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Model Higgs Bundles in Exceptional Components of the Sp(4,R)-Character Variety
Get PDFWe establish a gluing construction for Higgs bundles over a connected sum of Riemann surfaces in terms of solutions to the Sp(4,R)-Hitchin equations using the linearization of a relevant elliptic operator. The construction can be used to provide model Higgs bundles in all the 2g-3 exceptional components of the maximal Sp(4,R)-Higgs bundle moduli space, which correspond to components solely consisted of Zariski dense representations. This alsoallows a comparison between the invariants for maximal Higgs bundles and the topological invariants for Anosov representations constructed by O. Guichard and A. Wienhard
Some Remarks on a Class of Finite Projective Klingenberg Planes
Get PDFIn this article, we deal with a class of projective Klingenberg planes constructed over a plural algebra of order m. Thanks to this, the incidence matrices for some special cases of the class are obtained. Next, the number of collineations of the certain classes are found. Besides, an example of a collineation for these classes are given. Finally, we achieve to carry the obtained results to more general case
Symmetry problem 1
Get PDFA symmetry problem is solved. A new method is used. The idea of this methodis to reduce to a contradiction the PDE and the over-determined boundary data on the boundary.The new method allows one to solve other symmetry problems
Electrode Processes in Electrochromic Anodic Oxide Films on Niobium
Get PDFWe review the following issues: peculiarities of polycrystalline AOP development at niobium in nitrate salt melt at temperatures of Nb2O5 recrystallization, the mechanisms of change in structure and properties of niobium pentoxide in the result of electrode processes under cathodic polarization (at the model structure of polycrystalline film), as well as the methods of amorphous electrochromic AOP development and ways of electrochromic processes optimization at such films
The Nature of Time - A 21st Century View
Get PDFThis article is a logical analysis of historical records and reaches conclusions that are original.
Prior to 1905 it was generally believed that the universe had always existed. The exact age of Earth was not known.
The luminiferous æther theory explained how light was able to propagate through empty space.
In 1930 Alfred Korzybski published his book “Science and Sanity”. In it he originated his aphorism —The Map is not the Territory.
Reality consists of physical reality — the territory— and observed reality — the map.
The Rossi-Hall experiment demonstrated that time dilation occurs physically and cannot be observed directly.
The universe came into existence when the big bang occurred.
When photons came into being, time came into being.
All mechanisms for measuring time experience time dilation.
The big bang caused major changes to science’s understanding of the nature of the universe.
The speed of a photon through space equals a Planck length divided by a Planck time.
We don’t really measure time, what we measure is the effect that time has on the instruments used to measure time.
Everything; in Relative Time is based on observers. If you remove all references to observers from either Special Relativity or Spacetime there is almost nothing left.
When the concepts of relative time were originated, no thought was given to the possibility that time might consist of both observed time and physical time.
Photons — and the resulting time — came into existence with the big bang
The movement of photons thru spacetime constitutes absolute time
Without events, nothing happens.
Every event has a frame of reference.
‘Now’ can occur in physical time and in observed time.
A physical event always results in a physical ‘now’.
Every event must have a frame of reference.
Objects that move through space experience time dilation but they do not observe it.
The observation of each observer is unique for that observer and need not be the same as either the actual event itself or the observation of another observer.
Each observer has his/her own observed ‘now’ which occurs in observer’s frame of reference.
The duration of an observation has no direct relationship to the duration of the event nor need it have the same duration as that of another observer.
Each observer has her/his own frame of reference.
Time dilation is an aspect of physical time, not of observed time.
Observers have no way of knowing that they are experiencing time dilation.
The Lorentz transformation factor ‘?’ is computed by dividing ‘v2’ which is a vector by ‘c2’ which is scalar. Both terms should be scalar.
Both ‘v’ and ‘c’ use clocks to determine their value and all clocks are subject to time dilation.
The Lorentz transaction is supposed to measure ‘?’ but ‘?’ is an element of the calculation
Multisource Evidence for Final State Hadrons in 3.7A Gev 16O–Nucleus Interactions
Get PDF In 3.7A GeV 16O interactions with emulsion nuclei, the shower particle multiplicity characteristics are investigated. Data are presented in terms of the number of emitted particles in both forward and backward angular zones. The dependence on the target size and emission direction is presented. The target separation of events depends on Glauber's multiple scattering theory approaches. A decay mechanism seems to be a characteristic of the backward production. This production may be during the de–excitation of the excited target nucleus, regarding the nuclear limiting fragmentation hypothesis. The forward emitted particle is due to a creation system. The target size is an effective parameter as well as the projectile size in this system, considering the geometrical concept regarded in the nuclear fireball concept. The data are simulated in the framework of the modified FRITIOF model. The multisource thermal model can predict source numbers responsible for particle production.  
Characterization of Thermally Evaporated CdSe1-XSX Thin Films for Solar Cells Applications
Get PDFBinary semiconductor CdSe and CdS thin films are widely used for optoelectronic devices and window materials. The formation of ternary CdSe1-xSx thin films improves the physical characteristics of the binary CdSe thin films. The importance of CdSe1-xSx thin film is the change of band gap when incorporating S into the CdSe. This change in energy gap recommends CdSe1-xSx thin film for photovoltaic and photoconductive cells applications. In this work, polycrystalline CdSe1-xSx thin films have been grown in terms of thermal evaporation technique. X-ray diffractometry has been used to determine the lattice parameters and the crystallite size of the CdSe1-xSx mixed crystals. The variation in lattice parameters with composition from x = 0 to x = 1 were linearly. The crystallite size varies parabolically with the change in composition. The energy gap, opt g E , values of CdSe1-xSx thin films were estimated in terms of first derivative of absorbance with respect to wavelength and found to be increased with the formation of the ternary compound Cd-Se-S and with increasing the S content as expense of Se. This wider energy gap of the prepared films, which permits extra light to reach the solar cell junction, was correlated with the change in the microstructure parameters of thin films
Neutron Activation Analysis of Some Building Material
Get PDFNeutron activation analysis (NAA), based on the comparator method, has the potential to fulfill the requirements of a primary ratio method as defined in 1998 by the Comité Consultatif pour la Quantité de Matière — Métrologie en Chimie (CCQM, Consultative Committee on Amount of Substance — Metrology in Chemistry Studies of Neutron Activation Analysis (NAA) have been carried out on different Egyptian building material samples. The technique of neutron activation analysis is based on the measurement of radiation released by the decay of radioactive nuclei formed by neutron irradiation of the material. The most suitable source of neutrons for such an application is usually a research reactor. The samples that can be analyzed with this method stem from a number of different fields, including medicine, nutrition, biology, chemistry, forensics, the environment and mining. Neutron activation analysis can be performed in a variety of ways. This depends on the element and the corresponding radiation levels to be measured, as well as on the nature and the extent of interference from other elements present in the sample. Most of the methods used are non-destructive, based on the detection of gamma radiation emitted by the irradiated material after or during the irradiation. Next to education and training, neutron activation analysis is the most widely used application of research reactors. Almost any reactor operating at 10-30 kilowatt of thermal power is capable of providing a sufficient neutron flux to irradiate samples for selective applications of this analysis technique. Another method of NAA by using two Am-Be isotopic neutron sources of activity 5 Ci were used in this investigation. The accomplished gamma rays were measured using 70 % HPGe spectrometer. This work demand to estimate the elements contained in cement products and its quality control. X-ray Fluorescence (XRF) measurements were done for confirming our results, and for determining the average neutron flux of 3.7× 103 n/cm2sec. The Natural radioactivities of these samples were measured before the analysis to know the background level of 40K, 238U and232Th nuclei. The results investigated that NAA agree with the results of XRF and the world range of the cement concentration of the essential elements Ca, Al, Na, Fe, Mn, V, Sr and Si
Nano Crystallites and Clustered Species in Modified Sodium Telluride Glasses
Get PDFThe structural properties, crystalline and clustering behavior of xNa2O·(1-x)TeO2 (15 £ x £ 65 mol% glasses have been investigated by FTIR spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM ). The experimental results have demonstrated that the basic structural units in telluride glasses change from highly strained TeO4 trigonal bipyramids to more regular TeO3 units containing non bridging oxygen atoms (NBO). The concentration of NBO atoms in telluride network increases with increasing? Na2O content. The present results suggest that (NBO) atoms in telluride glasses exist in their pure form in glasses of up to 35 mol% Na2O. But at higher Na2O concentrations, NBO atoms do not exist in their pure form; that is, the majority of NBO atoms are coordinated with high concentration from Na cations to form nano-crystalline clusters. The results based on X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calomerty (DSC) reveal the presence of two crystalline phases: ? TeO2 and Na2Te4O9 phases during the crystallization process of the prepared glass in the region < 50 mol% Na2O. But at higher Na2O concentrations, Na2Te2O5 and NaTeO3 crystalline clustered phase in the nono size scale are the dominant type. This means that NBO in TeO3 trigonal pyramids will interact with the excess of Na cation resulting in the three-dimensional network containing nano size clusters particularly in telluride glasses containing 50 and 65 mol% Na2O. An increase in Na2O concentration in Na2O-rich telluride network results in increasing Na coordination instead of breaking more tellurium–oxygen bonds
The Quantum World Is Astonishingly Similar to Our World: The Timing of Wave Function Collapse According to The Theory of Elementary Waves
Get PDFThis is one of a series of articles building a map of elementary waves, based on experimental data and quantum mathematics. Previous articles showed that elementary waves carry no energy. Particles follow them backwards. Why? Elementary rays consist of probability amplitudes, which influence particles because that is what probability amplitudes do. Elementary waves are that part of nature corresponding to quantum mathematics. Since these waves are the physical analogs of quantum equations, those equations provide a roadmap to the world of elementary waves: a map written in hieroglyphs. Quantum math is our Rosetta stone. The quantum world is far, far more similar to the world of everyday experience than quantum experts think. Waves are in a superposition. Particles are not. Wave function collapse does not occur when we measure something. It had occurred much earlier, when the object came into existence. This resolves insoluble problems that stumped John von Neumann. The smooth functioning of a Schrödinger equation abruptly collapses into one specific eigenstate when a gun is fired, not when the bullet hits the target. The bullet that caused World War I is an example. That bullet caused an abrupt collapse of the smooth probabilities of commerce and diplomacy