted as hiding events behind it. The first is an event horizon, and its entropy hides events in the regions that O cannot see. The second is a time horizon, and its entropy "shields" events from O's causal influence. As only past events are "shielded", and not future events, an asymmetry in time is thus created. Finally, future events are hidden by an entropy prohibiting O from knowing the future before the present catches on.
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Physical Sciences, Nuclear & High Energy Physics; JUNO; liquid scintillator; neutrino mass hierarchy.
Online: 12 October 2018 (18:38:11 CEST)
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The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kton liquid scintillator multi-purpose underground detector, under construction near the chinese city of Jiangmen, with data taking expected to start in 2021. The main goal of the experiment is the neutrino mass hierarchy determination, with more than three sigma significance, and the high precision neutrino oscillation parameters measurements, detecting electron anti-neutrinos, emitted from two near-by (baseline of about 53 km) nuclear power plants. Besides, the unprecedented liquid scintillator type detector performance in target mass, energy resolution, energy calibration precision and low-energy threshold, features a rich physics program for the detection of low-energy astrophysical neutrinos, such as galactic core-collapse supernova neutrinos, solar neutrinos and geo-neutrinos.
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Igor Bychkov,
Andrey Demichev,
Julia Dubenskaya,
Oleg Fedorov,
Andreas Haungs,
Andreas Heiss,
Yulia Kazarina,
Elena Korosteleva,
Dmitriy Kostunin,
Alexander Kryukov,
Andrey Mikhailov,
Minh-Duc Nguyen,
Stanislav Polyakov,
Evgeny Postnikov,
Alexey Shigarov,
Dmitry Shipilov,
Achim Streit,
Viktoria Tokareva,
Doris Wochele,
Jürgen Wochele,
Dmitry Zhurov
Physical Sciences, Astronomy & Astrophysics; astroparticle physics, cosmic rays, data life cycle management, data curation, meta data, big data, deep learning, open data
Online: 12 October 2018 (16:48:32 CEST)
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Modern experimental astroparticle physics features large-scale setups measuring different messengers, namely high-energy particles generated by cosmic accelerators (e.g. supernova remnants, active galactic nuclei, etc): cosmic and gamma rays, neutrinos and recently discovered gravitational waves. Ongoing and future experiments are distributed over the Earth including ground, underground/underwater setups as well as balloon payloads and spacecrafts. The data acquired by these experiments have different formats, storage concepts and publication policies. Such differences are a crucial issue in the era of big data and of multi-messenger analysis strategies in astroparticle physics. We propose a service ASTROPARTICLE.ONLINE in the frame of which we develop an open science system which enables to publish, store, search, select and analyse astroparticle physics data. The cosmic-ray experiments KASCADE-Grande and TAIGA were chosen as pilot experiments to be included in this framework. In the first step of our initiative we will develop and test the following components of the full data life cycle concept: (i) describing, storing and reusing of astroparticle data; (ii) software for performing multi-experiment and multi-messenger analyses like deep-learning methods; (iii) outreach including example applications and tutorial for students and scientists outside the specific research field. In the present paper we describe the concepts of our initiative, and in particular the plans toward a common, federated astroparticle data storage.
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Physical Sciences, Optics; PPT symmetry; SL(2, C); hyperbolic geometry
Online: 12 October 2018 (14:42:28 CEST)
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We reelaborate on the basic properties of PT symmetry from a geometrical Perspective. The transfer matrix associated with these systems induces a Möbius transformation in the complex plane. The trace of this matrix classifies the actions into three types that represent rotations, translations, and parallel displacements. We find that a PT invariant system can be pictured as a complex conjugation followed by an inversion in a circle. We elucidate the physical meaning of these geometrical operations and link them with measurable properties of the system.
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Physical Sciences, Nuclear & High Energy Physics; wind speed; wind power; scale factor and shape factor
Online: 12 October 2018 (07:13:33 CEST)
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The research sought to investigate the long term characteristics of wind in the Kisii region (elevation 1710m above sea level, 0.68oS, 34.79o E). Wind speeds were analyzed and characterized on short term (per month for a year) and then simulated for long term (ten years) measured hourly series data of daily wind speeds at a height of 10m. The analysis included daily wind data which was grouped into discrete data and then calculated to represent; the mean wind speed, diurnal variations, daily variations as well as the monthly variations. The wind speed frequency distribution at the height 10 m was found to be 2.9ms-1 with a standard deviation of 1.5. Based on the two month’s data that was extracted from the AcuRite 01024 Wireless Weather Stations with 5-in-1 Weather Sensor experiments set at three sites in the region, averages of wind speeds at hub heights of 10m and 13m were calculated and found to be 1.7m/s, 2.0m/s for Ikobe station, 2.4m/s, 2.8m/s for Kisii University stations, and 1.3m/s, 1.6m/s for Nyamecheo station respectively. Then extrapolation was done to determine average wind speeds at heights (20m, 30m, 50m, and 70m) which were found to be 85.55W/m2, 181.75W/m2, 470.4W/m2 and 879.9W/m2 respectively. The wind speed data was used statistically to model a Weibull probability density function and used to determine the power density for Kisii region.
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Physical Sciences, Condensed Matter Physics; agnetocaloric effect; quantum dot; Aharonov-Bohm
Online: 11 October 2018 (07:53:07 CEST)
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In this work, we report the magnetocaloric effect (MCE) in a quantum dot corresponding to an electron interacting with an antidot, under the effect of an Aharonov-Bohm flux subjected to a parabolic confinement potential. We use the Bogachek and Landman model, which additionally allows the study of quantum dots with Fock-Darwin energy levels for vanishing antidot radius and flux. We find that the Aharonov-Bohm flux (AB-flux) strongly controls the oscillatory behaviour of the MCE, thus acting as a control parameter for the cooling or heating of the magnetocaloric effect. We propose a way to detect AB-flux by measuring temperature differences.
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Physical Sciences, Other; thermodynamics; entropy; artificial intelligence; differential geometry; computational physics
Online: 10 October 2018 (07:19:04 CEST)
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Because only two variables are needed to characterize a simple thermodynamic system in equilibrium, any such system is constrained on a 2D manifold. Of particular interest are the exact 1-forms on the cotangent space of that manifold, since the integral of exact 1-forms is path-independent, a crucial property satisfied by state variables such as internal energy dE and entropy dS. Our prior work [1] shows that given an appropriate language of vector calculus, a machine can re-discover the Maxwell equations and the incompressible Navier-Stokes equations from data. In this paper, We enhance this language by including differential forms and show that machines can re-discover the equation for entropy dS given data. Since entropy appears in various fields of science in different guises, a potential extension of this work is to use the machinery developed in this paper to let machines discover the expressions for entropy from data in fields other than classical thermodynamics.
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Physical Sciences, Condensed Matter Physics; granular materials; displacement fluctuations; $q$-gaussian; strain localization
Online: 9 October 2018 (07:13:57 CEST)
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The statistics of grain displacements probability distribution function (pdf) during the shear of a granular medium displays an unusual dependence with the shear increment upscaling as recently evinced [Phys. Rev. Lett. 115 238301 2015]. Basically, the pdf of grain displacements has clear nonextensive ($q$-Gaussian) features at small scales but approaches to Gaussian characteristics at large shear window scales -- the granulence effect. Here, we extend this analysis studying a larger system (more grains considered in the experimental setup) which exhibits a severe shear band fault during the macroscopic straining. We calculate the pdf of grain displacements and the dependency of the $q$-statistics with the shear increment. This analysis have shown a singular behavior of $q$ at large scales, displaying a non-monotonic dependence with the shear increment. By means of an independent image analysis, we demonstrate that this singular non-monotonicity could be associated with the emergence of a shear band within the confined system. We show that the exact point where the $q$-value inverts its tendency coincides with the emergence of a giant percolation cluster along the system, caused by the shear band. We believe that this original approach using Statistical Mechanics tools to identify shear bands can be a very useful piece to solve the complex puzzle of the rheology of dense granular systems.
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Physical Sciences, Other; Cosmic-rays; Citizien Science; Extensive air showers
Online: 8 October 2018 (17:45:43 CEST)
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The Cosmic-Ray Extremely Distributed Observatory (CREDO) is a project dedicated to global studies of extremely extended cosmic-ray phenomena, the cosmic-ray ensembles (CRE), beyond the capabilities of existing detectors and observatories. Up to date cosmic-ray research has been focused on detecting single air showers, while the search for ensembles of cosmic-rays, which may overspread a significant fraction of the Earth, is a scientific terra incognita. Instead of developing and commissioning a completely new global detector infrastructure, CREDO proposes approaching the global cosmic-ray analysis objectives with all types of available detectors, from professional to pocket size, merged into a worldwide network. With such a network it is possible to search for evidences of correlated cosmic-ray ensembles. One of the observables that can be investigated in CREDO is a number of spatially isolated events collected in a small time window which could shed light on fundamental physics issues. The CREDO mission and strategy requires active engagement of a large number of participants, also non-experts, who will contribute to the project by using common electronic devices (e.g. smartphones). In this note the status and perspectives of the project is presented.
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Physical Sciences, Particle & Field Physics; particle physics; unification of forces; self-organization; coupling constants; quark flavors; quark mixing amplitudes; quantum statistics; open systems; Feigenbaum universality; synchronization
Online: 8 October 2018 (16:29:00 CEST)
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A number of experiments suggest that the elementary particles are non-local entities. A dissipative self-organization, that treats particles as open systems may provide a better understanding of the underlying phenomena than conservative models. The proposed toy model is such an attempt. We found that self-gravitation (although accompanied by self-diffusion) may not only be compatible with the quantum phenomena but is perhaps the major reason for the existence of quantum fields. According to the proposed model, fields/particles (resemble those of the Standard Model) emerge from a dynamic self-organized medium (which we associate with vacuum dust) from competition between self-gravitation and self-diffusion. These forces produce turbulence in the form of vortices (which we call vacuum cells) that serve as the building blocks for fields and particles. Field/particle features and symmetries are based on their internal (intracellular) dynamics and vortex synchronization (intercellular dynamics). This model allows for rough estimations of relative field coupling strengths, the quantity of charges and flavors, the probabilities of quark transmutations, the dimensionality and the topologies of phase spaces, and other Standard Model parameters that came not from the theory but rather determined by experiment.
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Physical Sciences, Condensed Matter Physics; interfacial rheology; interfacial shear rheometer; bicone interfacial rheometer; flow field based data processing
Online: 8 October 2018 (13:15:25 CEST)
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Flow field based methods are becoming increasingly popular for the analysis of interfacial shear rheology data. Such methods take properly into account the subphase drag by solving the Navier-Stokes equations for the bulk phases flows, together with the Boussinesq-Scriven boundary condition at the fluid-fluid interface, and the probe equation of motion. Such methods have been successfully implemented at the double wall-ring (DWR), the magnetic rod (MR), and the bicone interfacial shear rheometers. However, a study of the errors introduced directly by the numerical processing is still lacking. Here we report on a study of the errors introduced exclusively by the numerical procedure corresponding to the bicone geometry at an air-water interface. In our study we directly input a preset the value of the complex interfacial viscosity and we numerically obtain the corresponding flow field and the complex amplitude ratio for the probe motion. Then we use the standard iterative procedure to obtain the calculated complex viscosity value. A detailed comparison of the set and calculated complex viscosity values is made upon changing different parameters such as real and imaginary parts of the complex interfacial viscosity and frequency. The observed discrepancies yield a detailed landscape of the numerically introduced errors.
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Pinggui Wang,
Xiuhua Fu,
Des Gibson,
Lewis Fleming,
Cheng Li,
Manu Muhiyudin,
Shigeng Song,
David Hutson,
David Moodie,
Calum MacGregor,
Matthew Steer
Physical Sciences, Optics; NDIR; methane; sensor; infrared; thin film; III-V; heterostructure; bandpass; microwave; sputter; MBE
Online: 7 October 2018 (12:52:34 CEST)
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In this work performance improvements are described of a low power consumption non-dispersive infrared (NDIR) methane (CH4) gas sensor using customised optical thin film bandpass filters (BPF). BPF’s shape the spectral characteristic of the combined mid infrared III-V based light emitting diode (LED)/ photodiode (PD) light source/detector optopair, enhancing NDIR CH4 sensor performance. The BPF, deposited using a novel microwave plasma assisted pulsed DC sputter deposition process, is deposited at room temperature directly onto the temperature sensitive PD heterostructure. BPF’s comprise germanium (Ge) and niobium pentoxide (Nb2O5) alternating high and low refractive index layers respectively. Two different optical filter designs are progressed; with BPF bandwidths (BWs) of 160 nm and 300 nm. Comparison of modelled and measured NDIR sensor performance is described, highlighting maximized signal to noise ratio (SNR) and minimized cross talk performance benefits. BPF spectral stability for various environmental temperature and humidity conditions is demonstrated.
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Rongbo Wu,
Min Wang,
Jian Xu,
Jia Qi,
Wei Chu,
Zhiwei Fang,
Jianhao Zhang,
Junxia Zhou,
Lingling Qiao,
Zhifang Chai,
Jintian Lin,
Ya Cheng
Physical Sciences, Optics; lithium niobate; waveguide; photonic integrated circuit; propagation loss; optical lithography; chemo-mechanical polishing
Online: 7 October 2018 (12:34:27 CEST)
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We develop a technique for realizing lithium niobate on insulator (LNOI) waveguides of a multi-centimeter-length with a propagation loss as low as 0.027 dB/cm. Our technique relies on patterning a chromium (Cr) thin film coated on the top surface of LNOI into a hard mask with a femtosecond laser followed by the chemo-mechanical polishing for structuring the LNOI into the waveguides. The surface roughness on the waveguides is determined to be 0.452 nm with an atomic force microscope (AFM). The approach is compatible with other surface patterning technologies such as optical and electron beam lithographies or laser direct writing, enabling high-throughput manufacturing of large-scale LNOI-based photonic integrated circuits.
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Physical Sciences, Astronomy & Astrophysics; radio astronomy; interferometry; square kilometre array; big data; faraday tomography
Online: 7 October 2018 (10:13:42 CEST)
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The Square Kilometre Array (SKA) will be both the largest radio telescope ever constructed and the largest Big Data project in the known Universe. The first phase of the project will generate on the order of 5 zettabytes of data per year. A critical task for the SKA will be its ability to process data for science, which will need to be conducted by science pipelines. Together with polarization data from the LOFAR Multifrequency Snapshot Sky Survey (MSSS), we have been developing a realistic SKA-like science pipeline that can handle the large data volumes generated by LOFAR at 150 MHz. The pipeline uses task-based parallelism to image, detect sources, and perform Faraday Tomography across the entire LOFAR sky. The project thereby provides a unique opportunity to contribute to the technological development of the SKA telescope, while simultaneously enabling cutting-edge scientific results. In this paper, we provide an update on current efforts to develop a science pipeline that can enable tight constraints on the magnetised large-scale structure of the Universe.
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Physical Sciences, Mathematical Physics; Bioconvection, Magnetohydrodynamics, Scaling group of transformations, Slip boundary conditions, Chemical reaction
Online: 5 October 2018 (13:39:39 CEST)
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Bioconvective flows have attracted attention in recent years due to actual and potential applications. In this paper, we consider a steady and laminar convective MHD flow of a nanofluid with heat, mass and microorganism transfer with a heat source/sink present. In addition, we assume there exists a first order chemical reaction. The governing partial differential equations (PDEs) are reduced to ordinary differential equations (ODEs) using the scaling group transformation and the associated boundary value problem is then solved. The influences of selected governing parameters on the dimensionless velocity, temperature, nanoparticle concentration, density of motile microorganisms, skin friction, heat transfer, mass transfer, and motile microorganism density rates are computed and discussed
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Physical Sciences, Applied Physics; 2D materials, field effect transistors, PMMA, tungsten diselenide
Online: 5 October 2018 (11:55:00 CEST)
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We study the effect of polymer coating, pressure, temperature and light on the electrical characteristics of monolayer WSe2 back-gated transistors with quasi-ohmic Ni/Au contacts. We prove that the removal of a layer of poly(methyl methacrylate) or a decrease of the pressure change the device conductivity from p to n-type. We demonstrate a gate-tunable Schottky barrier at the contacts and measure a barrier height of ~70 meV in flat-band condition. We report and discuss a temperature-driven change in the mobility and the subthreshold slope which we use to estimate the trap density at the WSe2/SiO2 interface. We study the spectral photoresponse of the device, that can be used as a photodetector with a responsivity of ~0.5 AW-1 at 700 nm wavelength and 0.37 mW/cm2 optical power.
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Physical Sciences, Astronomy & Astrophysics; galactic magnetic field; RM-synthesis; Faraday depolarization; wavelet analysis
Online: 4 October 2018 (17:27:30 CEST)
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We present an idea how to use long-wavelength multi-wavelength radio continuum observations of spiral galaxies to isolate magnetic structures which were previously accessible from short-wavelength observations only. The approach is based on the RM-synthesis and 2D continuous wavelet transform. Wavelet analysis helps to recognize a configuration of small-scale structures which are produced by Faraday dispersion. We find that these structures can trace galactic magnetic arms for the case of the galaxy NGC 6946 observed at $\lambda = 17 \div 22$~cm. We support this interpretation by an analysis of a synthetic observation obtained using a realistic model of a galactic magnetic field.
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Physical Sciences, Fluids & Plasmas; Turbulence, mean velocity, uctuation velocity, the Reynolds stress tensor, vorticity, turbulence closure problem
Online: 4 October 2018 (16:43:09 CEST)
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This paper proposed an explicit and simple representation of velocity fluctuation and the Reynolds stress tensor in terms of the mean velocity field. The proposed turbulence equations are closed. The proposed formulations reveal that the mean vorticity is the key source of producing turbulence. It is found that there are no velocity fluctuation and turbulence if there were no vorticity. As a natural consequence, the laminar- turbulence transition condition was obtained in a rational way.
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Physical Sciences, Fluids & Plasmas; Plasma Generation Techniques, Applications of Plasma; Fusion technology; Plasma ion implantation and Deposition.
Online: 3 October 2018 (17:54:34 CEST)
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Plasma being the fourth and most abundant form of matter extensively exists in the universe in the inter-galactic regions. It provides an electrically neutral medium of unbound negative and positive charged particles, which has been produced by subjecting air and various other gaseous mixtures to strengthen the electromagnetic field and by heating compressed air or inert gasses for creating negative and positive charged particles known as ions. Nowadays, many researchers are paying attention to the formation of artificial Plasma and its potential benefits for mankind. The literature is sparsely populated with the applications of Plasma. This paper presents specific methods of generation and applications of Plasma, which benefits humankind in various fields, such as in electrical, mechanical, chemical and medical fields. These applications include hydrogen production from alcohol, copper bonding, semiconductor processing, surface treatment, Plasma polymerization, coating, Plasma display panels, antenna beam forming, nanotechnology, Plasma Torch, Plasma pencils, low-current non-thermal Plasmatron, treatment of prostate cancer, Plasma source ion implantation, cutting by Plasma, Plasma etching, pollution control, neutralization of liquid radioactive waste, etc. Resultantly, worth of Plasma technology in the medical industry is increasing exponentially that is closing the gap between its benefits and cost of equipment used for generating and controlling it.
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Physical Sciences, Astronomy & Astrophysics; Gravitation - Fundamental Problems and General Formalism; Electrodynamics; Scale Invariance; Mach Principle; Dark Energy
Online: 3 October 2018 (17:35:51 CEST)
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As gravitation and electromagnetism are closely analogous long-range interactions, and gravitation is
formulated in terms of geometry in general relativity (GR), we expect the latter also to appear through the geometry. This unification has however remained an unfulfilled goal. The goal is achieved here in a new theory, which results from the principles of equivalence and Mach supplemented with a novel insight that the field tensors in a geometric theory of gravitation and electromagnetism must be traceless, since these long-range interactions are mediated by virtual exchange of massless particles whose mass is expected to be related to the trace of the field tensors. Hence the Riemann tensor, like the analogous electromagnetic field tensor, must be traceless. Thence emerges a scale- invariant, Machian theory of gravitation and electrodynamics unified, wherein the vanishing of the Ricci tensor appears as a boundary condition. While the field equations of the theory are given by the vanishing divergence of the respective field tensors and their duals, the matter and charge emerge from the spacetime. A quantitative formulation of the emergent fields embodied in ‘energymomentum super tensors’ follows from the respective Bianchi identities for the two fields. The resulting theory is valid at all scales and explains the observations without invoking the non-baryonic dark matter, dark energy or inflation. Moreover, it answers the questions that the GR-based standard paradigm could not address.
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Physical Sciences, General & Theoretical Physics; calorons, thermal ground state, wave-particle duality, cosmological model, local-global discrepancy in H0
Online: 2 October 2018 (18:17:40 CEST)
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In the first part of this talk we review some prerequisites for and essential arguments involved in the construction of the thermal-ground-state estimate for the deconfining phase in the thermodynamics of SU(2) Quantum Yang-Mills theory and how this structure supports its distinct excitations. The second part applies deconfining SU(2) Yang-Mills thermodynamics to the Cosmic Microwave Background in view of (i) a modified temperature-redshift relation with an interesting link to correlation-length criticality in the 3D Ising model, (ii) the implied minimal changes in the dark sector of the cosmological model, and (iii) best-fit parameter values of this model when confronted with the spectra of the angular two-point functions TT, TE, and EE, excluding the low-$l$ physics. The latter, which is treated in an incomplete way because of the omission of radiative effects, is addressed in passing towards future work.
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Physical Sciences, Condensed Matter Physics; entanglement entropy; quantum phase transition; finite size scaling; periodically driven model; quantum Ising chain
Online: 30 September 2018 (10:00:52 CEST)
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The out-of-equilibrium dynamics of many body systems has recently received a burst of interest, also due to experimental implementations. The dynamics of both observables, such as magnetization and susceptibilities, and quantum information related quantities, such as concurrence and entanglement entropy, have been investigated under different protocols bringing the system out of equilibrium. In this paper we focus on the entanglement entropy dynamics under a sinusoidal drive of the tranverse magnetic field in the 1D quantum Ising model. We find that the area and the volume law of the entanglement entropy coexist under periodic drive for an initial non-critical ground state. Furthermore, starting from a critical ground state, the entanglement entropy exhibits finite size scaling even under such a periodic drive. This critical-like behaviour of the out-of-equilibrium driven state can persist for arbitrarily long time, provided that the entanglement entropy is evaluated on increasingly subsytem sizes, whereas for smaller sizes a volume law holds. Finally, we give an interpretation of the simultaneous occurrence of critical and non-critical behaviour in terms of the propagation of Floquet quasi-particles.
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Physical Sciences, Applied Physics; silicon; near-infrared; photodetectors, internal photoemission; erbium.
Online: 28 September 2018 (18:14:09 CEST)
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This paper presents the design, fabrication and characterization of Schottky erbium/silicon photodetectors working at 1.55 µm. These erbium/silicon junctions are carefully characterized using both electric and optical measurements at room temperature. A Schottky barrier ΦB of ~673 meV is extrapolated; the photodetectors show external responsivity of 0.55 mA/W at room temperature under a 8 V of reverse bias applied. In addition, the device performance is discussed in terms of normalized noise and noise equivalent power. To the best of our knowledge, these are the first Er/Si photodetectors designed for operation in free space at 1.55 µm. The proposed devices will pave the way towards development of Er-based photodetectors and light sources to be monolithically integrated in the same silicon substrate and both operating at 1.55 µm.
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Physical Sciences, Optics; high-order harmonic generation; 3D non-adiabatic model; simulation; artificial neural network; prediction
Online: 28 September 2018 (13:02:36 CEST)
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In this work we present the results obtained with an artificial neural network (ANN) which we trained to predict the expected output of high-order harmonic generation (HHG) process, while exploring a multi-dimensional parameter space. We argue on the utility and efficiency of the ANN model and demonstrate its ability to predict the outcome of HHG simulations. In this case study we present the results for a loose focusing HHG beamline, where the changing parameters are: the laser pulse energy, gas pressure, gas cell position relative to focus and gas cell length. The physical quantity which we predict here using ANN is directly related to the total harmonic yield in a specified spectral domain (20-40 eV). We discuss the versatility and adaptability of the presented method.
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Physical Sciences, Atomic & Molecular Physics; Schrödinger equation; vibrational spectrum; collocation; inverse multiquadratic function; rectangular matrix
Online: 28 September 2018 (12:15:42 CEST)
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We explore the use of inverse multiquadratic (IMQ) functions as basis functions when solving the vibrational Schrödinger equation with the rectangular collocation method. The quality of the vibrational spectrum of formaldehyde (in six dimensions) is compared to that obtained using Gaussian basis functions when using different numbers of width-optimized IMQ functions. The effects of the ratio of the number of collocation points to the number of basis functions and of the choice of the IMQ exponent are studied. We show that the IMQ basis can be used with parameters where the IMQ function is not integrable. We find that the quality of the spectrum with IMQ basis functions is somewhat lower that that with a Gaussian basis when the basis size is large and for a range of IMQ exponents. The IMQ functions are, however, advantageous when a small number of functions is used or with a small number of collocation points e.g. when using square collocation.
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Physical Sciences, General & Theoretical Physics; state of matter, quantum entanglement, Bohmian mechanics
Online: 25 September 2018 (13:59:31 CEST)
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It is shown that quantum entanglement is the only force able to maintain the fourth state of matter, possessing fixed shape at an arbitrary volume. Accordingly, a new relativistic Schrödinger equation is derived and transformed further to the relativistic Bohmian mechanics via the Madelung transformation. Three dissipative models are proposed as extensions of the quantum relativistic Hamilton-Jacobi equation. The corresponding dispersion relations are obtained.
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Physical Sciences, Astronomy & Astrophysics; hypothesis; collision; heavy elements; solar system
Online: 25 September 2018 (10:47:51 CEST)
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Why is it that in the neighborhood of a calm ordinary star (the Sun) located at the quiet periphery of its galaxy (the Milky Way), non-native heavy elements are abundant in such concentrated form? Where did these elements really come from? Where did Earth's gold come from? Our analysis of the known data offers a fact-reconciling hypothesis: What if, in the early solar system, an explosive collision occurred -- of a traveling from afar giant-nuclear-drop-like object with a local massive dense object (perhaps a then-existent companion of the Sun) -- and the debris, through the multitude of reaction channels and nuclei transformations, was then responsible for (1) the enrichment of the solar system with the cocktail of all detected exogenous chemical elements, and (2) the eventual formation of the terrestrial planets that pre-collision did not exist, thus offering a possible explanation for their inner position and compositional differences within the predominantly hydrogen-helium rest of the solar system.
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Physical Sciences, General & Theoretical Physics; Raychaudhuri equation; atoms of spacetime
Online: 24 September 2018 (19:09:46 CEST)
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The effects on Raychaudhuri's equation of an intrinsically discrete or particle nature of spacetime are investigated, through consideration of null congruences emerging from, or converging to, a generic point of spacetime, i.e. in geometric circumstances somehow prototypical of singularity issues. This is done from an effective point of view, meaning through a (continuous) description of spacetime modified to embody the existence of an intrinsic discreteness on the small scale, adding to previous results for non-null congruences. Various expressions for the effective rate of change of expansion are derived. They in particular provide finite values for the limiting effective expansion and its rate of variation when approaching the focal point; this on top of resulting non vanishing the limiting cross-sectional area itself of the congruence.
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Physical Sciences, Fluids & Plasmas; Turbulence, the Reynolds stress tensor, turbulence closure problem
Online: 24 September 2018 (15:03:40 CEST)
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This paper attempts to clarify an issue regarding the lasting unsolved problem of turbulence, namely the closure problem. This study shows that all perspectives regarding the numbers of un- known quantities in the Reynolds turbulence equations stem from the misunderstandings of physics of the Reynolds stress tensor. The current literatures have a consensus that the Reynolds stress tensor has six unknowns; however, this study shows that the Reynolds stress tensor actually has only three ones, namely the three components of fluctuation velocity. With this new understanding, the closed turbulence equations for incompressible flows are proposed.
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Physical Sciences, General & Theoretical Physics; Borsuk-Ulam theorem; antipodal points; quantum entanglement; holographic principle
Online: 23 September 2018 (01:29:55 CEST)
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The entangled antipodal points on black hole surfaces, recently described by t’Hooft, display an unnoticed relationship with the Borsuk-Ulam theorem. Taking into account this observation and other recent claims, suggesting that quantum entanglement takes place on the antipodal points of a S3 hypersphere, a novel framework can be developed, based on algebraic topological issues: a feature encompassed in an S2 unentangled state gives rise, when projected one dimension higher, to two entangled particles. This allows us to achieve a mathematical description of the holographic principle occurring in S2. Furthermore, our observations let us to hypothesize that a) quantum entanglement might occur in a four-dimensional spacetime, while disentanglement might be achieved on a motionless, three-dimensional manifold; b) a negative mass might exist on the surface of a black hole.
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Physical Sciences, General & Theoretical Physics; self-gravitation, black holes, neutrino stars
Online: 21 September 2018 (18:41:04 CEST)
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Due to limitation of the binding energy of a self-gravitating matter, the radius of a body is at least twice larger than the Schwarzschild radius. The total energy is adsorbed at the body surface, giving rise of a size-dependent surface tension. Since the Hawking temperature appears to be the critical one, the black holes possess zero surface tension. Microscopic neutrino stars are also introduced.
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Physical Sciences, Condensed Matter Physics; Bose gas, Bethe ansatz, threshold singularity
Online: 20 September 2018 (18:21:50 CEST)
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The one-dimensional gas of bosons interacting via a repulsive contact potential was solved long ago via Bethe's ansatz by Lieb and Liniger [Phys. Rev. {\bf 130}, 1605 (1963)]. The low energy excitation spectrum is a Luttinger liquid parametrized by a conformal field theory with conformal charge $c=1$. For higher energy excitations the spectral function displays deviations from the Luttinger behavior arising from the curvature terms in the dispersion. Adding a corrective term of the form of a mobile impurity coupled to the Luttinger liquid modes corrects this problem. The ``impurity'' term is an irrelevant operator, which if treated non-perturbatively, yields the threshold singularities in the one-particle and one-hole hole Green's function correctly. We show that the exponents obtained via the finite size corrections to the ground state energy are identical to those obtained through the shift function.
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Physical Sciences, Mathematical Physics; Minkowski space; spacetime; contravariant transformation; mixed basis; geometric interpretation; special relativity
Online: 20 September 2018 (17:21:21 CEST)
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A geometric interpretation of the Minkowski metric and thus of phenomena in special relativity is provided. It is shown that a change of basis in Minkowski space is the equivalent of a change of basis in Euclidean space if one basis element is replaced by its dual element. The methodology of the proof includes infinitesimal changes of basis using the Lie-algebras of the involved groups. As a consequence, a direct mapping between Euclidean and Minkowski space is defined.
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Physical Sciences, Applied Physics; Additive-Manufacturing, 3D Printing, Glass-Ceramics, Nanoscale, Laser 3D lithography, SZ2080, Cristobalite, Zirconia, Nanocomposites, Calcination
Online: 20 September 2018 (15:52:10 CEST)
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Fabrication of a true-3D inorganic ceramic with resolution down to nanoscale using sol-gel resist precursor is demonstrated. The method has an unrestricted free-form capability, control of the fill-factor, and high fabrication throughput. A systematic study of the proposed approach based on ultrafast laser 3D lithography of organic-inorganic hybrid sol-gel resin followed by a heat treatment enabled formation of inorganic amorphous and crystalline composites guided by the composition of the initial resin. The achieved resolution of 100 nm was obtained for 3D patterns of complex free-form architectures. Fabrication throughput of 50×103 voxels/s is achieved; voxel - a single volume element was recorded by a single pulse exposure. After a subsequent thermal treatment, ceramic phase was formed depending on the temperature and duration of the heat treatment as validated by Raman micro-spectroscopy. The X-ray diffraction (XRD) revealed a gradual emergence of the crystalline phases at higher temperatures with a signature of cristobalite SiO2, a high-temperature polymorph. Also, the tetragonal ZrO2 phase known for its high fracture strength was observed. This 3D nano-sintering technique is scalable from nano- to millimeter dimensions and opens a conceptually novel route for optical 3D nano-printing of various crystalline inorganic materials defined by an initial composition for diverse applications for microdevices in harsh physical and chemical environments and high temperatures.
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Physical Sciences, Other; standard interpretation; Bohmian mechanics; quantum uncertainty; determinism; subject-object relations; systems theory
Online: 20 September 2018 (07:40:07 CEST)
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For more than eighty years the standard interpretation (SI) has dominated quantum physics. Perspectives that have tried to challenge this domination have been remarkably unsuccessful. As a result, quantum theory (QT) has remained remarkably stagnant. The article offers a critical examination of SI and provides an explanation for its continued domination. It also uses Bohmian mechanics—a theoretical perspective advanced by American physicist David Bohm—as a case study for why alternative interpretations have failed to displace SI. The article sees the main reason for the failure to achieve much progress beyond SI in the unresolved philosophical problem of subject-object relation that continues to plague our study of physics. The article sketches a path to a possible solution and outlines a new science practice that this solution will require.
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Physical Sciences, General & Theoretical Physics; planck length; planck constant; newton's gravitational constant; compton frequency; schwarzschild radius
Online: 20 September 2018 (07:01:28 CEST)
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In modern physics, it is assumed that the Planck length is a derived constant from Newton's gravitational constant, the Planck constant and the speed of light, $l_p=\sqrt{\frac{G\hbar}{c^3}}$. This was first discovered by Max Planck in 1899. We suggest a way to find the Planck length independent of any knowledge of Newton's gravitational constant or the Planck constant, but still dependent on the speed of light (directly or indirectly).
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Physical Sciences, General & Theoretical Physics; uni ed theories; geometric uni cation; fermionic geometry; Cartan's principle of triality; complex space-time
Online: 19 September 2018 (10:34:16 CEST)
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We explore several ways, in order to include fermionic structures naturally in a physical theory in C4. We begin with the standard Dirac formalism and we proceed by using Cartan's property of triality as a second option. Afterwards, we suggest a new approach (in a preliminary basis), by introducing an 1-linear form, as the "square root of the geometry" derived by the usual 2-linear forms (quadratic forms). Keeping this way, we introduce n-linear forms, in order to formulate a new geometric structure, which could be suitable for the formulation of a pure geometric uni ed theory.
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Physical Sciences, General & Theoretical Physics; dynamic path; ADM formalism; complex space-time; extended space-time; uni ed theories; geometric uni cation
Online: 19 September 2018 (10:30:15 CEST)
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After developed the formulation of a "general relativity" in C4 [2], we proceed with the formulation of a Hamilton-Jacobi equation in C4. We argue that in this consideration, the usual problems of the ADM formalism, do not exist, due to the complex time as it exists in our consideration. Speci cally, we can derive a suitable dispersion relation in order to work with and nd a generalised super Hamiltonian
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Physical Sciences, General & Theoretical Physics; uni ed theories; complex space-time; gauge theories; particle theory; Higg's boson; geoemetric uni cation
Online: 19 September 2018 (10:26:17 CEST)
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We explore the possibility to nd the usual quantum theories, within the formulation of a classic theory of mechanics in C4. Speci cally, by releasing the end-point of the integral of the action derived in C4, we derive the dynamic path length of the geodesic equation in C4. In the at case, the derived Hamilton-Jacobi equations, were identi ed as the usual Klein-Gordon equation, where the complex functional action S(zi), is identi ed as the usual complex scalar field φ. Afterwards, we study the energy-momentum 4-d complex
vector, in order to re-establish the usual covariant derivative of gauge theories.
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Physical Sciences, General & Theoretical Physics; general relativity; geometric uni cation; dark matter-energy; mass geometrisation; complex space-time; symplectic space-time; extended space-time
Online: 19 September 2018 (10:21:48 CEST)
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We explore the field equations in a 4-d complex space-time, in the same way, that general relativity does for our usual 4-d real space-time, forming this way, a new "general relativity" in C4 space-time, free of sources. Afterwards, by embedding our usual 4-d real space-time in C4 space-time, we describe geometrically the energy-momentum tensor Tμν as the lost geometric information of this embedding. We further give possible explanation of dark eld and dark energy.
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Physical Sciences, General & Theoretical Physics; extended space-time; complex space-time; uni ed theories; geometric uni cation; dark matter-energy; Cartan's principle of triality;extended general-special relativity
Online: 19 September 2018 (10:18:55 CEST)
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We explore the possibility to form a physical theory in C4. We argue that the expansion of our usual 4-d real space-time to a 4-d complex space-time, can serve us to describe geometrically electromagnetism and unify it with gravity, in a different way that Kaluza-Klein theories do. Speci cally, the electromagnetic eld Aμ, is included in the free geodesic equation of C4. By embedding our usual 4-d real space-time in the symplectic 8-d real space-time (symplectic R8 is algebraically isomorphic to C4), we derive the usual geodesic equation of a charged particle in gravitational eld, plus new information which is interpreted. Afterwards, we explore the consequences of the formulation of a "special relativity" in the at R8.
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Physical Sciences, Mathematical Physics; relativistic quantum mechanics; Maxwell's electrodynamics; symmetrized Maxwell's equations; quaternionic quantum mechanics; telegraph equation; hall effect
Online: 19 September 2018 (06:26:00 CEST)
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An eigenvalue equation representing symmetric (dual) quantum equation is introduced. The particle is described by two scalar wavefunctions, and two vector wavefunctions. The eigenfunction is found to satisfy the quantum Telegraph equation keeping the form of the particle fixed but decaying its amplitude. An analogy with Maxwellian equations is presented. Massive electromagnetic field will satisfy a quantum Telegraph equation instead of a pure wave equation. This equation resembles the motion of the electromagnetic field in a conducting medium. With a particular setting of the scalar and vector wavefunctions, the dual quantum equations are found to yield the quantized Maxwell's equations. The total energy of the particle is related to the phase velocity ($v_p$) of the wave representing it by $E=p\,|v_p|$, where $p$ is the matter wave momentum. A particular solution which describes the process under which the particle undergoes a creation and annihilation is derived. The force acting on the moving particle is expressed in a dual Lorentz-like form. If the particle moves like a fluid, a dissipative (drag) quantum force will arise.
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Physical Sciences, Condensed Matter Physics; disordered system; two dimension; localization
Online: 18 September 2018 (07:37:29 CEST)
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In two dimensional disordered lattices, presence of interaction makes particles less localized than the non-interacting ones within the range of disorder strength W ≤ 4 and interaction strength V ≤ 4. If the interaction strength is higher, then particles localize more. Although, a localization-delocalization transition is not found, a transition with changes in the dominant correlations is observed. The nature of correlations between the particles as nearest neighbors become dominant beyond certain disorder strengths.
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Physical Sciences, Astronomy & Astrophysics; energy and angular momentum transfer; modified theories of gravity; anomalous increase of the astronomical unit
Online: 18 September 2018 (07:23:11 CEST)
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In this paper, we revisit a modified version of the classical Whitehead's theory of gravity in which all possible bilinear forms are considered to define the corresponding metric. Although, this is a linear theory that fails to give accurate results for the most sophisticated predictions of general relativity, such as gravity waves, it can still provide a convenient framework to analyze some new phenomena in the Solar System. In particular, recent development in the accurate tracking of spacecraft and the ephemerides of planetary positions have revealed certain anomalies in relation with our standard paradigm for celestial mechanics. Among them the so-called flyby anomaly and the anomalous increase of the astronomical unit play a prominent role. In the first case the total energy of the spacecraft changes during the flyby and a secular variation of the semi-major axis of the planetary orbits is found in the second anomaly. For this to happen it seems that a net energy and angular momentum transfer is taken place among the orbiting and the central body. We evaluate the total transfer per revolution for a planet orbiting the Sun in order to predict the astronomical unit anomaly in the context of Whitehead's theory. This could lead to a more deeply founded hypothesis for an extended gravity model.
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Physical Sciences, Astronomy & Astrophysics; astronomical data bases; catalogues; binaries: general; cataclysmic variables
Online: 17 September 2018 (14:53:07 CEST)
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Binary star DataBase (BDB) is the database of binary/multiple systems of various observational types. BDB contains data on physical and positional parameters of 260,000 components of 120,000 stellar systems of multiplicity 2 to more than 20, taken from a large variety of published catalogues and databases. We describe the new features in organization of the database, integration of new catalogues and implementation of new possibilities available to users. The development of the BDB index-catalogue, Identification List of Binaries, is discussed. This star catalogue provides cross-referencing between most popular catalogues of binary stars. We describe ideas and methods for reliable cross-identification of different entities (systems, pairs, components) in binary and multiple stellar systems.
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Physical Sciences, Fluids & Plasmas; Linear stability theory; Magneto convection; Through flow; Hele-Shaw cell; Galarkin method.
Online: 17 September 2018 (11:09:04 CEST)
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In this paper, an analytical investigation of the combined effect of through flow and magnetic field on the convective instability in an electrically conducting fluid layer, bounded in a Hele-Shaw cell is presented within the context of linear stability theory. The Galarkin method is utilized to solve the eigenvalue problem. The outcome of the important parameters on the stability of the system is examined analytically as well as graphically. It is observed that the through flow and magnetic field have both stabilizing effects, while the Hele-Shaw number has destabilizing effect on the stability of system. It is also found that the oscillatory mode of convection possible only when the magnetic Prandtl number takes the values less than unity.
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Physical Sciences, Optics; Gerdjikov Ivanov equation; integrability; chirped soliton
Online: 17 September 2018 (08:27:21 CEST)
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This paper secures the analytical soliton solutions of the perturbed NLSE gives to (1). The existence criteria have been demonstrated and the wave speed of the soliton befall out. To achieve all the results obtained we used the mathematical technique. In view of the results obtained, some new additional one have been reported in left-handed metamaterials.
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Physical Sciences, Astronomy & Astrophysics; supermassive black holes: non-thermal radiation; active galactic nuclei: BL lacertae objects: individual: J1043+2408; galaxies: jets; method: time series analysis
Online: 17 September 2018 (08:00:08 CEST)
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Search for periodic signals from blazars has become widely discussed topic in recent years. This is because periodic signals bear imprints of the processes occurring near the innermost regions of blazars which are mostly inaccessible to our direct view. Such signals provide insights into various aspect of blazar studies including disk-jet connection, magnetic field configuration and, more importantly, strong gravity near the supermassive black holes and release of gravitational waves from the binary supermassvie black hole systems. In this work, we report detection of a periodic signal in the radio light curves of the blazar J1043+2408 spanning ~10.5 years. We performed multiple methods of time series analysis, namely, epoch folding, Lomb-Scargle periodogram, and discrete auto-correlation function. All three methods consistently reveal a repeating signal with a periodicity of ~563 days. To robustly account for the red-noise processes usually dominant in the blazar variability and other possible artifacts, a large number of Monte Carlo simulations were performed. This allowed us to estimate a high significance (99.9% local and 99.4% global) against possible spurious detection. As possible explanations, we discuss a number of scenarios including binary supermassive black hole system, Lense-Thirring precession, and jet swing and precession.
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Physical Sciences, Mathematical Physics; electromagnetism; topology; charge-conservation; constitutive relations; gauge freedom
Online: 16 September 2018 (10:12:22 CEST)
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A careful examination of the fundamentals of electromagnetic theory shows that due to the underlying mathematical assumptions required for Stokes' Theorem, charge conservation cannot be guaranteed in topologically non-trivial spacetimes. However, in order to break the charge conservation mechanism we must also allow the electromagnetic excitation fields DH to possess a gauge freedom, just as the electromagnetic scalar and vector potentials $\varphi$ and $\emVec{A}$ do. This has implications for the treatment of electromagnetism in spacetimes where black holes both form and then evaporate, as well as extending the possibilities for treating vacuum polarisation. Using this gauge freedom of DH we also propose an alternative to the accepted notion that a charge passing through a wormhole necessarily leads to an additional (effective) charge on the wormhole's mouth.
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Physical Sciences, General & Theoretical Physics; Phase space volume, formal group theory, entropy
Online: 13 September 2018 (18:08:39 CEST)
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The entropy of Boltzmann-Gibbs, as proved by Shannon and Khinchin, is based on four axioms, where the fourth one concerns additivity.
The group theoretic entropies make use of formal group theory to replace this axiom with a more general composability axiom.
As has been pointed out before, generalized entropies crucially depend on the number of allowed number degrees of freedom $N$.
The functional form of group entropies is restricted (though not uniquely determined) by assuming extensivity on the equal probability ensemble,
which leads to classes of functionals corresponding to sub-exponential, exponential or super-exponential dependence of the phase space volume $W$ on $N$.
We review the ensuing entropies, discuss the composability axiom, relate to the Gibbs' paradox discussion and explain why group entropies may be particularly relevant
from an information theoretic perspective.
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Physical Sciences, Other; Entanglement; EPR Paradox; ER = EPR conjecture; GR = QM; Locality; Theory of Everything; Quantum Communications
Online: 12 September 2018 (15:38:14 CEST)
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During the last century, entanglement was the bone of contention between the two main pillars of Physics: General Relativity (GR) and Quantum Mechanics (QM). This began in 1935 with the Einstein-Podolsky-Rosen paradox (EPR paradox) which concluded that although Quantum Mechanics is not wrong, it is an incomplete theory to represent physical reality. In this paper it is demonstrated that some byproducts resulting from entanglement and which we will call avatars act as a hinge that link both theories making the completeness of QM clear. Moreover, a thorough analysis of the non-locality of this effect will be carried out. Besides, it is demonstrated that entanglement is an instantaneous phenomenon and that it does not require the use of a superluminal signaling for this purpose. Finally, the avatars will also appear in each wormhole resulting from an entanglement process (WREP) demonstrating that they are traversable with an equivalent path of null length which can be crossed in a null time with all that this implies in Quantum Communications.
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Physical Sciences, General & Theoretical Physics; Bell-inequalities; quantum nonlocality; computer simulations of Bell tests; local causality; contextuality loophole; photon identification loophole
Online: 12 September 2018 (03:06:46 CEST)
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Bell type inequalities are proven using oversimplified probabilistic models and/or counterfactual definiteness (CFD). If setting-dependent variables describing measuring instruments are correctly introduced none of these inequalities may be proven. In spite of this a belief in a mysterious quantum nonlocality is not fading. Computer simulations of Bell tests allow studying different scenarios how the experimental data might have been created. They allow also to generate outcomes of various counterfactual experiments such as repeated or simultaneous measurements performed in different settings on the same ‘’ photon-pair” etc. They allow reinforcing or relaxing CFD- compliance and /or to study the impact of various “photon identification procedures” mimicking those used in real experiments. Using a specific setting- dependent identification procedure data samples consistent with quantum predictions may be generated. It reflects an active role of instruments during the measurement process. Each setting dependent data samples are consistent with specific setting –dependent probabilistic models which may not be deduced using non-contextual local realistic or stochastic hidden variables. In this paper we discuss the results of these simulations. Since the data samples are generated in a locally causal way, these simulations provide additional strong arguments for closing the door on quantum nonlocality
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Physical Sciences, Astronomy & Astrophysics; general relativity; past lightcone gauge; direct observational approach; cosmological observables; galaxy surveys; galaxy number count; density contrast; overdensity; cosmological perturbations
Online: 11 September 2018 (10:08:39 CEST)
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The lightcone gauge is a set of what are called the observational coordinates adapted to our past lightcone. We develop this gauge by producing a perturbed spacetime metric that describes the geometry of our past lightcone where observations are usually obtained. We connect the produced observational metric to the perturbed Friedmann-Lema\^itre-Robertson-Walker metric in the standard general gauge or what is the so-called 1+3 gauge. We derive the relations between these perturbations of spacetime in the observational coordinates and those perturbations in the standard metric approach, as well as the dynamical equations for the perturbations in observational coordinates. We also calculate the observables in the lightcone gauge and re-derive them in terms of Bardeen potentials to first order. A verification is made of the observables in the perturbed lightcone gauge with those in the standard gauge. The advantage of the method developed is that the observable relations are simpler than in the standard formalism, and they are expressed in terms of the metric components which in principle are measurable. We use the perturbed lightcone gauge in galaxy surveys and the calculations of galaxy number density contrast. The significance of the new gauge is that by considering the null-like light propagations the calculations are much simpler due to the non-consideration of the angular deviations.
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Physical Sciences, Acoustics; ultrasonic lens; apodization; Soret zone plate
Online: 11 September 2018 (06:40:19 CEST)
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The image performance of acoustic and ultrasound sensors depends on several fundamental parameters such as depth of focus or spatial resolution. There are currently two different type of acoustic diffractive lenses: those which form a diffraction-limited spot with a shallow depth of focus (zone plates) and lenses which form an extended focus (quasi-Bessel beams). In this paper, we investigate a pupil-masked Soret zone plate which allows the tunability of a normalized angular spectrum. It is shown that the depth of focus and the spatial resolution can be modified, without changing the lens structure, by choosing the size of the amplitude pupil mask. This effect is based on the transformation of spherically converging waves into quasi-conical waves, due to the apodization of the central part of the zone plate. The theoretical analysis is verified with both numerical simulations and experimental measurements. A Soret zone plate immersed in water with D/2F=2.5 and F=4.5$\lambda$, changes its depth of focus from 2.84$\lambda$ to 5.9$\lambda$ and the spatial resolution increases from 0.81$\lambda$ to 0.64$\lambda$ at a frequency of 250 kHz, by modifying the pupil mask dimensions of the Soret zone plate.
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Zdeněk Pilát,
Martin Kizovský,
Jan Ježek,
Stanislav Krátký,
Jaroslav Sobota,
Martin Šiler,
Ota Samek,
Tomáš Buryška,
Pavel Vaňáček,
Jiří Damborský,
Zbyněk Prokop,
Pavel Zemánek
Physical Sciences, Applied Physics; surface enhanced Raman spectroscopy; microfluidics; Klarite 312; chloroalkane; 1,2,3-trichloropropane
Online: 10 September 2018 (11:47:52 CEST)
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Optofluidics, a research discipline combining optics with microfluidics, currently aspires to revolutionize the analysis of biological and chemical samples e.g. for medicine, pharmacology, or molecular biology. In order to detect low concentrations of analytes in water, we developed an optofluidic device containing a nanostructured substrate for surface enhanced Raman spectroscopy (SERS). The geometry of the gold surface allows localized plasmon oscillations to give rise to the SERS effect, in which the Raman spectral lines are intensified by the interaction of the plasmonic field with the electrons in the molecular bonds. The SERS substrate was enclosed in a microfluidic system, which allowed transport and precise mixing of the analyzed fluids, while preventing contamination or abrasion of the highly sensitive substrate. To illustrate its practical use, we employed the device for quantitative detection of persistent environmental pollutant 1,2,3-trichloropropane in water in submillimolar concentrations. The developed sensor allows fast and simple quantification of halogenated compounds and it will contribute towards the environmental monitoring and enzymology experiments with engineered haloalkane dehalogenase enzymes.
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Physical Sciences, Astronomy & Astrophysics; Lorentz invariance; Standard-Model extension; polarization; Active Galactic Nuclei; Gamma-ray Bursts
Online: 9 September 2018 (11:04:03 CEST)
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Theories of quantum gravity suggest that Lorentz invariance, the fundamental symmetry of the Theory of Relativity, may be broken at the Planck energy scale. While any deviation from conventional Physics must be minuscule in particular at attainable energies, this hypothesis motivates ever more sensitive tests of Lorentz symmetry. In the photon sector, astrophysical observations, in particular polarization measurements, are a very powerful tool because tiny deviations from Lorentz invariance will accumulate as photons propagate over cosmological distances. The Standard-Model Extension (SME) provides a theoretical framework in the form of an effective field theory that describes low-energy effects due to a more fundamental quantum gravity theory by adding additional terms to the Standard Model Lagrangian. These terms can be ordered by the mass dimension d of the corresponding operator and lead to a wavelength, polarization, and direction dependent phase velocity of light. In this paper, we analyze optical polarization measurements from 63 Active Galactic Nuclei (AGN) and Gamma-ray Bursts (GRBs) in order to search for Lorentz violating signals. We derive the first set limits on each of the 10 individual birefringent coefficients of the minimal SME with d = 4, with 95% confidence limits on the order of 10−34 on the dimensionless coefficients.
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Physical Sciences, Optics; Surface plasmon, Airy beam, photonic hook, curved wave, flatland photonics
Online: 6 September 2018 (13:05:48 CEST)
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It is well-known that surface plasmon wave propagates along a straight line, but this common sense was broken by the artificial curved light – plasmon Airy beam. In this paper, we introduce a new class of curved surface plasmon wave - the photonic hook plasmon. It propagates along wavelength scaled curved trajectory with radius less than surface plasmon polariton wavelength, and can exist despite the strong energy dissipation at the metal surface.
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Physical Sciences, Particle & Field Physics; Quantum mechanics; General and special relativity theories; Origins of the energy and mass; Space-time volume and distance; Origin of quantum wave function; Three-dimensional quantized spaces; Quantum entanglement; Space-time curvatures and quantum metrics
Online: 5 September 2018 (14:40:06 CEST)
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Three-dimensional quantized space model is newly introduced. Quantum mechanics and relativity theory are explained in terms of the warped three-dimensional quantized spaces with the quantum time width (Dt=tq). The energy is newly defined as the 4-dimensional space-time volume of E = cDtDV in the present work. It is shown that the wave function of the quantum mechanics is closely related to the warped quantized space shape with the space time-volume. The quantum entanglement and quantum wave function collapse are explained additionally. The special relativity theory is separated into the energy transition associated with the space-time shape transition of the matter and the momentum transition associated with the space-time location transition. Then, the quantum mechanics and the general relativity theory are about the 4-dimensional space-time volume and the 4-dimensional space-time distance, respectively.
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Physical Sciences, General & Theoretical Physics; Heisenberg's uncertainty principle; certainty; wave function; Planck scale; Planck mass; Planck particle; Bell's Inequality; superposition; entropy; Compton clock
Online: 5 September 2018 (11:34:51 CEST)
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In this paper, we will revisit the derivation of Heisenberg's uncertainty principle. We will see how the Heisenberg principle collapses at the Planck scale by introducing a minor modification. The beauty of our suggested modification is that it does not change the main equations in quantum mechanics; it only gives them a Planck scale limit where uncertainty collapses. We suspect that Einstein could have been right after all, when he stated, ``God does not throw dice." His now-famous saying was an expression of his skepticism towards the concept that quantum randomness could be the ruling force, even at the deepest levels of reality. Here we will explore the quantum realm with a fresh perspective, by re-deriving the Heisenberg principle in relation to the Planck scale. We will show how this idea also leads to an upper boundary on uncertainty, in addition to the lower boundary. These upper and lower boundaries are identical for the Planck mass particle; in fact, they are zero, and this highlights the truly unique nature of the Planck mass particle. Further, there may be a close connection between light and the Planck mass particle: In our model, the standard relativistic energy momentum relation also seems to apply to light, while in modern physics light generally stands outside the standard relativistic momentum energy relation. We will also suggest a new way to look at elementary particles, where mass and time are closely related, consistent with some of the recent work in experimental physics. Our model leads to a new time operator that does not appear to be in conflict with the Pauli objection. This indicates that both mass and momentum come in quanta, which are perfectly correlated to an internal Compton `clock' frequency in elementary particles.
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Physical Sciences, Atomic & Molecular Physics; photoacoustic spectroscopy; PAS; hydrocarbons; optical-parametric oscillator; OPO; gas sampling; spectral deconvolution; EUREQA
Online: 5 September 2018 (06:01:48 CEST)
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Photoacoustic spectroscopy allows the identification of specific molecules in gases. We evaluate the spectral resolution and detection limits for a PAS system in the broadband infrared wavelength region 3270 nm ≲ λ ≲ 3530 nm driven by a continuous wave optical parametric oscillator with P ≈ 1.26 W by measuring the absorption of diluted propane, ethane and methane test gases at low concentrations c ~ 100 ppm for ~1350 discrete wavelengths λi. The resulting spectra IPAS(λi) were compared to the high resolution cross section data σFTIR obtained by Fourier Transform Infrared Spectroscopy from the HITRAN database. Deviations as little as 7.1(6)% for propane, 8.7(11)% for ethane and 15.0(14)% for methane with regard to the average uncertainty between IPAS(λi) and the expected reference values based on σFTIR were recorded. The wavelengths λres of the characteristic absorption lines can be pinpointed with a high relative accuracy <5 × 10−5 corresponding to a resolution of λres ~ 0.16 nm. Detection limits range between 7.1 ppb (ethane) to 13.6 ppb (methane) coinciding with high experimental signal-to-noise ratios. Moreover, using EUREQA, an artificial intelligence program, simulated mixed gas samples at low limits of detection could be deconvoluted. These results justify a further development of PAS technology to support, e.g., biomedical research.
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Physical Sciences, Other; entanglement; quantum computation; quantum communication
Online: 5 September 2018 (05:56:20 CEST)
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In this paper, I propose new models of quantum information processing using the exchange interaction in physical systems. The partial SWAP operator that can be realized using the exchange interaction is used as the underlying resource for defining models of quantum computation, quantum communication, quantum memory and decoherence-free subspaces. Given the non-commutativity of these operators (for adjacent operators operating on a common qubit), a number of quantum states and entanglement patters can be obtained. This zoo of states can be classified, due to the parity constraints and permutation symmetry of the states, into invariant subspaces that are used for the definition of some of the applications in this paper.
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Physical Sciences, Applied Physics; AFM, photothermal excitation, off-resonance tapping,
high-speed atomic force microscopy, live cell imaging, antimicrobial peptide, thrombocytes, bacterial imaging, cell lysis
Online: 4 September 2018 (14:25:20 CEST)
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Imaging living cells by atomic force microscopy (AFM) promises not only high-resolution topographical data, but additionally, mechanical contrast, which are not obtainable with other microscopy techniques. Such imaging is however challenging, as cells need to be measured with low interaction forces to prevent either deformation or detachment from the surface. Off-resonance modes which periodically probe the surface have been shown to be advantageous, as they provide excellent force control combined with large amplitudes, which help reduce lateral force interactions.
However, the low actuation frequency in traditional off-resonance techniques limits the imaging speed significantly. Using photothermal actuation, we probe the surface by directly actuating the cantilever. Due to the much smaller mass that needs to be actuated, the achievable measurement frequency is increased by two orders of magnitude. Additionally, photothermal off-resonance tapping retains the precise force control of conventional off-resonance modes and is therefore well suited to gentle imaging. Here we show how photothermal off-resonance tapping can be used to study live cells by AFM. As an example of imaging mammalian cells, the initial attachment, as well as long term detachment of a human thrombocytes are presented. The membrane disrupting effect of the antimicrobial peptide CM-15 is shown on the cell wall of E. coli. Finally, the dissolution of the cell wall of B. subtilis by lysozyme is shown. Taken together, these evolutionarily disparate forms of life exemplify the usefulness of PORT for live cell imaging in a multitude of biological disciplines.
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Physical Sciences, Other; landuse change; climate change; garden city model; green vegetation; Landsat; urban heat island
Online: 4 September 2018 (08:28:33 CEST)
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The key anthropogenic effects on climate include the changes in land use and emission of greenhouse gases into the atmosphere. Depletion of vegetation poses serious threat that speeds the process of climate change and reduces carbon sequestration by the environment. Thus, the preservation of natural environment in urban areas is an essential component of the garden city model, proposed by Sir Ebenezer Howard in 1898, to ensure ecological balance. Recent Landsat images showed that Kumasi does not have the required percentage of green vegetation as was stipulated in the garden city model on which the city was built. It was observed that most parts of Kumasi's green vegetation have been lost to built environments. This study was conducted to assess the impact of urbanization on the garden city status and its effect on the micro-climate of the city. Significant changes in the vegetation cover of the city was evaluated from Landsat-TM imagery and analysis of a long term climatic data of Kumasi carried out over a 55-year period (1960 to 2015). It was observed that, climatic conditions have slightly changed, as mean surface temperature of has increased by 1.2 °C/ 55 years, due to the significant landuse changes from development of non-transpiring, reduced evaporative urban surfaces. However, the impact is not greatly felt due to the geographical location of the city on the globe despite the evidence of a considerable temperature change. Green vegetation conservation for the city is recommended as a top priority in future for city authorities and planners.
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Physical Sciences, Condensed Matter Physics; metal-insulator transitions; electronic transport in interface structures; quantum hall effects
Online: 4 September 2018 (08:03:44 CEST)
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The apparent metal-insulator transition (MIT) in two-dimension (2D) was discovered by Kravchenko et al. [1] more than two decades ago in strongly interacting 2D electrons residing in a Si-metal-oxide-semiconductor field-effect transistor (Si-MOSFET). Its origin remains unresolved. Recently, low magnetic field reentrant insulating phases (RIPs), which dwell between the zero-field (B=0) metallic state and the integer quantum Hall (QH) states where the Landau-level filling factor υ > 1, have been observed in strongly correlated 2D GaAs hole systems with large interaction parameter rs (~20-40) and high purity. A new complex phase diagram was proposed, which includes zero field MIT, low magnetic field RIPs, integer QH states, fractional QH states, high field RIPs and insulating phases (HFIPs) with υ < 1 in which the insulating phases are explained by the formation of Wigner crystal. Furthermore, evidences of new intermediate phases were reported. All contribute to the further understandings of the puzzle. This review article serves the purpose of summarizing those recent experimental findings and theoretical endeavors, to foster future research efforts.
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Physical Sciences, Applied Physics; plasma membrane; spontaneous curvature; Helfrich energy; area difference elastic model; protein crowding; Deviatoric curvature
Online: 4 September 2018 (07:13:10 CEST)
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In order to alter and adjust the shape of the membrane, cells harness various mechanisms of curvature generation. Many of these curvature generation mechanisms rely on the interactions between peripheral membrane proteins, integral membrane proteins, and lipids in the bilayer membrane. One of the challenges in modeling these processes is identifying the suitable constitutive relationships that describe the membrane free energy that includes protein distribution and curvature generation capability. Here, we review some of the commonly used continuum elastic membrane models that have been developed for this purpose and discuss their applications. Finally, we address some fundamental challenges that future theoretical methods need to overcome in order to push the boundaries of current model applications.
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Physical Sciences, General & Theoretical Physics; Einstein; manifold; Hilbert space; Abelian; dagger category
Online: 3 September 2018 (12:51:51 CEST)
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The unexploited unification of general relativity and quantum physics is a painstaking issue that prevents physicists to properly understanding the whole of Nature. Here we propose a pure mathematical approach that introduces the problem in terms of group theory. Indeed, we build a cyclic groupoid (a nonempty set with a binary operation defined on it) that encompasses both the theories as subsets, making it possible to join together two of their most dissimilar experimental results, i.e., the commutativity detectable in our macroscopic relativistic world and the noncommutativity detectable in the quantum, microscopic world. This approach, combined with the Connes fusion operator, leads to a mathematical framework useful in the investigation of relativity/quantum mechanics relationships.
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Physical Sciences, Mathematical Physics; Weyl-Heisenberg group; affine group; weyl quantization; wigner function; covariant integral quantization
Online: 3 September 2018 (08:01:25 CEST)
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Any quantization maps linearly functions on a phase space to symmetric operators in a Hilbert space. Covariant integral quantization combines operator-valued measure with symmetry group of the phase space. Covariant means that the quantization map intertwines classical (geometric operation) and quantum (unitary transformations) symmetries. Integral means that we use all ressources of integral calculus, in order to implement the method when we apply it to singular functions, or distributions, for which the integral calculus is an essential ingredient. In this paper we emphasize the deep connection between Fourier transform and covariant integral quantization when the Weyl-Heisenberg and affine groups are involved. We show with our generalisations of the Wigner-Weyl transform that many properties of the Weyl integral quantization, commonly viewed as optimal, are actually shared by a large family of integral quantizations.
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Physical Sciences, Astronomy & Astrophysics; accelerated frames; galactic rotation curve; dark matter
Online: 31 August 2018 (12:00:39 CEST)
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In this article the galactic rotation curve is analyzed as an effect of an accelerated reference frame. This phenomenon is the strongest evidence for the so called dark matter. We show that a non-inertial reference frame could explain the experimental data. We also show that general relativity is not enough to complete explain that which encouraged alternatives paths such as the MOND approach. Considering the effect of dark matter as a realization of accelerated reference frames is a simple but powerful hypothesis.
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Physical Sciences, General & Theoretical Physics; quantum mechanics; bohmian quantum mechanics; quantum potential; schrodinger equation; dirac equation; klein-gordon equation; spin
Online: 31 August 2018 (07:39:53 CEST)
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By expressing the Schrödinger wave function in the form , where R and S are real functions, we have shown that the expectation value of S is conserved. The amplitude of the wave (R) is found to satisfy the Schrödinger equation while the phase (S) is related to the energy conservation. Besides the quantum potential that depends on R, viz., , we have obtained a spin potential that depends on S which is attributed to the particle spin. The spin force is found to give rise to dissipative viscous force. The quantum potential may be attributed to the interaction between the two subfields S and R comprising the quantum particle. This results in splitting (creation/annihilation) of these subfields, each having a mass with an internal frequency of , satisfying the original wave equation and endowing the particle its quantum nature. The mass of one subfield reflects the interaction with the other subfield. If in Bohmian ansatz R satisfies the Klein-Gordon equation, then S must satisfies the wave equation. Conversely, if R satisfies the wave equation, then S yields the Einstein relativistic energy momentum equation.
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Physical Sciences, Astronomy & Astrophysics; Cosmological Constant; MOND; dark matter; antigravity
Online: 31 August 2018 (07:24:08 CEST)
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By solving the weak field limit of Einstein’s Field Equation including the Cosmological Constant, under the constraint of spherical isotropy, it is shown that, at large cosmological distance, the gravitational force exceeds the one that is predicted by Newton’s gravity law, such that it corresponds with Milgrom’s MOND hypothesis. However, the resulting prediction that, at extremely large distances, gravity with some spatial periodicity turns on-and-off into antigravity marks a decisive difference.
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Physical Sciences, Fluids & Plasmas; inertial focusing; dean flow; serpentine; fsi; two-way coupling
Online: 30 August 2018 (13:59:05 CEST)
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The dynamics of a spherical particle in an asymmetric serpentine is studied by finite element method (FEM) simulations in a physically unconstrained system. The two-way coupled time dependent solutions illustrate the path of the particle along a curve where a secondary flow (Dean flow) has developed. The simulated conditions were adjusted to match those of an experiment for which particles were focused under inertial focusing conditions. The obtained rotational modes allowed to infer the influence of the local flow around the particle. We propose a new approach to find the decoupled secondary flow contribution employing a quasi-Stokes flow.
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Physical Sciences, Optics; Quantum Rayleigh spontaneous emission, photon polarization states, polarization correlations.
Online: 30 August 2018 (13:31:24 CEST)
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The interpretation of published experimental results intended to prove the existence of a quantum phenomenon of non-locality involving photonic entangled states did not take into consideration the existence of the quantum Rayleigh conversion of photons in dielectric media. This phenomenon leads to the existence of high levels of correlations between two independent photonic and linearly polarized quantum states generated after the entangled photons have been absorbed through the quantum Rayleigh conversion. Both pure and mixed individual states of polarization result in expressions normally associated with entangled photonic states, providing support for the view that the physical reality of quantum non-locality is highly questionable.
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Physical Sciences, General & Theoretical Physics; Einstein's equation; gravitation; general relativity; sink; gravitational aether
Online: 30 August 2018 (08:20:25 CEST)
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J. C. Maxwell, B. Riemann and H. Poincaré have proposed the idea that all microscopic particles are sink flows in a fluidic aether. Following this research program, a previous theory of gravitation based on a mechanical model of vacuum and a sink flow model of particles is generalized by methods of special relativistic continuum mechanics. In inertial coordinate systems, we construct a tensorial potential which satisfies the wave equation. Inspired by the equation of motion of a test particle, a definition of a metric tensor of a Riemannian spacetime is introduced. Applying Fock's theorem, a generalized Einstein's equation is derived based on some assumptions. This equation reduces to Einstein's equation in case of weak field in harmonic coordinate systems. In some special non-inertial coordinate systems, a second generalized Einstein's equation is derived based on some assumptions. If the field is weak and the coordinate system is quasi-inertial and harmonic, the second generalized Einstein's equation reduces to Einstein's equation. Thus, this theory also explains all the experiments that support the theory of general relativity. There exists some fundamental differences between this theory and Einstein's theory of general relativity.
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Physical Sciences, Particle & Field Physics; black holes; loop quantum gravity
Online: 29 August 2018 (10:26:06 CEST)
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The understanding of black holes in loop quantum gravity is becoming increasingly accurate. This review focuses on the possible experimental or observational consequences of the underlying spinfoam structure of space-time. It adresses both the aspects associated with the Hawking evaporation and the ones due to the possible existence of a bounce. Finally, consequences for dark matter and gravitational waves are considered.
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Physical Sciences, Other; spectroscopy; plasma diagnostics
Online: 29 August 2018 (08:16:51 CEST)
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We describe electron temperature measurements in the SSX MHD wind tunnel using two different methods. First, we estimate Te along a chord by measuring the ratio of the C_III 97.7 nm to CIV 155 nm line intensities using a vacuum ultraviolet monochrometer. Second, we record a biasing scan to a double Langmuir probe to obtain a local measurement of Te. The aim of these studies is to increase the Taylor state lifetime, primarily by increasing the electron temperature. Also, a model is proposed to predict magnetic lifetime of relaxed states and is found of predict the lifetime satisfactorily. Furthermore, we find that proton cooling can be explained by equilibration with the electrons.
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Physical Sciences, General & Theoretical Physics; Bouncing oil droplets; Stochastic quantum dynamics; de Broglie–Bohm theory; Quantum non-equilibrium; H-theorem; Ergodicity
Online: 28 August 2018 (13:34:09 CEST)
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Recently, the properties of bouncing oil droplets, also known as `walkers', have attracted much attention because they are thought to offer a gateway to a better understanding of quantum behaviour. They indeed constitute a macroscopic realization of wave-particle duality, in the sense that their trajectories are guided by a self-generated surrounding wave. The aim of this paper is to try to describe walker phenomenology in terms of de Broglie-Bohm dynamics and of a stochastic version thereof. In particular, we first study how a stochastic modification of the de Broglie pilot-wave theory, à la Nelson, affects the process of relaxation to quantum equilibrium, and we prove an H-theorem for the relaxation to quantum equilibrium under Nelson-type dynamics. We then compare the onset of equilibrium in the stochastic and the de Broglie-Bohm approaches and we propose some simple experiments by which one can test the applicability of our theory to the context of bouncing oil droplets. Finally, we compare our theory to actual observations of walker behavior in a 2D harmonic potential well.
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Physical Sciences, General & Theoretical Physics; symmetry; time; space; entropy; bijective analysis; supersymmetry
Online: 28 August 2018 (13:11:11 CEST)
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Bijective Analysis of 4D Minkowski space-time model confirms that 4D space-time where time would be 4th dimension of space does not exist. In 4D manifold, time is the duration of a physical event which runs in space. An event does not have the duration in time, duration itself is time. It means that any given physical phenomena can only be symmetric in space; not in time.
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Physical Sciences, Optics; Second harmonic generation, Mie resonances, all-dielectric nanoparticles
Online: 23 August 2018 (13:31:14 CEST)
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We design an asymmetric nonlinear optical nanoantenna composed of a dielectric nanodisk and an adjacent nanobar. The proposed composite structure made of AlGaAs exhibits resonant response at both the fundamental and doubled frequencies. Being driven by the strong magnetic dipole resonance at the pump wavelength and a high-quality mode at the harmonic wavelength, the efficient second-harmonic radiation is generated predominantly along the vertical directions under the normally incident plane-wave excitation.
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Physical Sciences, Applied Physics; vacuum pressure; triple vacuum glazing; finite element modelling; thermal performance; towards zero-energy buildings
Online: 23 August 2018 (08:35:23 CEST)
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Long-term durability of the vacuum edge-seal plays a significant part in retrofitting triple vacuum glazing (TVG) to existing buildings in achieving towards zero-energy buildings (ZEB) target. Vacuum pressure decrement with respect to time between panes affect the thermal efficiency of TVG. This study reports a 3D finite element model, with validated mathematical methods and comparison, for the assessment of the influence of vacuum pressure diminution on the thermal transmittance (U value) of TVG. The centre-of-pane and total U values of TVG calculated to be 0.28 Wm−2K−1 and 0.94 Wm−2K−1 at the cavity vacuum pressure of 0.001 Pa. The results suggests that a rise in cavity pressure from 0.001 Pa to 100 kPa increases the centre-of-pane and total U values from 0.28 Wm−2K−1 and 0.94 Wm−2K−1 to 2.4 Wm−2K−1 and 2.58 Wm−2K−1, respectively. The temperature descent on the surfaces of TVG between hot and cold sides’ increases by decreasing the cavity vacuum pressure from 50 kPa to 0.001 Pa. To maintain the cavity vacuum pressure of 0.001 Pa for over 20 years of life span in the cavity of 10 mm wide edge sealed triple vacuum glazing, non-evaporable getters will maintain the cavity vacuum pressure that will enable the long-term durability to TVG.
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Physical Sciences, Mathematical Physics; Schelling Model; Spatial Analysis; Entropy
Online: 22 August 2018 (13:21:05 CEST)
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The Schelling model of segregation allows for a general description of residential movements in an environment modeled by a lattice. The key factor is that occupants change positions until they are surrounded by a designated minimum number of similarly labeled residents. An analogy to the Ising model has been made in previous research, primarily due the assumption of state changes being dependent upon the adjacent cell positions. This allows for concepts produced in statistical mechanics to be applied to the Schelling model. Here is presented a methodology to estimate the entropy of the model for different states of the simulation. A Monte Carlo estimate is obtained for the set of macrostates defined as the different aggregate homogeneity satisfaction values across all residents, which allows for the entropy value to be produced for each state. This produces a trace of the estimated entropy value for the states of the lattice configurations to be displayed with each iteration. The results show that the initial random placements of residents have larger entropy values than the final states of the simulation when the overall homogeneity of the residential locality is increased.
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Physical Sciences, Applied Physics; quality control; BSRN; solar radiation; satellite-retrieve irradiance; ground stations; validation
Online: 21 August 2018 (06:23:52 CEST)
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Quality control (QC) may be a lengthy and tedious process. As a result, most data users use data from meteorological services without performing data quality checks. The South African Weather Service (SAWS) re-established the national solar radiometric network comprising of 13 new stations within the six climatic zones of the country. This study reports on the performance results of the Baseline Surface Radiation Network (BSRN) QC procedures applied to the solar radiation data within the SAWS radiometric network. The overall percentage performance of the SAWS solar radiation network based on BSRN QC methodology is 97.79%, 93.64%, 91.6% and 92.23% for Long Wave Downward Irradiance (LWD), Global Horizontal Irradiance (GHI), Diffuse Horizontal Irradiance (DHI) and Direct Normal Irradiance (DNI) respectively with operational problems largely dominating the percentage of bad data. The overall average performance of the Surface Solar Radiation Dataset – Heliosat (SARAH) data records for the GHI estimation for all the stations showed a Mean Bias Deviation (MBD) of -8.28 Wm-2, a Mean Absolute Deviation (MAD) of 9.06 Wm-2 and the Root Mean Square Deviation (RMSD) of 11.02 Wm-2. The correlation (quantified by R2) between ground-based and SARAH-derived GHI time series was ~ 0.98. The established network has the potential of providing high quality minute solar radiation data sets (GHI, DHI, DNI and LWD) and auxiliary hourly meteorological parameters vital for scientific and practical applications in renewable energy technologies in South Africa.
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Physical Sciences, Condensed Matter Physics; quantum thermodynamics; quantum Rabi model; isoenergetic cycle
Online: 18 August 2018 (08:10:27 CEST)
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The isoenergetic cycle is a purely mechanical cycle comprised of adiabatic and isoenergetic processes. In the latter the system interacts with an energy bath keeping constant the expectation value of the Hamiltonian. This cycle has been mostly studied in systems consisting of particles confined in a power-law trap. In this work we study the performance of the isoenergetic cycle for a system described by the quantum Rabi model for the case of controlling the coupling strength parameter, the resonator frequency and the two-level system frequency. For the cases of controlling either the coupling strength parameter or the resonator frequency, we find that it is possible to closely approach to maximal unit efficiency when the parameter is sufficiently increased in the first adiabatic stage. In addition, for the first two cases the maximal work extracted is obtained at parameter values corresponding to high efficiency which constitutes an improvement over current proposals of this cycle.