Leo J. Elders, S.V.D.
2014-12-01
Full Text Available Inspired with Jude P. Dougherty’s works in which he stresses the overruling importance of the classical, humanistic education and the central place and role of religion in the Western culture, the author presents Christopher Dawson’s analysis of the Western civilization and his demonstration of the central role of Christianity in it. The author traces the premises on which was based Dawson’s opinion that modern Western man might be absorbed by his technical inventions, to the point of losing his soul.
Bigravitons as dark matter and gravitational waves
Aoki, Katsuki
2016-01-01
We consider the possibility that the massive graviton is a viable candidate of dark matter in the context of bimetric gravity. We first derive the energy-momentum tensor of the massive graviton and show that it indeed behaves as that of dark matter fluid. We then discuss a production mechanism and the present abundance of massive gravitons as dark matter. Since the metric to which ordinary matter fields couple is a linear combination of the two mass eigenstates of bigravity, production of massive gravitons, i.e. the dark matter particles, is inevitably accompanied by generation of massless gravitons, i.e. the gravitational waves. Therefore, in this scenario some information about dark matter in our universe is encoded in gravitational waves. For instance, if LIGO detects gravitational waves generated by the preheating after inflation then the massive graviton with the mass of $\\sim 0.01$ GeV is a candidate of the dark matter.
Nonautonomous matter waves in a waveguide
Yan Zhenya [Key Laboratory of Mathematics Mechanization, Institute of Systems Science, AMSS, Chinese Academy of Sciences, Beijing 100190 (China); Zhang Xiaofei [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); College of Science, Honghe University, Mengzi 661100 (China); Liu, W. M. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)
2011-08-15
We present a physical model that describes the transport of Bose-Einstein-condensed atoms from a reservoir to a waveguide. By using the similarity and Moebius transformations, we study nonautonomous matter waves in Bose-Einstein condensates in the presence of an inhomogeneous source. Then, we find its various types of exact nonautonomous matter-wave solutions, including the W-shaped bright solitary waves, W-shaped and U-shaped dark solitary waves, periodic wave solutions, and rational solitary waves. The results show that these different types of matter-wave structures can be generated and effectively controlled by modulating the amplitude of the source. Our results may raise the possibility of some experiments and potential applications related to Bose-Einstein condensates in the presence of an inhomogeneous source.
The Higgs boson at the LHC - a voyage to the heart of matter | by Christophe GROJEAN | December 18
2012-01-01
Tuesday 18 December 2012 at 8.30 p.m. Globe of Science and Innovation Route de Meyrin, 1211 Geneva Lecture will be in French - Translation available in English No specialist knowledge required - Entrance free Limited number of seats - registration is essential Reservation: +41 22 767 76 76 The Sun has been warming our backs for several billion years now, and it’s all thanks to a handful of elementary particles and their mass. The Higgs boson is a particle that interacts with others, giving them mass. The long and painstaking search for this elusive particle finally bore fruit in July this year – but only one in 10 billion collisions in the LHC produces a Higgs boson. Worse still – no sooner is it produced than it vanishes again and is replaced by other, run-of-the-mill particles. You might ask: “what on earth can we learn from the discovery of a new particle?” Quite a lot, as it happens. It might explain why matter dominates antimatter in the Universe, o...
Beck, Martha Davis
2000-01-01
This interview with Christopher Paul Curtis, an award-winning author of novels for young readers, discusses combining elements of the author's own family heritage with American history; writing about race that appeals to black and white readers; the history of race relations; the use of humor; and thinking about the audience. (LRW)
Interview with Christoph Schwabe
Melanie Voigt
2010-03-01
Full Text Available I travelled to Gera, where Dr. Christoph Schwabe met me [...] It was a cold, windy day, and we sat in front of the fireplace and talked for over two hours about his way toward music therapy, the development of music therapy in the German Democratic Republic (GDR, different influences and experiences within that field before 1989 and the changes that have taken place since then.
Wave Dark Matter and Dwarf Spheroidal Galaxies
Parry, Alan R.
We explore a model of dark matter called wave dark matter (also known as scalar field dark matter and boson stars) which has recently been motivated by a new geometric perspective by Bray. Wave dark matter describes dark matter as a scalar field which satisfies the Einstein-Klein-Gordon equations. These equations rely on a fundamental constant Upsilon (also known as the "mass term'' of the Klein-Gordon equation). Specifically, in this dissertation, we study spherically symmetric wave dark matter and compare these results with observations of dwarf spheroidal galaxies as a first attempt to compare the implications of the theory of wave dark matter with actual observations of dark matter. This includes finding a first estimate of the fundamental constant Upsilon. In the introductory Chapter 1, we present some preliminary background material to define and motivate the study of wave dark matter and describe some of the properties of dwarf spheroidal galaxies. In Chapter 2, we present several different ways of describing a spherically symmetric spacetime and the resulting metrics. We then focus our discussion on an especially useful form of the metric of a spherically symmetric spacetime in polar-areal coordinates and its properties. In particular, we show how the metric component functions chosen are extremely compatible with notions in Newtonian mechanics. We also show the monotonicity of the Hawking mass in these coordinates. Finally, we discuss how these coordinates and the metric can be used to solve the spherically symmetric Einstein-Klein-Gordon equations. In Chapter 3, we explore spherically symmetric solutions to the Einstein-Klein-Gordon equations, the defining equations of wave dark matter, where the scalar field is of the form f(t, r) = eiotF(r) for some constant o ∈ R and complex-valued function F(r). We show that the corresponding metric is static if and only if F( r) = h(r)eia for some constant alpha ∈ R and real-valued function h(r). We describe the
Scalar Field (Wave) Dark Matter
Matos, T
2016-01-01
Recent high-quality observations of dwarf and low surface brightness (LSB) galaxies have shown that their dark matter (DM) halos prefer flat central density profiles. On the other hand the standard cold dark matter model simulations predict a more cuspy behavior. Feedback from star formation has been widely used to reconcile simulations with observations, this might be successful in field dwarf galaxies but its success in low mass galaxies remains uncertain. One model that have received much attention is the scalar field dark matter model. Here the dark matter is a self-interacting ultra light scalar field that forms a cosmological Bose-Einstein condensate, a mass of $10^{-22}$eV/c$^2$ is consistent with flat density profiles in the centers of dwarf spheroidal galaxies, reduces the abundance of small halos, might account for the rotation curves even to large radii in spiral galaxies and has an early galaxy formation. The next generation of telescopes will provide better constraints to the model that will help...
Multimode interferometer for guided matter waves.
Andersson, Erika; Calarco, Tommaso; Folman, Ron; Andersson, Mauritz; Hessmo, Björn; Schmiedmayer, Jörg
2002-03-11
Atoms can be trapped and guided with electromagnetic fields, using nanofabricated structures. We describe the fundamental features of an interferometer for guided matter waves, built of two combined Y-shaped beam splitters. We find that such a device is expected to exhibit high contrast fringes even in a multimode regime, analogous to a white light interferometer.
Matter-Wave Optics of Diatomic Molecules
2012-10-23
Lima , Peru (2010). S. Singh and P. Meystre, "Atomic probe Wigner tomography of a nanomechanical system," contributed paper, APS DAMOP Annual Meeting...Triangle Park , NC 27709-2211 15. SUBJECT TERMS matter-wave optics, ultracold molecules, polar molecules, quantum optomechanics, quantum-degenerate
Coordinate transformations and matter waves cloaking
Mohammadi, G.R. [Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791 (Iran, Islamic Republic of); Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Moghaddam, A.G. [Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Mohammadkhani, R., E-mail: rmkhani@znu.ac.ir [Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791 (Iran, Islamic Republic of)
2016-03-06
Transformation method provides an efficient tool to control wave propagation inside the materials. Using the coordinate transformation approach, we study invisibility cloaks with sphere, cylinder and ellipsoid structures for electronic waves propagation. The underlying physics behind this investigation is the fact that Schrödinger equation with position dependent mass tensor and potentials has a covariant form which follows the coordinate transformation. Using this technique we obtain the exact spatial form of the mass tensor and potentials for a variety of cloaks with different shapes. - Highlights: • Invisibility cloaks for matter waves with three different geometries. • Exact analytical form of the effective mass tensor and potential. • Analogy between cloaking for quantum mechanical waves with classical electromagnetic waves. • Possible experimental realization in engineered semiconducting structures.
Fredrik Lindstrand
2008-03-01
Full Text Available In addition to the articles published in Designs for Learning, each issue will also include an interview with a person who is prominent within any of the fields that relate to the themes of the journal. The readers of this issue have already made acquaintance with professor Christoph Wulf through his article on mimetic learning. In the interview that follows we hope to give some further insights regarding interests and influences that form a background to his theoretical work. A further contextualisation of his article, so to speak.
Ghost Imaging with Matter Waves
Khakimov, Roman; Henson, Bryce; Shin, David; Hodgman, Sean; Dall, Robert; Baldwin, Kenneth; Truscott, Andrew
2016-05-01
We demonstrate, for the first time, high resolution ghost imaging of a macroscopic object using atoms. Ghost imaging is a novel technique in which the image emerges from cross-correlation of particles (usually photons)in two separate beams. One beam is detected with a single-pixel (bucket detector) after passing through the object, while the other beam does not interact with the object and is registered with high spatial resolution. Neither detector can reconstruct the image independently. In our experiment, the two beams are formed by correlated pairs of ultracold metastable helium atoms originating from thecollision of two Bose-Einstein Condensates. After s-wave scattering the atoms form a spherical shell of strongly correlated pairs with opposite momenta. We extend this technique with more than a10-foldincrease in the number of correlated pairs available for eachsingle experiment run, by using higher-order Bragg scattering in the Kapitza-Dirac regime, with multiple shells generated from different diffraction orders. Using single-atom detection, we create ghost images of a target maskwith a resolution given by the width of the cross-corrrelation function of atomic momenta. Future extensions could include ghost interference and EPR tests.
Christopher Bollyn : kaksiktornid lasti õhku / Christopher Bollyn ; interv. Krister Paris
Bollyn, Christopher
2007-01-01
Vabakutseline ajakirjanik Christopher Bollyn vastab küsimustele 11. septembril 2001 USA-s aset leidnud rünnaku kohta ning leiab, et see oli vandenõuteooria. Kommenteerib Olga Slov. Vt. samas: Ametlik tõde
Schroedinger's Wave Structure of Matter (WSM)
Wolff, Milo; Haselhurst, Geoff
2009-10-01
The puzzling electron is due to the belief that it is a discrete particle. Einstein deduced this structure was impossible since Nature does not allow the discrete particle. Clifford (1876) rejected discrete matter and suggested structures in `space'. Schroedinger, (1937) also eliminated discrete particles writing: What we observe as material bodies and forces are nothing but shapes and variations in the structure of space. Particles are just schaumkommen (appearances). He rejected wave-particle duality. Schroedinger's concept was developed by Milo Wolff and Geoff Haselhurst (SpaceAndMotion.com) using the Scalar Wave Equation to find spherical wave solutions in a 3D quantum space. This WSM, the origin of all the Natural Laws, contains all the electron's properties including the Schroedinger Equation. The origin of Newton's Law F=ma is no longer a puzzle; It originates from Mach's principle of inertia (1883) that depends on the space medium and the WSM. Carver Mead (1999) at CalTech used the WSM to design Intel micro-chips correcting errors of Maxwell's magnetic Equations. Applications of the WSM also describe matter at molecular dimensions: alloys, catalysts, biology and medicine, molecular computers and memories. See ``Schroedinger's Universe'' - at Amazon.com
Avoided-level-crossing spectroscopy with dressed matter waves.
Eckardt, André; Holthaus, Martin
2008-12-12
We devise a method for probing resonances of macroscopic matter waves in shaken optical lattices by monitoring their response to slow parameter changes, and show that such resonances can be disabled by particular choices of the driving amplitude. The theoretical analysis of this scheme reveals far-reaching analogies between dressed atoms and time periodically forced matter waves.
Sims, Christopher Albert (born 1942)
Boumans, Marcel
2015-01-01
Christopher Sims is one of the leaders in time-series econometrics and empirical macroeconomics and is well known for introducing the VAR approach to econometrics and macroeconomic modelling. Sims’ main contribution to empirical macroeconomics was to show how macro-econometric modeling should be rev
Christopher Benfey's Flight of Fancy
Klein, Julia M.
2008-01-01
This article profiles Christopher Benfey, 53--an art critic for Slate, a poet, and a prolific literary essayist for such venues as "The New York Times Book Review, The New Republic," and "The New York Review of Books." His latest book, "A Summer of Hummingbirds: Love, Art, and Scandal in the Intersecting Worlds of Emily Dickinson, Mark Twain,…
Sims, Christopher Albert (born 1942)
Boumans, Marcel
2015-01-01
Christopher Sims is one of the leaders in time-series econometrics and empirical macroeconomics and is well known for introducing the VAR approach to econometrics and macroeconomic modelling. Sims’ main contribution to empirical macroeconomics was to show how macro-econometric modeling should be
Detecting dark matter waves with precision measurement tools
Derevianko, Andrei
2016-01-01
Virialized Ultra-Light Fields (VULFs) while being viable cold dark matter candidates can also solve the standard model hierarchy problem. Direct searches for VULFs due to their non-particle nature require low-energy precision measurement tools. Here we consider scalar VULF candidates. While the previous proposals have focused on detecting coherent oscillations of the measured signals at the VULF Compton frequencies at the device location, here we point out that VULFs also have a distinct spatial signature, forming dark matter waves. Thereby the discovery reach can be improved by using distributed networks of precision measurement tools. We find the expected dark-matter wave signal by deriving spatio-temporal two-point VULF correlation function. Based on the developed formalism for coherence properties of dark-matter fields, we propose several experiments for dark matter wave detection. In the most basic version, the modifications to already running experiments are minor and only require GPS-assisted time-stam...
Christopher Lasch and Prairie Populism
Lauck, Jon K.
2012-01-01
Christopher Lasch was born in Omaha in 1932. By the end of his life, cut short at age sixty-one, he had become one of the most famous intellectuals in the world. During his life of active writing from the time of the early Cold War until the fall of the Soviet Union, Lasch's distinctive voice pierced through the din of the nation's noisy political…
Coherent matter wave optics on an atom chip
Krüger, Peter; Hofferberth, S.; Schumm, Thorsten
2006-01-01
Coherent manipulation of matter waves in microscopic trapping potentials facilitates both fundamental and technological applications. Here we focus on experiments with a microscopic integrated interferometer that demonstrate coherent operation on an atom chip.......Coherent manipulation of matter waves in microscopic trapping potentials facilitates both fundamental and technological applications. Here we focus on experiments with a microscopic integrated interferometer that demonstrate coherent operation on an atom chip....
Shock wave compression of condensed matter a primer
Forbes, Jerry W
2012-01-01
This book introduces the core concepts of the shock wave physics of condensed matter, taking a continuum mechanics approach to examine liquids and isotropic solids. The text primarily focuses on one-dimensional uniaxial compression in order to show the key features of condensed matter’s response to shock wave loading. The first four chapters are specifically designed to quickly familiarize physical scientists and engineers with how shock waves interact with other shock waves or material boundaries, as well as to allow readers to better understand shock wave literature, use basic data analysis techniques, and design simple 1-D shock wave experiments. This is achieved by first presenting the steady one-dimensional strain conservation laws using shock wave impedance matching, which insures conservation of mass, momentum and energy. Here, the initial emphasis is on the meaning of shock wave and mass velocities in a laboratory coordinate system. An overview of basic experimental techniques for measuring pressure...
Path integrals, matter waves, and the double slit
Jones, Eric R.; Bach, Roger A.; Batelaan, Herman
2015-11-01
Basic explanations of the double slit diffraction phenomenon include a description of waves that emanate from two slits and interfere. The locations of the interference minima and maxima are determined by the phase difference of the waves. An optical wave, which has a wavelength λ and propagates a distance L, accumulates a phase of 2π L/λ . A matter wave, also having wavelength λ that propagates the same distance L, accumulates a phase of π L/λ , which is a factor of two different from the optical case. Nevertheless, in most situations, the phase difference, {{Δ }}\\varphi , for interfering matter waves that propagate distances that differ by {{Δ }}L, is approximately 2π {{Δ }}L/λ , which is the same value computed in the optical case. The difference between the matter and optical case hinders conceptual explanations of diffraction from two slits based on the matter-optics analogy. In the following article we provide a path integral description for matter waves with a focus on conceptual explanation. A thought experiment is provided to illustrate the validity range of the approximation {{Δ }}\\varphi ≈ 2π {{Δ }}L/λ .
Multiple scattering induced negative refraction of matter waves
Pinsker, Florian
2016-01-01
Starting from fundamental multiple scattering theory it is shown that negative refraction indices are feasible for matter waves passing a well-defined ensemble of scatterers. A simple approach to this topic is presented and explicit examples for systems of scatterers in 1D and 3D are stated that imply negative refraction for a generic incoming quantum wave packet. Essential features of the effective scattering field, densities and frequency spectrum of scatterers are considered. Additionally it is shown that negative refraction indices allow perfect transmission of the wave passing the ensemble of scatterers. Finally the concept of the superlens is discussed, since it is based on negative refraction and can be extended to matter waves utilizing the observations presented in this paper which thus paves the way to ‘untouchable’ quantum systems in analogy to cloaking devices for electromagnetic waves. PMID:26857266
Photofragmentation Beam Splitters for Matter-Wave Interferometry
Dörre, Nadine; Rodewald, Jonas; Geyer, Philipp; von Issendorff, Bernd; Haslinger, Philipp; Arndt, Markus
2014-12-01
Extending the range of quantum interferometry to a wider class of composite nanoparticles requires new tools to diffract matter waves. Recently, pulsed photoionization light gratings have demonstrated their suitability for high mass matter-wave physics. Here, we extend quantum interference experiments to a new class of particles by introducing photofragmentation beam splitters into time-domain matter-wave interferometry. We present data that demonstrate this coherent beam splitting mechanism with clusters of hexafluorobenzene and we show single-photon depletion gratings based both on fragmentation and ionization for clusters of vanillin. We propose that photofragmentation gratings can act on a large set of van der Waals clusters and biomolecules which are thermally unstable and often resilient to single-photon ionization.
Photofragmentation beam splitters for matter-wave interferometry
Dörre, Nadine; Geyer, Philipp; von Issendorff, Bernd; Haslinger, Philipp; Arndt, Markus
2014-01-01
Extending the range of quantum interferometry to a wider class of composite nanoparticles requires new tools to diffract matter-waves. Recently, pulsed photoionization light gratings have demonstrated their suitability for high mass matter-wave physics. Here we extend quantum interference experiments to a new class of particles by introducing photofragmentation beam splitters into time-domain matter-wave interferometry. Photofragmentation gratings can act on objects as different as van der Waals clusters and biomolecules which are thermally unstable and often resilient to single-photon ionization. We present data that demonstrate this coherent beam splitting mechanism with clusters of hexafluorobenzene and we show single-photon depletion gratings based both on fragmentation and ionization for clusters of vanillin.
Coordinate transformations and matter waves cloaking
Mohammadi, G. R.; Moghaddam, A. G.; Mohammadkhani, R.
2016-03-01
Transformation method provides an efficient tool to control wave propagation inside the materials. Using the coordinate transformation approach, we study invisibility cloaks with sphere, cylinder and ellipsoid structures for electronic waves propagation. The underlying physics behind this investigation is the fact that Schrödinger equation with position dependent mass tensor and potentials has a covariant form which follows the coordinate transformation. Using this technique we obtain the exact spatial form of the mass tensor and potentials for a variety of cloaks with different shapes.
Excitation of knotted vortex lines in matter waves
Maucher, F.; Gardiner, S. A.; Hughes, I. G.
2016-06-01
We study the creation of knotted ultracold matter waves in Bose-Einstein condensates via coherent two-photon Raman transitions with a Λ level configuration. The Raman transition allows an indirect transfer of atoms from the internal state | a> to the target state | b> via an excited state | e> , that would be otherwise dipole-forbidden. This setup enables us to imprint three-dimensional knotted vortex lines embedded in the probe field to the density in the target state. We elaborate on experimental feasibility as well as on subsequent dynamics of the matter wave.
Matter-wave bright solitons in effective bichromatic lattice potentials
Golam Ali Sekh
2013-08-01
Matter-wave bright solitons in bichromatic lattice potentials are considered and their dynamics for different lattice environments are studied. Bichromatic potentials are created from superpositions of (i) two linear optical lattices and (ii) a linear and a nonlinear optical lattice. Effective potentials are found for the solitons in both bichromatic lattices and a comparative study is done on the dynamics of solitons with respect to the effective potentials. The effects of dispersion on solitons in bichromatic lattices are studied and it is found that the dispersive spreading can be minimized by appropriate combinations of lattice and interaction parameters. Stability of nondispersive matter-wave solitons is checked from phase portrait analysis.
Quantum interference of molecules -- probing the wave nature of matter
Venugopalan, Anu
2012-01-01
The double slit interference experiment has been famously described by Richard Feynman as containing the "only mystery of quantum mechanics". The history of quantum mechanics is intimately linked with the discovery of the dual nature of matter and radiation. While the double slit experiment for light is easily undertsood in terms of its wave nature, the very same experiment for particles like the electron is somewhat more difficult to comprehend. By the 1920s it was firmly established that electrons have a wave nature. However, for a very long time, most discussions pertaining to interference experiments for particles were merely gedanken experiments. It took almost six decades after the establishment of its wave nature to carry out a 'double slit interference' experiment for electrons. This set the stage for interference experiments with larger particles. In the last decade there has been spectacular progress in matter-wave interefernce experiments. Today, molecules with over a hundred atoms can be made to i...
Christopher Clavius astronomer and mathematician
Sigismondi, Costantino
2012-01-01
The Jesuit scientist Christopher Clavius (1538-1612) has been the most influential teacher of the renaissance. His contributions to algebra, geometry, astronomy and cartography are enormous. He paved the way, with his texts and his teaching for 40 years in the the Collegio Romano, to the development of these sciences and their fruitful spread all around the World, along the commercial paths of Portugal, which become also the missionary paths for the Jesuits. The books of Clavius were translated into Chinese, by one of his students Matteo Ricci "Li Madou" (1562-1610), and his influence for the development of science in China was crucial. The Jesuits become skilled astronomers, cartographers and mathematicians thanks to the example and the impulse given by Clavius. This success was possible also thanks to the contribution of Clavius in the definition of the Ratio Studiorum, the program of studies, in the Jesuit colleges, so influential for the whole history of modern Europe and all western World.
Wave packet dynamics of the matter wave field of a Bose-Einstein condensate
Sudheesh, C; Lakshmibala, S
2004-01-01
We show in the framework of a tractable model that revivals and fractional revivals of wave packets afford clear signatures of the extent of departure from coherence and from Poisson statistics of the matter wave field in a Bose-Einstein condensate, or of a suitably chosen initial state of the radiation field propagating in a Kerr-like medium.
Weak Nonlinear Matter Waves in a Trapped Spin-1 Condensates
CAI Hong-Qiang; YANG Shu-Rong; XUE Ju-Kui
2011-01-01
The dynamics of the weak nonlinear matter solitary waves in a spin-1 condensates with harmonic external potential are investigated analytically by a perturbation method. It is shown that, in the small amplitude limit, the dynamics of the solitary waves are governed by a variable-coefficient Korteweg-de Vries (KdV) equation. The reduction to the (KdV) equation may be useful to understand the dynamics of nonlinear matter waves in spinor BEGs. The analytical expressions for the evolution of soliton show that the small-amplitude vector solitons of the mixed types perform harmonic oscillations in the presence of the trap. Furthermore, the emitted radiation profiles and the soliton oscillation freauencv are also obtained.
Modal decomposition of a propagating matter wave via electron ptychography
Cao, S.; Kok, P.; Li, P.; Maiden, A. M.; Rodenburg, J. M.
2016-12-01
We employ ptychography, a phase-retrieval imaging technique, to show experimentally that a partially coherent high-energy matter (electron) wave emanating from an extended source can be decomposed into a set of mutually independent modes of minimal rank. Partial coherence significantly determines the optical transfer properties of an electron microscope and so there has been much work on this subject. However, previous studies have employed forms of interferometry to determine spatial coherence between discrete points in the wave field. Here we use the density matrix to derive a formal quantum mechanical description of electron ptychography and use it to measure a full description of the spatial coherence of a propagating matter wave field, at least within the fundamental uncertainties of the measurements we can obtain.
Black Hole Window into p-Wave Dark Matter Annihilation.
Shelton, Jessie; Shapiro, Stuart L; Fields, Brian D
2015-12-01
We present a new method to measure or constrain p-wave-suppressed cross sections for dark matter (DM) annihilations inside the steep density spikes induced by supermassive black holes. We demonstrate that the high DM densities, together with the increased velocity dispersion, within such spikes combine to make thermal p-wave annihilation cross sections potentially visible in γ-ray observations of the Galactic center (GC). The resulting DM signal is a bright central point source with emission originating from DM annihilations in the absence of a detectable spatially extended signal from the halo. We define two simple reference theories of DM with a thermal p-wave annihilation cross section and establish new limits on the combined particle and astrophysical parameter space of these models, demonstrating that Fermi Large Area Telescope is currently sensitive to thermal p-wave DM over a wide range of possible scenarios for the DM distribution in the GC.
Interview with Christophe Grojean and Chiara Mariotti
Bennett, Sophia Elizabeth
2015-01-01
Christophe Grojean - Theoretical physicist at the DESY research centre in Germany. Chiara Mariotti - Experimental physicist at the italian institute INFN Turin working on the CMS experiment at the LHC.
Selective Sommerfeld Enhancement of p-wave Dark Matter Annihilation
Das, Anirban
2016-01-01
We point out a mechanism for selective Sommerfeld enhancement (suppression) of odd (even) partial waves of dark matter co/annihilation. Using this, the usually velocity-suppressed p-wave annihilation can dominate the annihilation signals in the present Universe. The selection mechanism is a manifestation of an exchange symmetry, and generic for DM with off-diagonal long-range interactions. As a consequence, the relic and late-time annihilation rates are parametrically different and a distinctive phenomenology, with large but strongly velocity-dependent annihilation rates, is predicted.
Globalization and Christopher Columbus in the Americas
Bartosik-Vélez, Elise
2006-01-01
In "Globalization and Christopher Columbus in the Americas," Elise Bartosik-Vélez considers the responses of scholars working in colonial and early modern studies to recent exponential increases in the transnationalization of capital and the resulting changes in the role of the nation-state. The case of Christopher Columbus and his appropriation by US-American nationalists during the early modern period is particularly instructive with regard to this discussion because Columbus exemplifies no...
Influence of conformational molecular dynamics on matter wave interferometry
Gring, Michael; Eibenberger, Sandra; Nimmrichter, Stefan; Berrada, Tarik; Arndt, Markus; Ulbricht, Hendrik; Hornberger, Klaus; Müri, Marcel; Mayor, Marcel; Böckmann, Marcus; Doltsinis, Nikos
2014-01-01
We investigate the influence of thermally activated internal molecular dynamics on the phase shifts of matter waves inside a molecule interferometer. While de Broglie physics generally describes only the center-of-mass motion of a quantum object, our experiment demonstrates that the translational quantum phase is sensitive to dynamic conformational state changes inside the diffracted molecules. The structural flexibility of tailor-made hot organic particles is sufficient to admit a mixture of strongly fluctuating dipole moments. These modify the electric susceptibility and through this the quantum interference pattern in the presence of an external electric field. Detailed molecular dynamics simulations combined with density functional theory allow us to quantify the time-dependent structural reconfigurations and to predict the ensemble-averaged square of the dipole moment which is found to be in good agreement with the interferometric result. The experiment thus opens a new perspective on matter wave interfe...
Decoherence of matter waves by thermal emission of radiation
Hackermüller, L; Brezger, B; Zeilinger, Anton; Arndt, M; Hackermueller, Lucia; Hornberger, Klaus; Brezger, Bjoern; Zeilinger, Anton; Arndt, Markus
2004-01-01
Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external photons or molecules, and by investigations using coherent photon states, trapped ions and electron interferometers. Large molecules are particularly suitable for the investigation of the quantum-classical transition because they can store much energy in numerous internal degrees of freedom; the internal energy can be converted into thermal radiation and thus induce decoherence. Here we report matter wave interferometer experiments in which C70 molecules lose their quantum behaviour by thermal emission of radiation. We find...
Gravitational Waves From SU(N) Glueball Dark Matter
Soni, Amarjit
2016-01-01
A hidden sector with pure non-abelian gauge symmetry is an elegant and just about the simplest model of dark matter. In this model the dark matter candidate is the lightest bound state made of the confined gauge fields, the dark glueball. In spite of its simplicity, the model has been shown to have several interesting non-standard implications in cosmology. In this work, we explore the gravitational waves from binary boson stars made of self-gravitating dark glueball fields as a natural and important consequence. We derive the dark SU($N$) star mass and radius as functions of the only two fundamental parameters in the model, the glueball mass $m$ and the number of colors $N$, and identify the regions that could be probed by the LIGO and future gravitational wave observatories.
Detecting inertial effects with airborne matter-wave interferometry
Geiger, Remi; Stern, Guillaume; Zahzam, Nassim; Cheinet, Patrick; Battelier, Baptiste; Villing, André; Moron, Frédéric; Lours, Michel; Bidel, Yannick; Bresson, Alexandre; Landragin, Arnaud; Bouyer, Philippe
2011-01-01
Inertial sensors relying on atom interferometry offer a breakthrough advance in a variety of applications, such as inertial navigation, gravimetry or ground- and space-based tests of fundamental physics. These instruments require a quiet environment to reach their performance and using them outside the laboratory remains a challenge. Here we report the first operation of an airborne matter-wave accelerometer set up aboard a 0g plane and operating during the standard gravity (1g) and microgravity (0g) phases of the flight. At 1g, the sensor can detect inertial effects more than 300 times weaker than the typical acceleration fluctuations of the aircraft. We describe the improvement of the interferometer sensitivity in 0g, which reaches 2 x 10-4 ms-2 / \\surdHz with our current setup. We finally discuss the extension of our method to airborne and spaceborne tests of the Universality of free fall with matter waves.
Detecting inertial effects with airborne matter-wave interferometry.
Geiger, R; Ménoret, V; Stern, G; Zahzam, N; Cheinet, P; Battelier, B; Villing, A; Moron, F; Lours, M; Bidel, Y; Bresson, A; Landragin, A; Bouyer, P
2011-09-20
Inertial sensors relying on atom interferometry offer a breakthrough advance in a variety of applications, such as inertial navigation, gravimetry or ground- and space-based tests of fundamental physics. These instruments require a quiet environment to reach their performance and using them outside the laboratory remains a challenge. Here we report the first operation of an airborne matter-wave accelerometer set up aboard a 0g plane and operating during the standard gravity (1g) and microgravity (0g) phases of the flight. At 1g, the sensor can detect inertial effects more than 300 times weaker than the typical acceleration fluctuations of the aircraft. We describe the improvement of the interferometer sensitivity in 0g, which reaches 2 x 10-4 ms-2 / √Hz with our current setup. We finally discuss the extension of our method to airborne and spaceborne tests of the Universality of free fall with matter waves.
Decoherence of matter waves by thermal emission of radiation
2004-01-01
Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external ph...
Wave functions in SUSY cosmological models with matter
Ortiz, C. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico); Rosales, J.J. [Facultad de Ingenieria Mecanica Electrica y Electronica, Universidad de Guanajuato, Prolongacion Tampico 912, Bellavista, Salamanca, Guanajuato (Mexico); Socorro, J. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico)]. E-mail: socorro@fisica.ugto.mx; Torres, J. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico); Tkach, V.I. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico)
2005-06-06
In this work we consider the n=2 supersymmetric superfield approach for the FRW cosmological model and the corresponding term of matter content, perfect fluid with barotropic state equation p={gamma}{rho}. We are able to obtain a normalizable wave function (at zero energy) of the universe. Besides, the mass parameter spectrum is found for the closed FRW case in the Schrodinger picture, being similar to those obtained by other methods, using a black hole system.
New avenues for matter-wave-enhanced spectroscopy
Rodewald, Jonas; Haslinger, Philipp; Dörre, Nadine; Stickler, Benjamin A.; Shayeghi, Armin; Hornberger, Klaus; Arndt, Markus
2017-01-01
We present matter-wave interferometry as a tool to advance spectroscopy for a wide class of nanoparticles, clusters and molecules. The high sensitivity of de Broglie interference fringes to external perturbations enables measurements in the limit of an individual particle absorbing only a single photon on average, or even no photon at all. The method allows one to extract structural and electronic information from the loss of the interference contrast. It is minimally invasive and works even for dilute ensembles.
Towards a matter wave interferometer on a sounding rocket
van Zoest, Tim; Peters, Achim; Ahlers, Holger; Wicht, Andreas; Vogel, Anika; Wenzlawski, Anderas; Deutsch, Christian; Kajari, Endre; Gaaloul, Naceur; Dittus, Hansjürg; Hartwig, Jonas; Herr, Waldemar; Herrmann, Sven; Reichel, Jakob; Bongs, Kai; Koenemann, Thorben; Laemmerzahl, Claus; Lewoczko-Adamczyk, Wojtek; Schiemangk, Max; Müntinga, Hauke; Meyer, Nadine; Rasel, Ernst Maria; Walser, Reinhold; Resch, Andreas; Rode, Christina; Seidel, Stephan; Sengstock, Klaus; Singh, Yeshpal; Schleich, Wolfgang; Ertmer, Wolfgang; Rosenbusch, Peter; Wilken, Tobias; Goeklue, Ertan
Applications of coherent matter waves are high resolution interferometers for measuring inertial and gravitational forces as well as testing fundamental physics, for which they may serve as a laser like source with mesoscopic quantum features. Out of possible applications, the test of the principle of equivalence in the quantum domain is selected as a target with the highest scientific interest on timescales of a microgravity experiment at the ISS or on a free flyer (ATV, FOTON or other satellites). The QUANTUS project demonstrated the technological feasibil-ity of coherent matter waves in microgravity. As a next step, the consortium will prepare and procure a sounding rocket mission to demonstrate technologies for matter wave interferome-try based on the broad experience of former developments with experiments in the droptower. Therefore, the experiment has to withstand strong requirements concerning environmental con-ditions (Temperature, shock, environmental pressure, etc.) and needs to be designed to fit in a 600 l volume (diameter 35 cm, length 160 cm). It is considered as an important step towards the technology required for the ISS and other platforms. These experiments will give further insights on the potential of inertial sensors based on atom interferometers and the technology is for example of interest for applications in earth observation and geodesy. They could replace classical techniques relying on test masses and promise a further improvement in the accuracy of such devices.
Peptides and proteins in matter wave interferometry: Challenges and prospects
Sezer, Ugur; Geyer, Philipp; Mairhofer, Lukas; Brand, Christian; Doerre, Nadine; Rodewald, Jonas; Schaetti, Jonas; Koehler, Valentin; Mayor, Marcel; Arndt, Markus
2016-05-01
Recent developments in matter wave physics suggest that quantum interferometry with biologically relevant nanomaterials is becoming feasible for amino acids, peptides, proteins and RNA/DNA strands. Quantum interference of biomolecules is interesting as it can mimic Schrödinger's cat states with molecules of high mass, elevated temperature and biological functionality. Additionally, the high internal complexity can give rise to a rich variety of couplings to the environment and new handles for quantitative tests of quantum decoherence. Finally, matter wave interferometers are highly sensitive force sensors and pave the way for quantum-assisted measurements of biomolecular properties in interaction with tailored or biomimetic environments. Recent interferometer concepts such as the Kapitza-Dirac-Talbot-Lau interferometer (KDTLI) or the Optical Time-domain Matter Wave interferometer (OTIMA) have already proven their potential for quantum optics in the mass range beyond 10000 amu and for metrology. Here we show our advances in quantum interferometry with vitamins and peptides and discuss methods of realizing cold, intense and sufficiently slow beams of synthetically tailored or hydrated polypeptides with promising properties for a new generation of quantum optics.
Transverse multipolar light-matter couplings in evanescent waves
Fernandez-Corbaton, Ivan; Bonod, Nicolas; Rockstuhl, Carsten
2016-01-01
We present an approach to study the interaction between matter and evanescent fields. The approach is based on the decomposition of evanescent plane waves into multipoles of well-defined angular momentum transverse to both decay and propagation directions. We use the approach to identify the origin of the recently observed directional coupling of emitters into guided modes, and of the opposite Zeeman state excitation of atoms near a fiber. We explain how to rigorously quantify both effects, and show that the directionality and the difference in excitation rates grow exponentially with the multipolar order of the light-matter interaction. We also use the approach to study and maximize the transverse torque exerted by an evanescent plane wave onto a given spherical absorbing particle. The maximum occurs at the quadrupolar order of the particle, and for a particular polarization of the plane wave. All the obtained physical insights can be traced back to the two main features of the decomposition of evanescent pl...
Discrete Wave-Packet Representation in Nuclear Matter Calculations
Müther, H; Kukulin, V I; Pomerantsev, V N
2016-01-01
The Lippmann-Schwinger equation for the nucleon-nucleon $t$-matrix as well as the corresponding Bethe-Goldstone equation to determine the Brueckner reaction matrix in nuclear matter are reformulated in terms of the resolvents for the total two-nucleon Hamiltonians defined in free space and in medium correspondingly. This allows to find solutions at many energies simultaneously by using the respective Hamiltonian matrix diagonalization in the stationary wave packet basis. Among other important advantages, this approach simplifies greatly the whole computation procedures both for coupled-channel $t$-matrix and the Brueckner reaction matrix. Therefore this principally novel scheme is expected to be especially useful for self-consistent nuclear matter calculations because it allows to accelerate in a high degree single-particle potential iterations. Furthermore the method provides direct access to the properties of possible two-nucleon bound states in the nuclear medium. The comparison between reaction matrices f...
Evanescent light-matter Interactions in Atomic Cladding Wave Guides
Stern, Liron; Goykhman, Ilya; Levy, Uriel
2012-01-01
Alkali vapors, and in particular rubidium, are being used extensively in several important fields of research such as slow and stored light non-linear optics3 and quantum computation. Additionally, the technology of alkali vapors plays a major role in realizing myriad industrial applications including for example atomic clocks magentometers8 and optical frequency stabilization. Lately, there is a growing effort towards miniaturizing traditional centimeter-size alkali vapor cells. Owing to the significant reduction in device dimensions, light matter interactions are greatly enhanced, enabling new functionalities due to the low power threshold needed for non-linear interactions. Here, taking advantage of the mature Complimentary Metal-Oxide-Semiconductor (CMOS) compatible platform of silicon photonics, we construct an efficient and flexible platform for tailored light vapor interactions on a chip. Specifically, we demonstrate light matter interactions in an atomic cladding wave guide (ACWG), consisting of CMOS ...
Into the lair: gravitational-wave signatures of dark matter
Macedo, Caio F B; Cardoso, Vitor; Crispino, Luis C B
2013-01-01
The nature and properties of dark matter (DM) are both outstanding issues in physics. The universal character of gravity implies that self-gravitating compact DM configurations are not only possible, but likely to be spread throughout the universe. The astrophysical signature of these objects may be used to probe fundamental particle physics, or even to provide an alternative description of compact objects in active galactic nuclei. Here we discuss the most promising dissection tool of these configurations: the inspiral of a compact stellar-size object and consequent gravitational-wave emission. The inward motion of this "test probe" encodes unique information about the nature of the central, supermassive DM configuration. When the probe travels through some compact DM profile we show that, within a Newtonian approximation, the quasi-adiabatic evolution of the inspiral is mainly driven by DM accretion into the small compact object and by dynamical friction, rather than by gravitational-wave radiation-reaction...
Decoherence of matter waves by thermal emission of radiation.
Hackermüller, Lucia; Hornberger, Klaus; Brezger, Björn; Zeilinger, Anton; Arndt, Markus
2004-02-19
Emergent quantum technologies have led to increasing interest in decoherence--the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external photons or molecules, and by investigations using coherent photon states, trapped ions and electron interferometers. Large molecules are particularly suitable for the investigation of the quantum-classical transition because they can store much energy in numerous internal degrees of freedom; the internal energy can be converted into thermal radiation and thus induce decoherence. Here we report matter wave interferometer experiments in which C70 molecules lose their quantum behaviour by thermal emission of radiation. We find good quantitative agreement between our experimental observations and microscopic decoherence theory. Decoherence by emission of thermal radiation is a general mechanism that should be relevant to all macroscopic bodies.
Coherent transport of matter waves in disordered optical potentials
Kuhn, Robert
2007-07-01
The development of modern techniques for the cooling and the manipulation of atoms in recent years, and the possibility to create Bose-Einstein condensates and degenerate Fermi gases and to load them into regular optical lattices or disordered optical potentials, has evoked new interest for the disorder-induced localization of ultra-cold atoms. This work studies the transport properties of matter waves in disordered optical potentials, which are also known as speckle potentials. The effect of correlated disorder on localization is first studied numerically in the framework of the Anderson model. The relevant transport parameters in the configuration average over many different realizations of the speckle potential are then determined analytically, using self-consistent diagrammatic perturbation techniques. This allows to make predictions for a possible experimental observation of coherent transport phenomena for cold atoms in speckle potentials. Of particular importance are the spatial correlations of the speckle fluctuations, which are responsible for the anisotropic character of the single scattering processes in the effective medium. Coherent multiple scattering leads to quantum interference effects, which entail a renormalization of the diffusion constant as compared to the classical description. This so-called weak localization of matter waves is studied as the underlying mechanism for the disorder-driven transition to the Anderson-localization regime, explicitly taking into account the correlations of the speckle fluctuations. (orig.)
The world in eighteen lessons: Christopher Williams
Berrebi, S.
2011-01-01
Conceptual photographer Christopher Williams is a real artist's artist. Ever since he moved to Germany, his measured work, which both reveres and examines the art of photography, has more and more easily found its way into European art institutes, such as this spring at Museum Dhondt-Dhaenens in Deu
Leilei Jia
2014-01-01
Full Text Available By using the bifurcation theory of dynamical systems, we present the exact representation and topological classification of coherent matter waves in Bose-Einstein condensates (BECs, such as solitary waves and modulate amplitude waves (MAWs. The existence and multiplicity of such waves are determined by the parameter regions selected. The results show that the characteristic of coherent matter waves can be determined by the “angular momentum” in attractive BECs while for repulsive BECs; the waves of the coherent form are all MAWs. All exact explicit parametric representations of the above waves are exhibited and numerical simulations support the result.
Discrete wave-packet representation in nuclear matter calculations
Müther, H.; Rubtsova, O. A.; Kukulin, V. I.; Pomerantsev, V. N.
2016-08-01
The Lippmann-Schwinger equation for the nucleon-nucleon t matrix as well as the corresponding Bethe-Goldstone equation to determine the Brueckner reaction matrix in nuclear matter are reformulated in terms of the resolvents for the total two-nucleon Hamiltonians defined in free space and in medium correspondingly. This allows one to find solutions at many energies simultaneously by using the respective Hamiltonian matrix diagonalization in the stationary wave-packet basis. Among other important advantages, this approach simplifies greatly the whole computation procedures both for the coupled-channel t matrix and the Brueckner reaction matrix. Therefore this principally novel scheme is expected to be especially useful for self-consistent nuclear matter calculations because it allows one to accelerate in a high degree single-particle potential iterations. Furthermore the method provides direct access to the properties of possible two-nucleon bound states in the nuclear medium. The comparison between reaction matrices found via the numerical solution of the Bethe-Goldstone integral equation and the straightforward Hamiltonian diagonalization shows a high accuracy of the method suggested. The proposed fully discrete approach opens a new way to an accurate treatment of two- and three-particle correlations in nuclear matter on the basis of the three-particle Bethe-Faddeev equation by an effective Hamiltonian diagonalization procedure.
Jeans Analysis for Dwarf Spheroidal Galaxies in Wave Dark Matter
Chen, Shu-Rong; Chiueh, Tzihong
2016-01-01
Observations suggest that dwarf spheroidal (dSph) galaxies exhibit large constant-density cores in the centers, which can hardly be explained by dissipationless cold dark matter simulations. Wave dark matter (${\\psi {\\rm DM}}$), characterized by a single parameter, the dark matter particle mass $m_{\\psi}$, predicts a central soliton core in every galaxy arising from quantum pressure against gravity. Here we apply Jeans analysis to the kinematic data of eight classical dSphs so as to constrain $m_{\\psi}$, and obtain $m_{\\psi}=1.18_{-0.24}^{+0.28}\\times10^{-22}{\\,\\rm eV}$ and $m_{\\psi}=1.79_{-0.33}^{+0.35}\\times10^{-22}{\\,\\rm eV}~(2\\sigma)$ using the observational data sets of Walker et al. (2007) and Walker et al. (2009b), respectively. We show that the estimate of $m_{\\psi}$ is sensitive to the dSphs kinematic data sets and is robust to various models of stellar density profile. We also consider multiple stellar subpopulations in dSphs and find consistent results. This mass range of $m_{\\psi}$ is in good agre...
Index of refraction of molecular nitrogen for sodium matter waves
Loreau, J; Dalgarno, A
2013-01-01
We calculate the index of refraction of sodium matter waves propagating through a gas of nitrogen molecules. We use a recent ab initio potential for the ground state of the NaN_2 Van der Waals complex to perform quantal close-coupling calculations and compute the index of refraction as a function of the projectile velocity. We obtain good agreement with the available experimental data. We show that the refractive index contains glory oscillations, but that they are damped by the averaging over the thermal motion of the N_2 molecules. These oscillations appear at lower temperatures and projectile velocity. We also investigate the behavior of the refractive index at low temperature and low projectile velocity to show its dependence on the rotational state of N_2, and discuss the advantage of using diatomic molecules as projectiles.
Filtering of matter wave vibrational states via spatial adiabatic passage
Loiko, Yu; Corbalán, R; Birkl, G; Mompart, J; 10.1103/PhysRevA.83.033629
2011-01-01
We discuss the filtering of the vibrational states of a cold atom in an optical trap, by chaining this trap with two empty ones and controlling adiabatically the tunneling. Matter wave filtering is performed by selectively transferring the population of the highest populated vibrational state to the most distant trap while the population of the rest of the states remains in the initial trap. Analytical conditions for two-state filtering are derived and then applied to an arbitrary number of populated bound states. Realistic numerical simulations close to state-of-the-art experimental arrangements are performed by modeling the triple well with time dependent P\\"oschl-Teller potentials. In addition to filtering of vibrational states, we discuss applications for quantum tomography of the initial population distribution and engineering of atomic Fock states that, eventually, could be used for tunneling assisted evaporative cooling.
Experimental methods of molecular matter-wave optics.
Juffmann, Thomas; Ulbricht, Hendrik; Arndt, Markus
2013-08-01
We describe the state of the art in preparing, manipulating and detecting coherent molecular matter. We focus on experimental methods for handling the quantum motion of compound systems from diatomic molecules to clusters or biomolecules.Molecular quantum optics offers many challenges and innovative prospects: already the combination of two atoms into one molecule takes several well-established methods from atomic physics, such as for instance laser cooling, to their limits. The enormous internal complexity that arises when hundreds or thousands of atoms are bound in a single organic molecule, cluster or nanocrystal provides a richness that can only be tackled by combining methods from atomic physics, chemistry, cluster physics, nanotechnology and the life sciences.We review various molecular beam sources and their suitability for matter-wave experiments. We discuss numerous molecular detection schemes and give an overview over diffraction and interference experiments that have already been performed with molecules or clusters.Applications of de Broglie studies with composite systems range from fundamental tests of physics up to quantum-enhanced metrology in physical chemistry, biophysics and the surface sciences.Nanoparticle quantum optics is a growing field, which will intrigue researchers still for many years to come. This review can, therefore, only be a snapshot of a very dynamical process.
Matter, dark matter and gravitational waves from a GUT-scale U(1) phase transition
Domcke, Valerie
2013-09-15
The cosmological realization of the spontaneous breaking of B-L, the difference of baryon and lepton number, can generate the initial conditions for the hot early universe. In particular, we show that entropy, dark matter and a matter-antimatter asymmetry can be produced in accordance with current observations. If B-L is broken at the grand unification scale, F-term hybrid inflation can be realized in the false vacuum of unbroken B-L. The phase transition at the end of inflation, governed by tachyonic preheating, spontaneously breaks the U(1){sub B-L} symmetry and sets the initial conditions for the following perturbative reheating phase. We provide a detailed, time-resolved picture of the reheating process. The competition of cosmic expansion and entropy production leads to an intermediate plateau of constant temperature, which controls both the generated lepton asymmetry and the dark matter abundance. This enables us to establish relations between the neutrino and superparticle mass spectrum, rendering this mechanism testable. Moreover, we calculate the entire gravitational wave spectrum for this setup. This yields a promising possibility to probe cosmological B - L breaking with forthcoming gravitational wave detectors such as eLISA, advanced LIGO and BBO/DECIGO. The largest contribution is obtained from cosmic strings which is, for typical parameter values, at least eight orders of magnitude higher then the contribution from inflation. Finally, we study the possibility of realizing hybrid inflation in a superconformal framework. We find that superconformal D-term inflation is an interesting possibility generically leading to a two-field inflation model, but in its simplest version disfavoured by the recently published Planck data.
Integrable multi atom matter-radiation models without rotating wave approximation
Kundu, Anjan
2004-01-01
Interacting matter-radiation models close to physical systems are proposed, which without rotating wave approximation and with matter-matter interactions are Bethe ansatz solvable. This integrable system is constructed from the elliptic Gaudin model at high spin limit, where radiative excitation can be included perturbatively.
Sound Wave in Hot Dense Matter Created in Heavy Ion Collision
Sun, X.; Yang, Z.
2005-01-01
A model to study the sound wave in hot dense matter created in heavy ion collisions by jet is proposed.The preliminary data of jet shape analysis of PHENIX Collaboration for all centralities and two directions is well explained in this model. Then the wavelength of the sound wave, the natural frequency of the hot dense matter and the speed of sound wave are estimated from the fit.
Dual Matter-Wave Inertial Sensors in Weightlessness
Barrett, Brynle; Chichet, Laure; Battelier, Baptiste; Lévèque, Thomas; Landragin, Arnaud; Bouyer, Philippe
2016-01-01
Quantum technology based on cold-atom interferometers is showing great promise for fields such as inertial sensing and fundamental physics. However, the best precision achievable on Earth is limited by the free-fall time of the atoms, and their full potential can only be realized in Space where interrogation times of many seconds will lead to unprecedented sensitivity. Various mission scenarios are presently being pursued which plan to implement matter-wave inertial sensors. Toward this goal, we realize the first onboard operation of simultaneous $^{87}$Rb $-$ $^{39}$K interferometers in the weightless environment produced during parabolic flight. The large vibration levels ($10^{-2}~g/\\sqrt{\\rm Hz}$), acceleration range ($0-1.8~g$) and rotation rates ($5$ deg/s) during flight present significant challenges. We demonstrate the capability of our dual-quantum sensor by measuring the E\\"{o}tv\\"{o}s parameter with systematic-limited uncertainties of $1.1 \\times 10^{-3}$ and $3.0 \\times 10^{-4}$ during standard- a...
Matter-wave diffraction at the natural limit
Brand, Christian; Sclafani, Michele; Knobloch, Christian; Lilach, Yigal; Juffmann, Thomas; Kotakoski, Jani; Mangler, Clemens; Winter, Andreas; Turchanin, Andrey; Meyer, Jannik; Cheshnovsky, Ori; Arndt, Markus
2016-05-01
The high sensitivity of matter-wave interferometry experiments to forces and perturbations makes them an essential tool for precision measurements and tests of quantum physics. While mostly grating made of laser-light are used, material gratings have the advantage that they are independent of the particle's internal properties. This makes them universally applicable. However, the molecules will experience substantial van der Waals shifts while passing the grating slits, which suggests limiting this perturbation by reducing the material thickness. In a comprehensive study we compared the van der Waals interactions for free-standing gratings made from single and double layer graphene to masks commonly used in atom interferometry. From the population of high fringe orders we deduce a surprisingly strong electrical interaction between the polarizable molecules and the nanomasks. As even for these thinnest diffraction elements which-path information is not shared with the environment, we interpret this as an experimental affirmation of Bohr's arguments in his famous debate with Einstein.
"Superman" Star Christopher Reeve Dies at 52
Jim Fitzgerald; 李邦珍
2004-01-01
@@ Superman actor Christopher Reeve, who turned personal tragedy into a public crusade① and from his wheelchair became the nation's most recognizable spokesman for spinal cord research, has died. He was 52. Reeve died Sunday of complications② from an infection caused by a bedsore③. He went into cardiac arrest④ Saturday, while at his Pound Ridge home, then fell into a coma⑤ and died Sunday at a hospital surrounded by his family, his publicist said. His advocacy for stem cell research helped it emerge as a major campaign issue between President Bush and Sen. John Kerry. His name was even mentioned by Kerry during the second presidential debate on Friday.
Christoph Kummerer (Pocketnoise) / Christoph Kummerer ; interv. Tilman Baumgärtel
Kummerer, Christoph, 1974-
2006-01-01
Austria kunstnikust, muusikust ja programmeerijast Christoph Kummererist (sünd. 1974), kes teeb Gameboyga tehnomuusikat. Loodud tarkvara nimetab ta Pocketnoise'iks, oma kompositsioonide levitamiseks kasutab võrgukaubamärki pilot.fm, mille ta asutas eksperimentaalse elektroonilise online-muusika levitamiseks. 30. I 2001 toimunud telefoniintervjuu kunstniku ja muusikuga
Search for light scalar dark matter with atomic gravitational wave detectors
Arvanitaki, Asimina; Hogan, Jason M; Rajendran, Surjeet; Van Tilburg, Ken
2016-01-01
We show that gravitational wave detectors based on a type of atom interferometry are sensitive to ultralight scalar dark matter. Such dark matter can cause temporal oscillations in fundamental constants with a frequency set by the dark matter mass, and amplitude determined by the local dark matter density. The result is a modulation of atomic transition energies. This signal is ideally suited to a type of gravitational wave detector that compares two spatially separated atom interferometers referenced by a common laser. Such a detector can improve on current searches for electron-mass or electric-charge modulus dark matter by up to 10 orders of magnitude in coupling, in a frequency band complementary to that of other proposals. It demonstrates that this class of atomic sensors is qualitatively different from other gravitational wave detectors, including those based on laser interferometry. By using atomic-clock-like interferometers, laser noise is mitigated with only a single baseline. These atomic sensors ca...
On Wave Dark Matter, Shells in Elliptical Galaxies, and the Axioms of General Relativity
Bray, Hubert L
2012-01-01
This paper is a sequel to the author's paper entitled "On Dark Matter, Spiral Galaxies, and the Axioms of General Relativity" [arXiv:1004.4016] which explored a geometrically natural axiomatic definition for dark matter modeled by a scalar field satisfying the Einstein-Klein-Gordon wave equations which, after much calculation, was shown to be consistent with the observed spiral and barred spiral patterns in disk galaxies. We give an update on where things stand on this "wave dark matter" model of dark matter (aka scalar field dark matter and boson stars), an interesting alternative to the WIMP model of dark matter, and discuss how it has the potential to help explain the long-observed interleaved shell patterns, also known as ripples, in the images of elliptical galaxies.
2015-05-05
AND SUBTITLE LASER-DRIVEN ULTRA-RELATIVISTIC PLASMAS - NUCLEAR FUSION IN COULOMB SHOCK WAVES, ROUGE WAVES, AND BACKGROUND MATTER. 5a. CONTRACT...blackbody radiation on free electrons .........................9 2.vi. Proposal of ultimate test of laser nuclear fusion efficiency in clusters...domain of energies and temperatures, with applications in particular to controlled nuclear fusion . 2. Final technical report on the grant #F49620-11-1
Self-induced dipole force and filamentation instability of a matter wave
Saffman, M.
1998-01-01
The interaction of copropagating electromagnetic and matter waves is described with a set of coupled higher-order nonlinear Schrodinger equations. Optical self-focusing modulates an initially planar wave leading to the generation of dipole forces on the atoms. Atomic channeling due to the dipole...
Coherent control of light-matter interactions in polarization standing waves
Fang, Xu; MacDonald, Kevin F.; Plum, Eric; Zheludev, Nikolay I.
2016-08-01
We experimentally demonstrate that standing waves formed by two coherent counter-propagating light waves can take a variety of forms, offering new approaches to the interrogation and control of polarization-sensitive light-matter interactions in ultrathin (subwavelength thickness) media. In contrast to familiar energy standing waves, polarization standing waves have constant electric and magnetic energy densities and a periodically varying polarization state along the wave axis. counterintuitively, anisotropic ultrathin (meta)materials can be made sensitive or insensitive to such polarization variations by adjusting their azimuthal angle.
2017 ISCB Overton Prize: Christoph Bock.
Fogg, Christiana N; Kovats, Diane E; Berger, Bonnie
2017-01-01
The International Society for Computational Biology (ISCB) each year recognizes the achievements of an early to mid-career scientist with the Overton Prize. This prize honors the untimely death of Dr. G. Christian Overton, an admired computational biologist and founding ISCB Board member. Winners of the Overton Prize are independent investigators who are in the early to middle phases of their careers and are selected because of their significant contributions to computational biology through research, teaching, and service. ISCB is pleased to recognize Dr. Christoph Bock, Principal Investigator at the CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences in Vienna, Austria, as the 2017 winner of the Overton Prize. Bock will be presenting a keynote presentation at the 2017 International Conference on Intelligent Systems for Molecular Biology/European Conference on Computational Biology (ISMB/ECCB) in Prague, Czech Republic being held during July 21-25, 2017.
"Superman" Star Christopher Reeve Dies at 52
Jim; Fitzgerald; 李邦珍
2004-01-01
克里斯托佛·里夫(Christopher Reeve)生于1952年9月25日,曾是美国著名的影星,由他主演的影片《超人》(Superman)不仅在美国红极一时,而且风靡全世界。他于1995年因遭车祸而全身瘫痪之后积极献身于干细胞研究,并成为脊髓(spinal cord)研究的著名号召者。他于2004年10月11日于纽约去世,享年52岁。
Development of a portable matter-wave gravimeter
Desruelle, B.; Menoret, V.; Bouyer, P.; Landragin, A.
2013-12-01
This paper presents the results of the research activities conducted by our company for the development of its Absolute Quantum Gravimeter. This instrument relies on the utilization of a free-falling cloud of cold rubidium atoms, whose vertical acceleration is characterized using advanced matter-wave interferometry techniques. In order to meet the tight requirements expressed by geophysicists for field utilization, we have implemented several technological innovations, which allow us to combine state-of-the-art performance with simple operation and excellent transportability. The architecture of our gravimeter is based on the following innovations: - a hollow pyramidal reflector allows us to achieve all the functions (trapping, cooling, atomic state selection, interferometry and detection) with a single laser beam [1]. This scheme leads to a drastic simplification of the sensor head, and a strong reduction of its mass and volume. - An all-fibered laser system based on the frequency doubling of a seed laser operating at 1560 nm [2]. With this approach, we are able to obtain a very compact, reliable and easy to use laser source capable of generating two optical frequencies in the 780.23 nm range with an output power in excess of 250 mW, an excellent polarization extinction ratio and a fast tunability. - a real-time system dedicated to the compensation of ground vibrations [3]. This technique is based on the operation of a low noise seismometer, whose AC acceleration signal is used to correct the atomic interferometer signal. We give a detailed presentation of the instrument architecture and summarize the experimental results we have obtained with our first generation prototype. [1] A cold atom pyramidal gravimeter with a single laser beam, Q. Bodart et al, Appl. Phys. Lett. 96, 134101 (2010) [2] "Light-pulse atom interferometry in microgravity", G. Stern et al, Eur. Phys. J. D 53, 353-357 (2009) [3]. "Limits in the sensitivity of a compact atomic interferometer ", J
Christoph Rothmann and Copernicanism. (German Title: Christoph Rothmann und der Copernicanismus)
Granada, Miguel A.
Christoph Rothmann belonged to the first convinced adherents of heliocentric cosmology. The contribution discusses Rothmann's relevant remarks, which are found in his paper of 1586 «Scriptum de cometa», dealing with the comet of the previous year. Rothmann also vehemently defended his concepts in a letter to Tycho Brahe dating from September, 1588, in which he rejected both the old geocentric and Brahe's geoheliocentric system.
Daxecker, Franz
The newly found print "Theses Theologicae" is Christoph Scheiner's disputation, which took place on June 30, 1609. The title page contains Scheiner's name, presenting him as the author who is responsible for (respondente) 50 theses. The theses deal with the Summa theologica of Saint Thomas Aquinas: Nature of God, Creation, Morality, Canon Law, Grace, Faith, Justice, Devotion to Godd and the Saints, Divine Word and Sacraments.
Matter-wave interferometry in a double well on an atom chip
Schumm, Thorsten; Hofferberth, S.; Andersson, L. M.
2005-01-01
Matter-wave interference experiments enable us to study matter at its most basic, quantum level and form the basis of high-precision sensors for applications such as inertial and gravitational field sensing. Success in both of these pursuits requires the development of atom-optical elements...... that can manipulate matter waves at the same time as preserving their coherence and phase. Here, we present an integrated interferometer based on a simple, coherent matter-wave beam splitter constructed on an atom chip. Through the use of radio-frequency-induced adiabatic double-well potentials, we...... demonstrate the splitting of Bose-Einstein condensates into two clouds separated by distances ranging from 3 to 80 μm, enabling access to both tunnelling and isolated regimes. Moreover, by analysing the interference patterns formed by combining two clouds of ultracold atoms originating from a single...
Workshop on Waves and Particles in Light and Matter
Van der Merwe, Alwyn; Waves and Particles in Light and Matter
1994-01-01
The Great Veil, Reality, and Louis de Broglie (O. Costa de Beauregard). The Fallacy of the Arguments Against Local Realism in Quantum Phenomena (A.O. Barut). Restoring Locality with FasterThanLight Velocities (P.H. Eberhard). The WaveParticle Duality and the AharonovBohm Effect (M. Ferrero, E. Santos). De Broglie's Waves in Space and Time (A. Garuccio). Interferometry with De Broglie Waves (F. Hasselbach). Quantum Mechanics of Ultracold Neutrons (V.K. Ignatovich). The Physical Interpretation of Special Relativity (S.J. Prokhovnik). Quantum Neutron Optics (H. Rauch). Some Comments on th
Do Neutrino Wave Functions Overlap and Does it Matter?
Li, Cheng-Hsien
2016-01-01
Studies of neutrinos commonly ignore anti-symmetrization of their wave functions. This implicitly assumes that either spatial wave functions for neutrinos with approximately the same momentum do not overlap or their overlapping has no measurable consequences. We examine these assumptions by considering the evolution of three-dimensional neutrino wave packets (WPs). We find that it is perfectly adequate to treat accelerator and reactor neutrinos as separate WPs for typical experimental setup. While solar and supernova neutrinos correspond to overlapping WPs, they can be treated effectively as non-overlapping for analyses of their detection.
Compact dark matter objects, asteroseismology, and gravitational waves radiated by sun
Pokrovsky, Yu. E., E-mail: Pokrovskiy-YE@nrcki.ru [National Research Center Kurchatov Institute (Russian Federation)
2015-12-15
The solar surface oscillations observed by Crimean Astrophysical Observatory and Solar Helioseismic Observatory are considered to be excited by a small fraction of Dark Matter in form of Compact Dark Matter Objects (CDMO) in the solar structure. Gravitational Waves (GW) radiated by these CDMO are predicted to be the strongest at the Earth and are easily detectable by European Laser Interferometer Space Antenna or by Gravitational-Wave Observatory “Dulkyn” which can solve two the most challenging tasks in the modern physics: direct detection of GW and DM.
Long-living BLOCH oscillations of matter waves in periodic potentials.
Salerno, M; Konotop, V V; Bludov, Yu V
2008-07-18
The dynamics of matter waves in linear and nonlinear optical lattices subject to a spatially uniform linear force is studied both analytically and numerically. It is shown that by properly designing the spatial dependence of the scattering length it is possible to induce long-living Bloch oscillations of gap-soliton matter waves in optical lattices. This occurs when the effective nonlinearity and the effective mass of the soliton have opposite signs for all values of the crystal momentum in the Brillouin zone. The results apply to all systems modeled by the periodic nonlinear Schrödinger equation, including propagation of light in photonic and photorefractive crystals with tilted band structures.
Compact dark matter objects, asteroseismology, and gravitational waves radiated by sun
Pokrovsky, Yu. E.
2015-12-01
The solar surface oscillations observed by Crimean Astrophysical Observatory and Solar Helioseismic Observatory are considered to be excited by a small fraction of Dark Matter in form of Compact Dark Matter Objects (CDMO) in the solar structure. Gravitational Waves (GW) radiated by these CDMO are predicted to be the strongest at the Earth and are easily detectable by European Laser Interferometer Space Antenna or by Gravitational-Wave Observatory "Dulkyn" which can solve two the most challenging tasks in the modern physics: direct detection of GW and DM.
On gravitational wave-Cherenkov radiation from photons when passing through diffused dark matters
Yi, Shu-Xu
2017-03-01
Analogous to Cherenkov radiation, when a particle moves faster than the propagation velocity of gravitational wave in matter (v > cg), we expect gravitational wave-Cherenkov radiation (GWCR). In the situation that a photon travels across diffuse dark matters, the GWCR condition is always satisfied, photon will thence lose its energy all along the path. This effect has long been ignored in the practice of astrophysics and cosmology without justification with serious calculation. We study this effect for the first time, and shows that this energy loss time of the photon is far longer than the Hubble time and therefore justify the practice of ignoring this effect in the context of astrophysics.
Concept of an ionizing time-domain matter-wave interferometer
Nimmrichter, Stefan; Haslinger, Philipp; Hornberger, Klaus; ARNDT, Markus
2011-01-01
We discuss the concept of an all-optical and ionizing matter-wave interferometer in the time domain. The proposed setup aims at testing the wave nature of highly massive clusters and molecules, and it will enable new precision experiments with a broad class of atoms, using the same laser system. The propagating particles are illuminated by three pulses of a standing ultraviolet laser beam, which detaches an electron via efficient single photon-absorption. Optical gratings may have periods as ...
Measuring the Gouy Phase of Matter Waves using Singular Atom Optics with Spinor BECs
Schultz, Justin T.; Hansen, Azure; Murphree, Joseph D.; Jayaseelan, Maitreyi; Bigelow, Nicholas P.
2016-05-01
The Gouy phase is a propagation-dependent geometric phase found in confined waves as they propagate through a focus. Although it has been observed and studied extensively both in scalar and vector optical beams as well as in electron vortex beams, it has not yet been directly observed in ultracold matter waves. The Schrödinger equation has the same form as the paraxial wave equation from electromagnetism; expansion of a BEC upon release from a trap has the same mathematical form as a beam propagating away from a focus. We employ and extend this analogy between coherent optical beams and coherent matter waves to include spin angular momentum (polarization), which enables us measure the matter wave Gouy phase using coreless vortex spin textures in spinor BECs. Because the Gouy phase is dependent on the orbital angular momentum of the wave, the vortex and core states acquire different Gouy phase shifts. Parameters that are sensitive to the relative phase such as two-dimensional maps of the Stokes parameters rotate during evolution due to this phase difference. Using atom-optic polarimetry we can access the evolution of the atomic Stokes parameters and observe this rotation.
Shock Wave Attenuation Using Foam Obstacles: Does Geometry Matter?
Hongjoo Jeon
2015-06-01
Full Text Available A shock wave impact study on open and closed cell foam obstacles was completed to assess attenuation effects with respect to different front face geometries of the foam obstacles. Five different types of geometries were investigated, while keeping the mass of the foam obstacle constant. The front face, i.e., the side where the incident shock wave impacts, were cut in geometries with one, two, three or four convergent shapes, and the results were compared to a foam block with a flat front face. Results were obtained by pressure sensors located upstream and downstream of the foam obstacle, in addition to high-speed schlieren photography. Results from the experiments show no significant difference between the five geometries, nor the two types of foam.
The role of Mie scattering in the seeding of matter-wave superradiance
Bachelard, Romain; Courteille, Philippe W; Piovella, Nicola; Stehle, Christian; Zimmermann, Claus; Slama, Sebastian
2012-01-01
Matter-wave superradiance is based on the interplay between ultracold atoms coherently organized in momentum space and a backscattered wave. Here, we show that this mechanism may be triggered by Mie scattering from the atomic cloud. We show that the system evolves into a superposition of states, where the scattering process imprints a {\\it phase grating} on the atomic dipoles. This grating generates coherent emission even when there is at most one excited atom in the system at a time, contributing to the backward light wave onset. The atomic recoil 'halos' created by the scattered light exhibit a strong anisotropy, in contrast to single-atom scattering.
Kampel, Nir Shlomo; Griesmaier, Axel Rudolf; Steenstrup, Mads Peter Hornbak;
2012-01-01
We investigate experimentally the effects of light assisted collisions on the coherence between momentum states in Bose-Einstein condensates. The onset of superradiant Rayleigh scattering serves as a sensitive monitor for matter-wave coherence. A subtle interplay of binary and collective effects...
Parametric amplification of matter waves in dipolar spinor Bose-Einstein condensates
Deuretzbacher, F.; Gebreyesus, G.; Topic, O.;
2010-01-01
Spin-changing collisions may lead under proper conditions to the parametric amplification of matter waves in spinor Bose-Einstein condensates. Magnetic dipole-dipole interactions, although typically very weak in alkali-metal atoms, are shown to play a very relevant role in the amplification process...
P-wave holographic superconductor/insulator phase transitions affected by dark matter sector
Rogatko, Marek
2015-01-01
The holographic approach to building the p-wave superconductors results in three different models: the Maxwell-vector, the SU(2) Yang-Mills and the helical one. In the probe limit approximation, we analytically examine the properties of the first two models in the theory with {\\it dark matter} sector. It turns out that the effect of dark matter on the Maxwell-vector p-wave model is the same as on the s-wave superconductor studied earlier. For the non-Abelian model we study the phase transitions between p-wave holographic insulator/superconductor and metal/superconductor. Studies of marginally stable modes in the theory under consideration allow us to determine features of p-wave holographic droplet in a constant magnetic field. The superconducting transition temperature increases with the growth of the {\\it dark matter} sector coupling constant $\\alpha$, while the critical chemical potential $\\mu_c$ for the quantum phase transition between insulator and metal is a decreasing function of $\\alpha$.
Detecting the gravitational wave background from primordial black hole dark matter
Clesse, Sebastien
2016-01-01
The black hole merging rates inferred after the gravitational-wave detection by Advanced LIGO/VIRGO and the relatively high mass of the progenitors are consistent with models of dark matter made of massive primordial black holes (PBH). PBH binaries emit gravitational waves in a broad range of frequencies that will be probed by future space interferometers (LISA) and pulsar timing arrays (PTA). The amplitude of the stochastic gravitational-wave background expected for PBH dark matter is calculated taking into account various effects such as initial eccentricity of binaries, PBH velocities, mass distribution and clustering. It allows a detection by the LISA space interferometer, and possibly by the PTA of the SKA radio-telescope. Interestingly, one can distinguish this background from the one of non-primordial massive binaries through a specific frequency dependence, resulting from the maximal impact parameter of binaries formed by PBH capture, depending on the PBH velocity distribution and their clustering pro...
Matter-wave dark solitons in box-like traps
Sciacca, M; Parker, N G
2016-01-01
Motivated by the experimental development of quasi-homogeneous Bose-Einstein condensates confined in box-like traps, we study numerically the dynamics of dark solitons in such traps at zero temperature. We consider the cases where the side walls of the box potential rise either as a power-law or a Gaussian. While the soliton propagates through the homogeneous interior of the box without dissipation, it typically dissipates energy during a reflection from a wall through the emission of sound waves, causing a slight increase in the soliton's speed. We characterise this energy loss as a function of the wall parameters. Moreover, over multiple oscillations and reflections in the box-like trap, the energy loss and speed increase of the soliton can be significant, although the decay eventually becomes stabilized when the soliton equilibrates with the ambient sound field.
Gravitational waves from dark matter collapse in a star
Kurita, Yasunari
2016-01-01
We investigate the collapse of clusters of weakly interacting massive particles (WIMPs) in the core of a Sun-like star and the possible formation of mini-black holes and the emission of gravity waves. When the number of WIMPs is small, thermal pressure balances the WIMP cluster's self gravity. If the number of WIMPs is larger than a critical number, thermal pressure cannot balance gravity and the cluster contracts. If WIMPs are collisionless and bosonic, the cluster collapses directly to form a mini-black hole. For fermionic WIMPs, the cluster contracts until it is sustained by Fermi pressure, forming a small compact object. If the fermionic WIMP mass is smaller than $4\\times 10^2$ GeV, the radius of the compact object is larger than its Schwarzschild radius and Fermi pressure temporally sustains its self gravity, halting the formation of a black hole. If the fermionic WIMP mass is larger than $4\\times 10^2$ GeV, the radius is smaller than its Schwarzschild radius and the compact object becomes a mini-black h...
Non-isentropic layers in matter behind shock and ramp compression waves
Khishchenko, Konstantin V
2014-01-01
According to the ideal fluid dynamics approach, the temperature and entropy values of a medium undergo a jump increase in the shock front as well as on contact interface between different materials after the shock wave propagation, but remain constant behind the shock front out of the contact interface. In the real condensed matter, the shock fronts and transition regions near the interfaces have finite thicknesses; therefore, the temperature field is disturbed around the interfaces. In this work, such disturbances are numerically analyzed for the problems of formation of the steady shock wave at impact and ramp loading of metals, reflection of the steady shock wave from a free surface, and the shock wave passing through the interface between two different materials. Theoretical analysis and computations show that the non-isentropic layers (the high-entropy ones with the increased temperature and the low-entropy ones with the decreased temperature) arise near the interfaces in the above problems of shock and ...
The Einstein-Klein-Gordon Equations, Wave Dark Matter, and the Tully-Fisher Relation
Goetz, Andrew S
2015-01-01
We examine the Einstein equation coupled to the Klein-Gordon equation for a complex-valued scalar field. These two equations together are known as the Einstein-Klein-Gordon system. In the low-field, non-relativistic limit, the Einstein-Klein-Gordon system reduces to the Poisson-Schr\\"odinger system. We describe the simplest solutions of these systems in spherical symmetry, the spherically symmetric static states, and some scaling properties they obey. We also describe some approximate analytic solutions for these states. The EKG system underlies a theory of wave dark matter, also known as scalar field dark matter (SFDM), boson star dark matter, and Bose-Einstein condensate (BEC) dark matter. We discuss a possible connection between the theory of wave dark matter and the baryonic Tully-Fisher relation, which is a scaling relation observed to hold for disk galaxies in the universe across many decades in mass. We show how fixing boundary conditions at the edge of the spherically symmetric static states implies T...
Gravitational Wave Signatures of Dark Matter Sub-Millimeter Primordial Black Holes
Davoudiasl, Hooman
2016-01-01
We entertain the possibility that primordial black holes of mass $\\sim (10^{24} - 10^{26})$ g, with sub-millimeter Schwarzschild radii, constitute all or a significant fraction of cosmic dark matter, as allowed by various constraints. In case such primordial black holes get captured in orbits around neutron stars or astrophysical black holes in our galactic neighborhood, gravitational waves from the resulting "David & Goliath" binaries could be detectable at Advanced LIGO or Advanced Virgo from days to years, for a range of possible parameters. The proposed Einstein Telescope would further expand the reach for dark matter primordial black holes in this search mode.
Evolutions of matter-wave bright soliton with spatially modulated nonlinearity
Yongshan Cheng; Fei Liu
2009-01-01
The evolution characteristics of a matter-wave bright soliton are investigated by means of the variational approach in the presence of spatially varying nonlinearity.It is found that the atom density envelope of the soliton is changed as a result of the spatial variation of the s-wave scattering length.The stable soliton can exist in appropriate initial conditions.The movement of the soliton depends on the sign and value of the coefficient of spatially modulated nonlinearity.These theoretical predictions are confirmed by the full numerical simulations of the one-dimensional Gross-Pitaevskii equation.
Cox, Kevin C; Wu, Baochen; Thompson, James K
2016-01-01
We demonstrate a method to generate spatially homogeneous entangled, spin-squeezed states of atoms appropriate for maintaining a large amount of squeezing even after release into the arm of a matter-wave interferometer or other free space quantum sensor. Using an effective intracavity dipole trap, we allow atoms to move along the cavity axis and time average their coupling to the standing wave used to generate entanglement via collective measurements, demonstrating 11(1) dB of directly observed spin squeezing. Our results show that time averaging in collective measurements can greatly reduce the impact of spatially inhomogeneous coupling to the measurement apparatus.
Zero-order filter for diffractive focusing of de Broglie matter waves
Eder, S. D.; Ravn, A. K.; Samelin, B.
2017-01-01
conditions the atom focusing at lower source stagnation pressures (broader velocity distributions) is better than what has previously been predicted. We present simulations with the software ray-tracing simulation package MCSTAS using a realistic helium source configuration, which gives very good agreement......The manipulation of neutral atoms and molecules via their de Broglie wave properties, also referred to asde Broglie matter wave optics, is relevant for several fields ranging from fundamental quantum mechanics testsand quantum metrology to measurements of interaction potentials and new imaging...
Constraining the MIT Bag Model of Quark Matter with Gravitational Wave Observations
Benhar, O; Gualtieri, L; Marassi, S; Benhar, Omar; Ferrari, Valeria; Gualtieri, Leonardo; Marassi, Stefania
2006-01-01
Most theoretical studies of strange stars are based on the MIT bag model of quark matter, whose main parameter, the bag constant B, is only loosely constrained by phenomenology. We discuss the possibility that detection of gravitational waves emitted by a compact star may provide information on both the nature of the source and the value of B. Our results show that the combined knowledge of the frequency of the emitted gravitational wave and of the mass or the radiation radius of the source allows one to discriminate between strange stars and neutron stars and set stringent bounds on the bag constants.
Localization of Matter Fields in the 5D Standing Wave Braneworld
Gogberashvili, Merab
2012-01-01
We investigate the localization problem of matter fields within the 5D standing wave braneworld. In this model the brane emits anisotropic waves into the bulk with different amplitudes along different spatial dimensions. We show that in the case of increasing warp factor there exist the pure gravitational localization of all kinds of quantum and classical particles on the brane. For classical particles the anisotropy of the background metric is hidden, brane fields exhibit standard Lorentz symmetry in spite of anisotropic nature of the primordial 5D metric.
Canuel B.
2014-01-01
Full Text Available We are building a hybrid detector of new concept that couples laser and matter-wave interferometry to study sub Hertz variations of the strain tensor of space-time and gravitation. Using a set of atomic interferometers simultaneously manipulated by the resonant optical field of a 200 m cavity, the MIGA instrument will allow the monitoring of the evolution of the gravitational field at unprecedented sensitivity, which will be exploited both for geophysical studies and for Gravitational Waves (GWs detection. This new infrastructure will be embedded into the LSBB underground laboratory, ideally located away from major anthropogenic disturbances and benefitting from very low background noise.
Kadlecová, Hedvika; Weber, Stefan; Korn, Georg
2016-01-01
We analyze theoretical models of gravitational waves generation in the interaction of high intensity laser with matter, namely ablation and piston models. We analyse the generated gravitational waves in linear approximation of gravitational theory. We derive the analytical formulas and estimates for the metric perturbations and the radiated power of generated gravitational waves. Furthermore we investigate the characteristics of polarization and the behaviour of test particles in the presence of gravitational wave which will be important for the detection.
Matter-wave beam splitter on an atom chip for a portable atom interferometer
Kim, S. J.; Yu, H.; Gang, S. T.; Kim, J. B.
2017-05-01
We constructed a matter-wave beam splitter on an atom chip using a 87Rb Bose-Einstein condensate. Using radio-frequency-induced double-well potentials, we were able to coherently split a BEC into two clouds separated by distances ranging from 2.8 to 57 μm. Interference between these two freely expanding BECs was observed, confirming the coherence of the matter-wave beam splitter. We are able to control the distance and the angle between the split BECs by varying the rf-field's amplitude, frequency, or polarization. From the perspective of practical use, our BEC manipulation system is suitable for application to interferometry. It is compact, and by anodic bonding the atom chip to the vacuum cell, the repetition rate is kept high. The portable system occupies a volume of 0.5 m3 and operates at a repetition rate as high as 0.2 Hz using a commercial vacuum product.
Gravitational waves in Fully Constrained Formulation in a dynamical spacetime with matter content
Cordero-Carrion, Isabel; Cerda-Duran, Pablo [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741, Garching (Germany); Ibanez, Jose MarIa, E-mail: chabela@mpa-garching.mpg.de, E-mail: cerda@mpa-garching.mpg.de, E-mail: jose.m.ibanez@uv.es [Departamento de AstronomIa y Astrofisica, Universidad de Valencia, C/ Dr. Moliner 50, E-46100 Burjassot, Valencia (Spain)
2011-09-22
We analyze numerically the behaviour of the hyperbolic sector of the Fully Constrained Formulation (FCF) (Bonazzola et al. 2004). The numerical experiments allow us to be confident in the performances of the upgraded version of the CoCoNuT code (Dimmelmeier et al. 2005) by replacing the Conformally Flat Condition (CFC), an approximation of Einstein equations, by FCF. First gravitational waves in FCF in a dynamical spacetime with matter content will be shown.
Fortov, Vladimir E.
2007-04-01
The physical properties of hot dense matter over a broad domain of the phase diagram are of immediate interest in astrophysics, planetary physics, power engineering, controlled thermonuclear fusion, impulse technologies, enginery, and several special applications. The use of intense shock waves in dynamic physics and high-pressure chemistry has made the exotic high-energy-density states of matter a subject of laboratory experiments and enabled advancing by many orders of magnitude along the pressure scale to range into the megabars and even gigabars. The present report reviews the latest experimental research involving shock waves in nonideal plasmas under conditions of strong collective interparticle interaction. The results of investigations into the thermodynamic, transport, and optical properties of strongly compressed hot matter, as well as into its composition and conductivity, are discussed. Experimental techniques for high energy density cumulation, the drivers of intense shock waves, and methods for the fast diagnostics of high-energy plasma are considered. Also discussed are compression-stimulated physical effects: pressure-induced ionization, plasma phase transitions, the deformation of bound states, plasma blooming ('transparentization' of plasma), etc. Suggestions for future research are put forward.
From quantum turbulence to statistical atom optics: new perspectives in speckle matter wave
Tavares, P E S; Telles, G D; Impens, F; Kaiser, R; Bagnato, V S
2016-01-01
Quantum Turbulence, the chaotic configuration of tangled quantized vortex lines, can be analyzed from the matter wave perspective in instead of the traditional fluid perspective. We report the observation of a remarkable similarity in between the dynamics of a freely expanding turbulent Bose-Einstein condensate and the propagation of an optical speckle pattern. Both follow very similar basic propagation characteristics. The second-order correlation is calculated and the typical correlation length of the two phenomena is used to substantiate the observations. The analogy between an expanding turbulent atomic condensate and a traveling optical speckle creates exciting prospects to investigate disordered quantum matter including the possibilities of a 3D speckle matter field.
Gravitational wave signals of electroweak phase transition triggered by dark matter
Chao, Wei; Guo, Huai-Ke; Shu, Jing
2017-09-01
We study in this work a scenario that the universe undergoes a two step phase transition with the first step happened to the dark matter sector and the second step being the transition between the dark matter and the electroweak vacuums, where the barrier between the two vacuums, that is necessary for a strongly first order electroweak phase transition (EWPT) as required by the electroweak baryogenesis mechanism, arises at the tree-level. We illustrate this idea by working with the standard model (SM) augmented by a scalar singlet dark matter and an extra scalar singlet which mixes with the SM Higgs boson. We study the conditions for such pattern of phase transition to occur and especially for the strongly first order EWPT to take place, as well as its compatibility with the basic requirements of a successful dark matter, such as observed relic density and constraints of direct detections. We further explore the discovery possibility of this pattern EWPT by searching for the gravitational waves generated during this process in spaced based interferometer, by showing a representative benchmark point of the parameter space that the generated gravitational waves fall within the sensitivity of eLISA, DECIGO and BBO.
2000 Newbery Medal Winner: A Conversation with Christopher Paul Curtis.
Johnson, Nancy J.; Giorgis, Cyndi
2001-01-01
Presents an interview with 2000 Newbery Medal winner Christopher Paul Curtis. Reveals the author's journey as a reader and a writer, offers glimpses into the humor and upbeat attitude of Bud (the main character in Curtis' s award-winning book "Bud, Not Buddy"), and gives a peek into what readers can expect next from this award-winning author. (SR)
Ajakirjanik Bollyn : parvlaev Estonia uputati / Christopher Bollyn ; interv. Mirko Ojakivi
Bollyn, Christopher
2005-01-01
American Free Pressile töötav ajakirjanik Christopher Bollyn üritab saada kinnitust teooriale, et 1994. aasta sügisel veeti Estonial kõrgtehnoloogilist relvastust või kosmosetehnikat, mis pidi USA-sse jõudma. Kuna tehingu käigus kerkisid esile segavad asjaolud, uputati parvlaev ja tähtsamad tunnistajad "tehti kahjutuks"
2013-11-27
... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Christopher Williams: The Production..., 2003), I hereby determine that the objects to be included in the exhibition ``Christopher Williams:...
P-wave Annihilating Dark Matter from a Decaying Predecessor and the Galactic Center Excess
Choquette, Jeremie; Cornell, Jonathan M
2016-01-01
Dark matter (DM) annihilations have been widely studied as a possible explanation of excess gamma rays from the galactic center seen by Fermi/LAT. However most such models are in conflict with constraints from dwarf spheroidals. Motivated by this tension, we show that p-wave annihilating dark matter can easily accommodate both sets of observations due to the lower DM velocity dispersion in dwarf galaxies. Explaining the DM relic abundance is then challenging. We outline a scenario in which the usual thermal abundance is obtained through s-wave annihilations of a metastable particle, that eventually decays into the p-wave annihilating DM of the present epoch. The couplings and lifetime of the decaying particle are constrained by big bang nucleosynthesis, the cosmic microwave background and direct detection, but significant regions of parameter space are viable. A sufficiently large p-wave cross section can be found by annihilation into light mediators, that also give rise to Sommerfeld enhancement. A predictio...
Fourth American Physical Society Topical Conference on Shock Waves in Condensed Matter
Shock Waves in Condensed Matter
1986-01-01
The Fourth American Physical Society Topical Conference on Shock Waves in Condensed Matter was held in Spokane, Washington, July 22-25, 1985. Two hundred and fifty scientists and engineers representing thirteen countries registered at the conference. The countries represented included the United States of America, Australia, Canada, The People's Repub lic of China, France, India, Israel, Japan, Republic of China (Taiwan), United Kingdom, U. S. S. R, Switzerland and West Germany. One hundred and sixty-two technical papers, cov ering recent developments in shock wave and high pressure physics, were presented. All of the abstracts have been published in the September 1985 issue of the Bulletin of the American Physical Society. The topical conferences, held every two years since 1979, have become the principal forum for shock wave studies in condensed materials. Both formal and informal technical discussions regarding recent developments conveyed a sense of excitement. Consistent with the past conferences, th...
Dark Matter searches using gravitational wave bar detectors: quark nuggets and newtorites
Bassan, M; D'Antonio, S.; Fafone, V.; Giordano, G.; Marini, A.; Minenkov, Y.; Modena, I.; Pallottino, G.V.; Pizzella, G.; Rocchi, A.; Ronga, F.; Visco, M.
2016-01-01
Many experiments have searched for supersymmetric WIMP dark matter, with null results. This may suggest to look for more exotic possibilities, for example compact ultra-dense quark nuggets, widely discussed in literature with several different names. Nuclearites are an example of candidate compact objects with atomic size cross section. After a short discussion on nuclearites, the result of a nuclearite search with the gravitational wave bar detectors Nautilus and Explorer is reported. The geometrical acceptance of the bar detectors is 19.5 $\\rm m^2$ sr, that is smaller than that of other detectors used for similar searches. However, the detection mechanism is completely different and is more straightforward than in other detectors. The experimental limits we obtain are of interest because, for nuclearites of mass less than $10^{-5}$ g, we find a flux smaller than that one predicted considering nuclearites as dark matter candidates. Particles with gravitational only interactions (newtorites) are another examp...
Chala, Mikael [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Nardini, Germano [Bern Univ. (Switzerland). Inst. for Theoretical Physics; Sobolev, Ivan [Russian Academy of Sciences, Moscow (Russian Federation). Inst. for Nuclear Research; Moscow State Univ. (Russian Federation). Dept. of Particle Physics and Cosmology
2016-05-15
A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite Higgs version of this scenario, based on the coset SO(7)/SO(6). We show that by embedding the elementary fermions in appropriate representations of SO(7), all dominant interactions are described by only three free effective parameters. Within the model dependencies of the embedding, the theory predicts one of the singlets to be stable and responsible for the observed dark matter abundance. At the same time, the second singlet introduces new CP-violation phases and triggers a strong first-order EWPT, making electroweak baryogenesis feasible. It turns out that this scenario does not conflict with current observations and it is promising for solving the dark matter and baryon asymmetry puzzles. The tight predictions of the model will be accessible at the forthcoming dark matter direct detection and gravitational wave experiments.
Chala, Mikael; Nardini, Germano; Sobolev, Ivan
2016-09-01
A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite Higgs version of this scenario, based on the coset S O (7 )/S O (6 ). We show that by embedding the elementary fermions in appropriate representations of S O (7 ), all dominant interactions are described by only three free effective parameters. Within the model dependencies of the embedding, the theory predicts one of the singlets to be stable and responsible for the observed dark matter abundance. At the same time, the second singlet introduces new C P -violation phases and triggers a strong first-order EWPT, making electroweak baryogenesis feasible. It turns out that this scenario does not conflict with current observations and it is promising for solving the dark matter and baryon asymmetry puzzles. The tight predictions of the model will be accessible at the forthcoming dark matter direct detection and gravitational wave experiments.
The Sagnac effect: 20 years of development in matter-wave interferometry
Barrett, Brynle; Dutta, Indranil; Meunier, Matthieu; Canuel, Benjamin; Gauguet, Alexandre; Bouyer, Philippe; Landragin, Arnaud
2014-01-01
Since the first atom interferometry experiments in 1991, measurements of rotation through the Sagnac effect in open-area atom interferometers has been studied. These studies have demonstrated very high sensitivity which can compete with state-of-the-art optical Sagnac interferometers. Since the early 2000s, these developments have been motivated by possible applications in inertial guidance and geophysics. Most matter-wave interferometers that have been investigated since then are based on two-photon Raman transitions for the manipulation of atomic wave packets. Results from the two most studied configurations, a space-domain interferometer with atomic beams and a time-domain interferometer with cold atoms, are presented and compared. Finally, the latest generation of cold atom interferometers and their preliminary results are presented.
Gravitational Waves as a New Probe of Bose-Einstein Condensate Dark Matter
Dev, P S Bhupal; Ohmer, Sebastian
2016-01-01
There exists a class of ultralight Dark Matter (DM) models which could form a Bose-Einstein condensate (BEC) in the early universe and behave as a single coherent wave instead of individual particles in galaxies. We show that a generic BEC DM halo intervening along the line of sight of a gravitational wave (GW) signal could induce an observable change in the speed of GW, with the effective refractive index depending only on the mass and self-interaction of the constituent DM particles and the GW frequency. Hence, we propose to use the deviation in the speed of GW as a new probe of the BEC DM parameter space. With a multi-messenger approach to GW astronomy and/or with extended sensitivity to lower GW frequencies, the entire BEC DM parameter space can be effectively probed by our new method in the near future.
Canuel, B; Amand, L; Bertoldi, A; Cormier, E; Fang, B; Gaffet, S; Geiger, R; Harms, J; Holleville, D; Landragin, A; Lefèvre, G; Lhermite, J; Mielec, N; Prevedelli, M; Riou, I; Bouyer, P
2016-01-01
The Matter-Wave laser Interferometer Gravitation Antenna, MIGA, will be a hybrid instrument composed of a network of atom interferometers horizontally aligned and interrogated by the resonant field of an optical cavity. This detector will provide measurements of sub Hertz variations of the gravitational strain tensor. MIGA will bring new methods for geophysics for the characterization of spatial and temporal variations of the local gravity field and will also be a demonstrator for future low frequency Gravitational Wave (GW) detections. MIGA will enable a better understanding of the coupling at low frequency between these different signals. The detector will be installed underground in Rustrel (FR), at the "Laboratoire Souterrain Bas Bruit" (LSBB), a facility with exceptionally low environmental noise and located far away from major sources of anthropogenic disturbances. We give in this paper an overview of the operating mode and status of the instrument before detailing simulations of the gravitational backg...
Canuel, B.; Pelisson, S.; Amand, L.; Bertoldi, A.; Cormier, E.; Fang, B.; Gaffet, S.; Geiger, R.; Harms, J.; Holleville, D.; Landragin, A.; Lefèvre, G.; Lhermite, J.; Mielec, N.; Prevedelli, M.; Riou, I.; Bouyer, P.
2016-04-01
The Matter-Wave laser Interferometer Gravitation Antenna, MIGA, will be a hybrid instrument composed of a network of atom interferometers horizontally aligned and interrogated by the resonant field of an optical cavity. This detector will provide measurements of sub Hertz variations of the gravitational strain tensor. MIGA will bring new methods for geophysics for the characterization of spatial and temporal variations of the local gravity field and will also be a demonstrator for future low frequency Gravitational Wave (GW) detections. MIGA will enable a better understanding of the coupling at low frequency between these different signals. The detector will be installed underground in Rustrel (FR), at the "Laboratoire Souterrain Bas Bruit" (LSBB), a facility with exceptionally low environmental noise and located far away from major sources of anthropogenic disturbances. We give in this paper an overview of the operating mode and status of the instrument before detailing simulations of the gravitational background noise at the MIGA installation site.
Collisional-inhomogeneity-induced generation of matter-wave dark solitons
Wang, C. [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003-4515 (United States); Kevrekidis, P.G., E-mail: kevrekid@gmail.co [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003-4515 (United States); Horikis, T.P. [Department of Mathematics, University of Ioannina, Ioannina 45110 (Greece); Frantzeskakis, D.J. [Department of Physics, University of Athens, Panepistimiopolis, Zografos, Athens 15784 (Greece)
2010-08-16
We propose an experimentally relevant protocol for the controlled generation of matter-wave dark solitons in atomic Bose-Einstein condensates (BECs). In particular, using direct numerical simulations, we show that by switching-on a spatially inhomogeneous (step-like) change of the s-wave scattering length, it is possible to generate a controllable number of dark solitons in a quasi-one-dimensional BEC. A similar phenomenology is also found in the two-dimensional setting of 'disk-shaped' BECs but, as the solitons are subject to the snaking instability, they decay into vortex structures. A detailed investigation of how the parameters involved affect the emergence and evolution of solitons and vortices is provided.
Les Houches Summer School of Theoretical Physics : Session 72, Coherent Atomic Matter Waves
Westbrook, C; David, F; Coherent Atomic Matter Waves
2001-01-01
Progress in atomic physics has been so vigorous during the past decade that one is hard pressed to follow all the new developments. In the early 1990s the first atom interferometers opened a new field in which we have been able to use the wave nature of atoms to probe fundamental quantum me chanics questions as well as to make precision measurements. Coming fast on the heels of this development was the demonstration of Bose Einstein condensation in dilute atomic vapors which intensified research interest in studying the wave nature of matter, especially in a domain in which "macro scopic" quantum effects (vortices, stimulated scattering of atomic beams) are visible. At the same time there has been much progress in our understanding of the behavior of waves (notably electromagnetic) in complex media, both periodic and disordered. An obvious topic of speculation and probably of future research is whether any new insight or applications will develop if one examines the behavior of de Broglie waves in ana...
Matter-wave propagation in optical lattices: geometrical and flat-band effects
Metcalf, Mekena; Chern, Gia-Wei; Di Ventra, Massimiliano; Chien, Chih-Chun
2016-04-01
The geometry of optical lattices can be engineered, allowing the study of atomic transport along paths arranged in patterns that are otherwise difficult to probe in the solid state. A question feasible to atomic systems is related to the speed of matter-wave propagation as a function of the lattice geometry. To address this issue, we investigated, theoretically, the quantum transport of noninteracting and weakly-interacting ultracold fermionic atoms in several 2D optical lattice geometries. We find that the triangular lattice has a higher propagation velocity compared to the square lattice, and the cross-linked square lattice has an even faster propagation velocity. The increase results from the mixing of the momentum states which leads to different group velocities in quantum systems. Standard band theory provides an explanation and allows for a systematic way to search and design systems with controllable matter-wave propagation. Moreover, the presence of a flat band such as in a two-leg ladder geometry leads to a dynamical density discontinuity due to its localized atoms. Possible realizations of those dynamical phenomena are discussed.
Black holes and gravitational waves in models of minicharged dark matter
Cardoso, Vitor; Pani, Paolo; Ferrari, Valeria
2016-01-01
In viable models of minicharged dark matter, astrophysical black holes might be charged under a hidden $U(1)$ symmetry and are formally described by the same Kerr-Newman solution of Einstein-Maxwell theory. These objects are unique probes of minicharged dark matter and dark photons. We show that the recent gravitational-wave detection of a binary black-hole coalescence by aLIGO provides various observational bounds on the black hole's charge, regardless of its nature. The pre-merger inspiral phase can be used to constrain the dipolar emission of (ordinary and dark) photons, whereas the detection of the quasinormal modes set an upper limit on the final black hole's charge. By using a toy model of a point charge plunging into a Reissner-Nordstrom black hole, we also show that in dynamical processes the (hidden) electromagnetic quasinormal modes of the final object are excited to considerable amplitude in the gravitational-wave spectrum only when the black hole is nearly extremal. The coalescence produces a burs...
Christopher Candland, Labor, Democratization and Development in India and Pakistan
Lionel Baixas
2008-10-01
Full Text Available This book, by Christopher Candland, sets out to provide a documented analytical and empirical study of the linkages between organized labor, development, and democratization in India and Pakistan from the colonial period till date. It attempts to explain why sustained economic growth has not led to a significant diminution of poverty in either of these countries. The overall argument is that only rights-based organized labor unions can allow “the transformation of wealth into well-being”. Uni...
Barenboim, Gabriela, E-mail: Gabriela.Barenboim@uv.es; Park, Wan-Il, E-mail: Wanil.Park@uv.es
2016-08-10
We investigate the gravitational wave background from a first order phase transition in a matter-dominated universe, and show that it has a unique feature from which important information about the properties of the phase transition and thermal history of the universe can be easily extracted. Also, we discuss the inverse problem of such a gravitational wave background in view of the degeneracy among macroscopic parameters governing the signal.
Bouyer, P.
2015-12-01
Since its first demonstration in 1991, Atomic Interferometry (AI) has shown to be an extremely performing probe of inertial forces. More recently, AI has revealed sensitivities to acceleration or rotation competing with or even beating state-of-the art sensors based on other technologies. The high stability and accuracy of AI sensors relying on cold atoms is at the basis of several applications ranging from fundamental physics (e.g. tests of general relativity and measurements of fundamental constants), geophysics (gravimetry, gradiometry) and inertial navigation. We are currently building a large scale matter-wave detector which will open new applications in geoscience and fundamental physics. In contrast to standard AI based sensors, our matter-wave laser interferometer gravitation antenna (MIGA) exploits the superb seismic environment of a low noise underground laboratory. This new infrastructure is embedded into the LSBB underground laboratory, in France, ideally located away from major anthropogenic disturbances and benefitting from very low background noise. MIGA combines atom and laser interferometry techniques, manipulating an array of atomic ensembles distributed along the antenna to simultanously read out seismic effects, inertial effects and eventually the passage of a gravity wave. The first version uses a set of three atomic sensors placed along an optical cavity. The spatial resolution obtained with this configuration will enable the separation of the seismic, inertial and GW contributions. This technique will bring unprecedented sensitivities to gravity gradients variations and open new perspectives for sub Hertz gravity wave and geodesic detection. MIGA will provide measurements of gravity gradients variations limited only by the AI shot noise, which will allow sensitivities of about 10-13 s-2Hz-1/2@ 2Hz. This instrument will then be capable to spatially resolve 1 m3 of water a distances of about 100 m, which opens important potential applications
Slowly moving matter-wave gap soliton propagation in weak random nonlinear potential
Zhang Ming-Rui; Zhang Yong-Liang; Jiang Xun-Ya; Zi Jian
2008-01-01
We systematically investigate the motion of slowly moving matter-wave gap solitons in a nonlinear potential, produced by the weak random spatial variation of the atomic scattering length. With the weak randomness, we construct an effective-particle theory to study the motion of gap solitons. Based on the effective-particle theory, the effect of the randomness on gap solitous is obtained, and the motion of gap solitons is finally solved. Moreover, the analytic results for the general behaviours of gap soliton motion, such as the ensemble-average speed and the reflection probability depending on the weak randomness are obtained. We find that with the increase of the random strength the ensemble-average speed of gap solitons decreases slowly where the reduction is proportional to the variance of the weak randomness, and the reflection probability becomes larger. The theoretical results are in good agreement with the numerical simulations based on the Gross-Pitaevskii equation.
Observation of atomic speckle and Hanbury Brown-Twiss correlations in guided matter waves.
Dall, R G; Hodgman, S S; Manning, A G; Johnsson, M T; Baldwin, K G H; Truscott, A G
2011-01-01
Speckle patterns produced by multiple independent light sources are a manifestation of the coherence of the light field. Second-order correlations exhibited in phenomena such as photon bunching, termed the Hanbury Brown-Twiss effect, are a measure of quantum coherence. Here we observe for the first time atomic speckle produced by atoms transmitted through an optical waveguide, and link this to second-order correlations of the atomic arrival times. We show that multimode matter-wave guiding, which is directly analogous to multimode light guiding in optical fibres, produces a speckled transverse intensity pattern and atom bunching, whereas single-mode guiding of atoms that are output-coupled from a Bose-Einstein condensate yields a smooth intensity profile and a second-order correlation value of unity. Both first- and second-order coherence are important for applications requiring a fully coherent atomic source, such as squeezed-atom interferometry.
Evolution of Matter Wave Interference of Bose-Condensed Gas in a 1D Optical Lattice
XU Zhi-Jun; ZHANG Dong-Mei
2007-01-01
For a Bose-condensed gas in a combined potential consisting of an axially-symmetric harmonic magnetic trap and one-dimensional (1D) optical lattice, using the mean-field Gross-Pitaevskii (G-P) equation and the propagator method, we obtain the analytical result of the order parameter for matter wave interference at any time. The evolution of the interference pattern under a variation of the relative phase △φ between successive subcondensates trapped on an optical lattices is also studied. For △φ = π, the interference pattern is symmetric with two sharp peaks, which are symmetrically located on a straight line on both sides of a vacant central peak and moving apart from each other. This work is in agreement with available experimental results.
Matter-wave beam splitter on an atom chip for a portable atom-interferometer
Kim, S J; Gang, S T; Kim, J B
2016-01-01
We construct a matter-wave beam splitter using 87Rb Bose-Einstein condensate on an atom chip. Through the use of radio-frequency-induced double-well potentials, we were able to split a BEC into two clouds separated by distances ranging from 2.8 {\\mu}m to 57 {\\mu}m. Interference between these two freely expanding BECs has been observed. By varying the rf-field amplitude, frequency, or polarization, we investigate behaviors of the beam-splitter. From the perspective of practical use, our BEC manipulation system is suitable for application to interferometry since it is compact and the repetition rate is high due to the anodic bonded atom chip on the vacuum cell. The portable system occupies a volume of 0.5 m3 and operates at a repetition rate as high as ~0.2 Hz.
Matter-wave soliton bouncing on a reflecting surface under the effect of gravity
Benseghir, A.; Abdullah, W. A. T. Wan; Baizakov, B. B.; Abdullaev, F. Kh.
2014-08-01
The dynamics of a matter-wave soliton bouncing on the reflecting surface (atomic mirror) under the effect of gravity has been studied by analytical and numerical means. The analytical description is based on the variational approach. Resonant oscillations of the soliton's center of mass and width, induced by appropriate modulation of the atomic scattering length and the slope of the linear potential, are analyzed. In numerical experiments we observe the Fermi-type acceleration of the soliton when the vertical position of the reflecting surface is periodically varied in time. Analytical predictions are compared to the results of numerical simulations of the Gross-Pitaevskii equation and qualitative agreement between them is found.
Quantum reflection of bright solitary matter-waves from a narrow attractive potential
Marchant, A L; Yu, M M H; Rakonjac, A; Helm, J L; Polo, J; Weiss, C; Gardiner, S A; Cornish, S L
2015-01-01
We report the observation of quantum reflection from a narrow, attractive, potential using bright solitary matter-waves formed from a 85Rb Bose-Einstein condensate. We create narrow potentials using a tightly focused, red-detuned laser beam, and observe reflection of up to 25% of the atoms, along with the trapping of atoms at the position of the beam. We show that the observed reflected fraction is much larger than theoretical predictions for a narrow Gaussian potential well; a more detailed model of bright soliton propagation, accounting for the generic presence of small subsidiary intensity maxima in the red-detuned beam, suggests that these small intensity maxima are the cause of this enhanced reflection.
Escape of a vector matter-wave soliton from a parabolic trap
Bludov, Yuliy V.; García-Ñustes, Monica A.
2017-07-01
We show that a vector matter-wave soliton in a Bose-Einstein condensate (BEC) loaded into an optical lattice can escape from a trap formed by a parabolic potential, resembling a Hawking emission. The particle-antiparticle pair is emulated by a low-amplitude bright-bright soliton in a two-component BEC with effective masses of opposite signs. It is shown that the parabolic potential leads to a spatial separation of BEC components. One component with chemical potential in a semi-infinite gap exerts periodical oscillations, while the other BEC component, with negative effective mass, escapes from the trap. The mechanism of atom transfer from one BEC component to another by spatially periodic linear coupling term is also discussed.
Metamorfosi e inversioni ironiche da Christopher Marlowe a Edith Sitwell
Giovanna Silvani
2010-06-01
Full Text Available Il mio intervento si propone di analizzare le citazioni bibliche e classiche inserite da Christopher Marlowe nei suoi drammi, spesso con intenti ironici e dissacranti, specie nel Doctor Faustus e in The Jew of Malta, al fine di verificare gli scopi che si propone il drammaturgo con le distorsioni e le omissioni operate sui testi sacri da lui citati.Le potenzialità seminali della catena intertestuale sono testimoniate dalle citazioni rintracciabili in alcune poesie di Edith Sitwell, poetessa modernista, ispirate alla Seconda Guerra Mondiale e tratte dai drammi marloviani. Sono prestiti che ribadiscono che la Sitwell utilizza i meccanismi intertestuali conferendo alle parole “rubate” una nuova vitalità che conduce ad esiti intriganti e imprevedibili.This essay starts by examining the abundant Biblical references in Christopher Marlowe’s drama, and especially The Jew of Malta and Doctor Faustus. It particularly assesses the degree of fidelity of such references to their source text, as it throws light on the distortions and omissions by which the playwright modifies Holy Scripture to fit his own ends. Subsequently, the essay considers the poetical production of the Modernist author Edith Sitwell, who, in her compositions inspired by World War II, recovers and refashions some significant passages from Marlowe’s works. Indeed, Sitwell’s verse is a valuable instance of her remarkable skill in awarding new vitality and relevance to words and phrases which she extracts from the literary tradition in order to transform and update them.
The role of the wave function in the GRW matter density theory
Egg, Matthias [University of Lausanne (Switzerland)
2014-07-01
Every approach to quantum mechanics postulating some kind of primitive ontology (e.g., Bohmian particles, a mass density field or flash-like collapse events) faces the challenge of clarifying the ontological status of the wave function. More precisely, one needs to spell out in what sense the wave function ''governs'' the behaviour of the primitive ontology, such that the empirical predictions of standard quantum mechanics are recovered. For Bohmian mechanics, this challenge has been addressed in recent papers by Belot and Esfeld et al. In my talk, I do the same for the matter density version of the Ghirardi-Rimini-Weber theory (GRWm). Doing so will highlight relevant similarities and differences between Bohmian mechanics and GRWm. The differences are a crucial element in the evaluation of the relative strengths and weaknesses of the two approaches, while the similarities can shed light on general characteristics of the primitive ontology approach, as opposed to other interpretative approaches to quantum mechanics.
De Broglie's matter-waves are based on a logical bug
Giese, Albrecht
2016-07-01
The postulation of matter waves by Louis de Broglie in 1923 was one of the basic starting points in the development of quantum mechanics. However, his deduction contains a serious logical error. De Broglie deduced his central formula from considerations about the relativistic behaviour of a particle. He saw a conflict in the fact that a particle set into motion increases its internal frequency, f, according to E=h.f, whereas on the other hand its frequency has to decrease due to dilation. To solve this, he assigned a new ''de Broglie wave'' to a particle, which is related to the momentum of the particle. Scattering experiments seemed to confirm this approach. However, if such a scattering process is observed from a moving system, it turns out that the relationship between the wavelength and the momentum yields nonsensical results. - De Broglie's deduction is based on an incorrect understanding of relativity with respect to dilation. We show which results are achieved if a correct understanding is applied. And we show why, in a normal scattering experiment, de Broglie's incorrect formula nevertheless yields the expected results. We will further explain some of the impacts of this error on the equations of Schroedinger and Dirac, who used de Broglie's formula as a starting point. Heisenberg's uncertainty principle is also affected.
Dipolar matter-wave solitons in two-dimensional anisotropic discrete lattices
Chen, Huaiyu; Liu, Yan; Zhang, Qiang; Shi, Yuhan; Pang, Wei; Li, Yongyao
2016-05-01
We numerically demonstrate two-dimensional (2D) matter-wave solitons in the disk-shaped dipolar Bose-Einstein condensates (BECs) trapped in strongly anisotropic optical lattices (OLs) in a disk's plane. The considered OLs are square lattices which can be formed by interfering two pairs of plane waves with different intensities. The hopping rates of the condensates between two adjacent lattices in the orthogonal directions are different, which gives rise to a linearly anisotropic system. We find that when the polarized orientation of the dipoles is parallel to disk's plane with the same direction, the combined effects of the linearly anisotropy and the nonlocal nonlinear anisotropy strongly influence the formations, as well as the dynamics of the lattice solitons. Particularly, the isotropy-pattern solitons (IPSs) are found when these combined effects reach a balance. Motion, collision, and rotation of the IPSs are also studied in detail by means of systematic simulations. We further find that these IPSs can move freely in the 2D anisotropic discrete system, hence giving rise to an anisotropic effective mass. Four types of collisions between the IPSs are identified. By rotating an external magnetic field up to a critical angular velocity, the IPSs can still remain localized and play as a breather. Finally, the influences from the combined effects between the linear and the nonlocal nonlinear anisotropy with consideration of the contact and/or local nonlinearity are discussed too.
Statics and dynamics of a self-bound matter-wave quantum ball
Adhikari, S. K.
2017-02-01
We study the statics and dynamics of a stable, mobile, three-dimensional matter-wave spherical quantum ball created in the presence of an attractive two-body and a very small repulsive three-body interaction. The quantum ball can propagate with a constant velocity in any direction in free space and its stability under a small perturbation is established numerically and variationally. In frontal head-on and angular collisions at large velocities two quantum balls behave like quantum solitons. Such collision is found to be quasielastic and the quantum balls emerge after collision without any change of direction of motion and velocity and with practically no deformation in shape. When reflected by a hard impenetrable plane, the quantum ball bounces off like a wave obeying the law of reflection without any change of shape or speed. However, in a collision at small velocities two quantum balls coalesce to form a larger ball which we call a quantum-ball breather. We point out the similarity and difference between the collision of two quantum and classical balls. The present study is based on an analytic variational approximation and a full numerical solution of the mean-field Gross-Pitaevskii equation using the parameters of 7Li atoms.
Schmid, Manfred; Kroupa, Pavel
2014-08-01
We construct an idealised universe for didactic purposes. This universe is assumed to consist of absolute Euclidean space and to be filled with a classical medium which allows for sound waves. A known solution to the wave equation describing the dynamics of the medium is a standing spherical wave. Although this is a problem of classical mechanics, we demonstrate that the Lorentz transformation is required to generate a moving solution from the stationary one. Both solutions are here collectively referred to as "spherons". These spherons exhibit properties which have analogues in the physical description of matter with rest mass, among them de Broglie like phase waves and at the same time "relativistic" effects such as contraction and a speed limit. This leads to a theory of special relativity by assuming the point of view of an observer made of such spheronic "matter". The argument made here may thus be useful as a visualisation or didactic approach to the real universe, in which matter has wave-like properties and obeys the laws of special relativity.
Schmid, Manfred
2014-01-01
We construct an idealized universe for didactic purposes. This universe is assumed to consist of absolute Euclidean space and to be filled with a classical medium which allows for sound waves. A known solution to the wave equation describing the dynamics of the medium is a standing spherical wave. Although this is a problem of classical mechanics, we demonstrate that the Lorentz transformation is required to generate a moving solution from the stationary one. Both solutions are here collectively referred to as "spherons". These spherons exhibit properties which have analogues in the physical description of matter with rest mass, among them de Broglie like phase waves and at the same time "relativistic" effects such as contraction and a speed limit. This leads to a theory of special relativity by assuming the point of view of an observer made of such spheronic "matter". The argument made here may thus be useful as a visualisation or didactic approach to the real universe, in which matter has wave-like properti...
Bastos, Catarina
2016-01-01
In flat spacetime, quantum fluctuations in dark matter, as described as a Bose-Einstein condensate, are stable and display a relativistic Bogoliubov dispersion relation. In the weak gravitational field limit, both relativistic and nonrelativistic models self-gravitating dark matter suggest the formation of structures as the result of a dynamical (Jeans) instability. Here, we show that in the presence of spontaneous symmetry breaking of the dark matter field, the gravitational wave is damped for wave-lengths larger than the Jeans length. Such energy is converted to the Bogoliubov modes of the BEC that in their turn become unstable and grow, leading to the formation of structures even in the absence of expansion. Remarkably, this compensated attenuation/amplification mechanism is the signature of a discrete PT-symmetry-breaking of the system.
Semi-classical description of matter wave interferometers and hybrid quantum systems
Schneider, Mathias
2015-02-16
This work considers the semi-classical description of two applications involving cold atoms. This is, on one hand, the behavior of a BOSE-EINSTEIN condensate in hybrid systems, i.e. in contact with a microscopic object (carbon nanotubes, fullerenes, etc.). On the other, the evolution of phase space distributions in matter wave interferometers utilizing ray tracing methods was discussed. For describing condensates in hybrid systems, one can map the GROSS-PITAEVSKII equation, a differential equation in the complex-valued macroscopic wave function, onto a system of two differential equations in density and phase. Neglecting quantum dispersion, one obtains a semiclassical description which is easily modified to incorporate interactions between condensate and microscopical object. In our model, these interactions comprise attractive forces (CASIMIR-POLDER forces) and loss of condensed atoms due to inelastic collisions at the surface of the object. Our model exhibited the excitation of sound waves that are triggered by the object's rapid immersion, and spread across the condensate thereafter. Moreover, local particle loss leads to a shrinking of the bulk condensate. We showed that the total number of condensed particles is decreasing potentially in the beginning (large condensate, strong mean field interaction), while it decays exponentially in the long-time limit (small condensate, mean field inetraction negligible). For representing the physics of matter wave interferometers in phase space, we utilized the WIGNER function. In semi-classical approximation, which again consists in ignoring the quantum dispersion, this representation is subject to the same equation of motion as classical phase space distributions, i.e. the LIOUVILLE equation. This implies that time evolution of theWIGNER function follows a phase space flow that consists of classical trajectories (classical transport). This means, for calculating a time-evolved distribution, one has know the initial
Massive Primordial Black Holes as Dark Matter and their detection with Gravitational Waves
García-Bellido, Juan
2017-05-01
Massive Primordial Black Holes (MPBH) can be formed after inflation due to broad peaks in the primordial curvature power spectrum that collapse gravitationally during the radiation era, to form clusters of black holes that merge and increase in mass after recombination, generating today a broad mass-spectrum of black holes with masses ranging from 0.01 to 105 M⊙ . These MPBH could act as seeds for galaxies and quick-start structure formation, initiating reionization, forming galaxies at redshift z > 10 and clusters at z > 1. They may also be the seeds on which SMBH and IMBH form, by accreting gas onto them and forming the centers of galaxies and quasars at high redshift. They form at rest with zero spin and have negligible cross-section with ordinary matter. If there are enough of these MPBH, they could constitute the bulk of the Dark Matter today. Such PBH could be responsible for the observed fluctuations in the CIB and X-ray backgrounds. MPBH could be directly detected by the gravitational waves emitted when they merge to form more massive black holes, as recently reported by LIGO. Their continuous merging since recombination could have generated a stochastic background of gravitational waves that could eventually be detected by LISA and PTA. MPBH may actually be responsible for the unidentified point sources seen by Fermi, Magic and Chandra. Furthermore, the ejection of stars from shallow potential wells like those of Dwarf Spheroidals (DSph), via the gravitational slingshot effect, could be due to MPBH, thus alleviating the substructure and too-big-to-fail problems of standard collisionless CDM. Their mass distribution peaks at a few tens of M⊙ today, and could therefore be detected also with long-duration microlensing events, as well as by the anomalous motion of stars in the field of GAIA. Their presence as CDM in the Universe could be seen in the time-dilation of strong-lensing images of quasars. The hierarchical large scale structure behaviour of MPBH
Kengne, E; Lakhssassi, A
2015-03-01
We consider a lossless one-dimensional nonlinear discrete bi-inductance electrical transmission line made of N identical unit cells. When lattice effects are considered, we use the reductive perturbation method in the semidiscrete limit to show that the dynamics of modulated waves can be modeled by the classical nonlinear Schrödinger (CNLS) equation, which describes the modulational instability and the propagation of bright and dark solitons on a continuous-wave background. Our theoretical analysis based on the CNLS equation predicts either two or four frequency regions with different behavior concerning the modulational instability of a plane wave. With the help of the analytical solutions of the CNLS equation, we investigate analytically the effects of the linear capacitance CS on the dynamics of matter-wave solitons in the network. Our results reveal that the linear parameter CS can be used to manipulate the motion of bright, dark, and kink soliton in the network.
Statics and dynamics of a self-bound dipolar matter-wave droplet
Adhikari, S. K.
2017-02-01
We study the statics and dynamics of a stable, mobile, self-bound three-dimensional dipolar matter-wave droplet created in the presence of a tiny repulsive three-body interaction. In frontal collision with an impact parameter and in angular collision at large velocities along all directions two droplets behave like quantum solitons. Such a collision is found to be quasi elastic and the droplets emerge undeformed after collision without any change of velocity. However, in a collision at small velocities the axisymmeric dipolar interaction plays a significant role and the collision dynamics is sensitive to the direction of motion. For an encounter along the z direction at small velocities, two droplets, polarized along the z direction, coalesce to form a larger droplet—a droplet molecule. For an encounter along the x direction at small velocities, the same droplets stay apart and never meet each other due to the dipolar repulsion. The present study is based on an analytic variational approximation and a numerical solution of the mean-field Gross–Pitaevskii equation using the parameters of 52Cr atoms.
Gravitational waves as a probe of dark matter mini-spikes
Eda, Kazunari; Kuroyanagi, Sachiko; Silk, Joseph
2014-01-01
Recent studies show that an intermediate mass black hole (IMBH) may develop a dark matter (DM) mini-halo according to some BH formation scenarios. We consider a binary system composed of an IMBH surrounded by a DM mini-spike and a stellar mass object orbiting around the IMBH. The binary evolves due to gravitational pull and dynamical friction from the DM mini-spike and back-reaction from its gravitational wave (GW) radiation which can be detected by future space-borne GW experiments such as eLISA/NGO. We consider a single power-law model for the DM mini-spike which is assumed to consist of non-annihilating DM particles and demonstrate that an eLISA/NGO detection of GW from such a binary enables us to measure the DM mini-spike parameters very accurately. For instance, in our reference case originally advocated by Zhao and Silk (2005) and Bertone et al. (2005), we could determine the power-law index $\\alpha$ of the DM mini-spike radial profile with a 1 $\\sigma$ relative error of $\\pm 5\\times 10^{-6}$ for a GW s...
Constraining warm dark matter mass with cosmic reionization and gravitational wave
Tan, W W; Cheng, K S
2016-01-01
We constrain the warm dark matter (WDM) particle mass with the observations of cosmic reionization and CMB optical depth. We suggest that the GWs from stellar mass black holes (BHs) could give a further constraint on WDM particle mass for future observations. The star formation rates (SFRs) of Population I/II (Pop I/II) and Population III (Pop III) stars are also derived. If the metallicity of the universe have been enriched beyond the critical value of $Z_{\\rm crit}=10^{-3.5}Z_{\\odot}$, the star formation shift from Pop III to Pop I/II stars. Our results show that the SFRs are quite dependent on the WDM particle mass, especially at high redshifts. Combing with the reionization history and CMB optical depth derived from the recent \\emph{Planck} mission, we find that the current data requires the WDM particle mass in a narrow range of $1 < m_x < 3$ keV. Furthermore, we suggest that the stochastic gravitational wave background (SGWB) produced by stellar BHs could give a further constraint on the WDM parti...
Gravitational wave signatures of inflationary models from Primordial Black Hole dark matter
García-Bellido, Juan; Peloso, Marco; Unal, Caner
2017-09-01
Primordial Black Holes (PBH) could be the cold dark matter of the universe. They could have arisen from large (order one) curvature fluctuations produced during inflation that reentered the horizon in the radiation era. At reentry, these fluctuations source gravitational waves (GW) via second order anisotropic stresses. These GW, together with those (possibly) sourced during inflation by the same mechanism responsible for the large curvature fluctuations, constitute a primordial stochastic GW background (SGWB) that unavoidably accompanies the PBH formation. We study how the amplitude and the range of frequencies of this signal depend on the statistics (Gaussian versus χ2) of the primordial curvature fluctuations, and on the evolution of the PBH mass function due to accretion and merging. We then compare this signal with the sensitivity of present and future detectors, at PTA and LISA scales. We find that this SGWB will help to probe, or strongly constrain, the early universe mechanism of PBH production. The comparison between the peak mass of the PBH distribution and the peak frequency of this SGWB will provide important information on the merging and accretion evolution of the PBH mass distribution from their formation to the present era. Different assumptions on the statistics and on the PBH evolution also result in different amounts of CMB μ-distortions. Therefore the above results can be complemented by the detection (or the absence) of μ-distortions with an experiment such as PIXIE.
Dikande, Alain Moise; Ebobenow, Joseph
2010-01-01
A theoretical scheme for an experimental implementation involving bisolitonic matter waves from an attractive Bose-Einstein condensate, is considered within the framework of a non-perturbative approach to the associate Gross-Pitaevskii equation. The model consists of a single condensate subjected to an expulsive harmonic potential creating a double-condensate structure, and a gravitational potential that induces atomic exchanges between the two overlapping post condensates. Using a non-isospectral scattering transform method, exact expressions for the bright-matter-wave bisolitons are found in terms of double-lump envelopes with the co-propagating pulses displaying more or less pronounced differences in their widths and tails depending on the mass of atoms composing the condensate.
Song Chang-Sheng; Li Jing; Zong Feng-De
2012-01-01
An extended variation approach to describing the dynamic evolution of self-attractive Bose-Einstein condensates is developed.We consider bright matter-wave solitons in the presence of a parabolic magnetic potential and a timespace periodic optical lattice.The dynamics of condensates is shown to be well approximated by four coupled nonlinear differential equations.A noteworthy feature is that the extended variation approach gives a critical strength ratio to support multiple stable lattice sites for the condensate.We further examine the existence of the solitons and their stabilities at the multiple stable lattice sites. In this case,the analytical predictions of Bose-Einstein condensates variational dynamics are found to be in good agreement with numerical simulations.We then find a stable region for successful manipulating matter-wave solitons without collapse,which are dragged from an initial stationary to a prescribed position by a moving periodic optical lattice.
Lush, David C
2016-01-01
It is investigated whether the Planck-Einstein relation between the energy and frequency of light quanta, and the de Broglie wavelength of matter can be wholly or partially explained as consequences of the relativistic Doppler shift of electromagnetic fields caused by oscillating electric dipoles within the elementary particles constituting light and matter, and their electromagnetic interaction with similarly constituted particles. Assuming the oscillation is at the zitterbewegung frequency of the Dirac electron theory, the photon energy is found to be approximately half the value expected according to the Planck-Einstein relation. The relativistically Doppler shifted time-symmetric electromagnetic field due to the particle is found to have a superluminal phase velocity equal to that of the de Broglie matter wave, a group velocity equal to the particle velocity, and a wavelength of \\(h/p\\).
VERA M. FERNANDES-DE-LIMA
2001-09-01
Full Text Available The brain is an excitable media in which excitation waves propagate at several scales of time and space. ''One-dimensional'' action potentials (millisecond scale along the axon membrane, and spreading depression waves (seconds to minutes at the three dimensions of the gray matter neuropil (complex of interacting membranes are examples of excitation waves. In the retina, excitation waves have a prominent intrinsic optical signal (IOS. This optical signal is created by light scatter and has different components at the red and blue end of the spectrum. We could observe the wave onset in the retina, and measure the optical changes at the critical transition from quiescence to propagating wave. The results demonstrated the presence of fluctuations preceding propagation and suggested a phase transition. We have interpreted these results based on an extrapolation from Tasaki's experiments with action potentials and volume phase transitions of polymers. Thus, the scatter of red light appeared to be a volume phase transition in the extracellular matrix that was caused by the interactions between the cellular membrane cell coat and the extracellular sugar and protein complexes. If this hypothesis were correct, then forcing extracellular current flow should create a similar signal in another tissue, provided that this tissue was also transparent to light and with a similarly narrow extracellular space. This control tissue exists and it is the crystalline lens. We performed the experiments and confirmed the optical changes. Phase transitions in the extracellular polymers could be an important part of the long-range correlations found during wave propagation in central nervous tissue.O encéfalo é um meio excitável no qual ondas de excitação se propagam em várias escalas de tempo e espaço. Potenciais de axônios ''unidimensionais'' (escala de milisegundos ao longo da membrana axonal e ondas de depressão alastrante (segundos a minutos nas três dimens
Christopher Hill: uma visão sobre a liberdade
Caroline Oliveira Jung
2006-04-01
Full Text Available Neste trabalho discute-se a questão da liberdade, o que é ser livre no século XVI e XVII, em específico dentro da Revolução Inglesa. Para isso, toma-se como base o livro O mundo de ponta-cabeça: idéias radicais durante a Revolução Inglesa de 1640, de Christopher Hill, pois esse autor dá um outro enfoque à Revolução Inglesa, mostra-a de outro ponto de vista, o do povo, que foi parte fundamental para que essa revolução tomasse as proporções que tomou, sendo um marco para a história tanto inglesa quanto mundial. Também o capítulo “Acumulação primitiva” de O capital, de Karl Marx, que mostra as transformações do feudalismo para o capitalismo e como estas interferiram nos fatores que levaram à Revolução Inglesa.
Sounding Out Homer: Christopher Logue’s Acoustic Homer
Emily Greenwood
2009-10-01
Full Text Available Christopher Logue’s adaptations of Homer’s _Iliad_ go by the collective title of _War Music_, hinting at the importance of sound for Logue’s conception of the project. This article examines Logue’s Homer in the context of other contemporary translators of Homer who have all sought, in various ways, to produce translations that bring Homer to life. In Logue’s case, performance is a vital part of this enlivening, resulting in a poem with an intrinsic oral dimension, which is reproduced on the page via various typographical cues and reinforced by the poem’s performance history on radio and stage. In this essay the soundscape of Logue’s Homer is illustrated by a detailed case study of a single scene from Book 16 of the _Iliad_, in which the sound effects present in the Homeric simile are amplified. It considers the paradox of attributing aural fidelity to a free adaptation of Homer, before concluding that Logue’s adaptation can make us more attuned to the acoustic potential of Homer. Conversely, the tension between writing and oral genres inherent in Homeric epic can lead us to a better understanding of the relationship between the written and spoken word in Logue’s Homer.
The conquest of paradise or Christopher Columbus’s utopia
Vladimir Karanović
2014-12-01
Full Text Available The paper analyses the relationship between film and history based on the film 1492: Conquest of Paradise by Ridley Scott. It questions the importance of the context in which the movie with a historical theme is created and in that light its significance is interpreted. Based on the structural theory of myth, the article examines the elements of the mythic structure of Christopher Columbus’s voyage, relating this concept to Utopia. Special emphasis is placed on the importance of the first meeting or the clash between two cultures, which determines their future relations. According to the established theoretical and critical framework, the notions of paradise as well as the figure of the foreigner are questioned. The intention of this paper is to demonstrate that in Ridley Scott’s film history is much more complex and cannot be enclosed in platitudes and common places. Although it was not Scott’s intention to offer a counterfactual view of recorded history, and he does not question what might have happened in other circumstances, by introducing certain apocryphal elements and foretelling later historical events, we show that he is able to start a discussion on views on the process of discovery and conquest of America and especially about their meaning throughout history and their relationship with the present.
Granada, Miguel A; Jardine, Nicholas
2014-01-01
Christoph Rothmann's Discourse on the Comet of 1585 offers the first edition of the Latin treatise after it was published in 1619. It is accompanied by an English translation and a full introduction and commentary.
Zellweger : kusagil on ikka üks suurem plaan / Christoph Zellweger ; interv. K. M.
Zellweger, Christoph
2002-01-01
Šveitsi-austria päritolu, praegu Inglismaal elav ja töötav ehtekunstnik Christoph Zellweger endast, oma loomingust, mida tema tööd kajastavad, ehtekunsti väljavaadetest, implantaatidest, eesti ehetest jm.
Tunne Kelam - kolleeg ja sõber / Christopher Beazley, Elmar Bork, Ari Vatanen ...[jt.
2009-01-01
Euroopa Parlamendi väliskomisjoni liikmed Christopher Beazley, Elmar Bork, Ari Vatanen, Leedu Vabariigi president Valdas Adamkus, Euroopa Parlamendi asepresident Alejo Vidal-Quadras ja Euroopa Parlamendi president Hans-Gert Pöttering Tunne Kelamist
Zellweger : kusagil on ikka üks suurem plaan / Christoph Zellweger ; interv. K. M.
Zellweger, Christoph
2002-01-01
Šveitsi-austria päritolu, praegu Inglismaal elav ja töötav ehtekunstnik Christoph Zellweger endast, oma loomingust, mida tema tööd kajastavad, ehtekunsti väljavaadetest, implantaatidest, eesti ehetest jm.
Sõltumatud kodanikud otsustavad superriigi juhi saatuse / Christopher Kukk ; interv. Priit Pullerits
Kukk, Christopher
2008-01-01
Eesti päritolu Lääne-Connecticuti politoloogiaprofessor vastab küsimustele, mis puudutavad USA presidendivalimisi ja presidendikandidaatide Barack Obama ja John McCaini võimalusi. Vt. samas: Kes on Christopher Kukk?
Tunne Kelam - kolleeg ja sõber / Christopher Beazley, Elmar Bork, Ari Vatanen ...[jt.
2009-01-01
Euroopa Parlamendi väliskomisjoni liikmed Christopher Beazley, Elmar Bork, Ari Vatanen, Leedu Vabariigi president Valdas Adamkus, Euroopa Parlamendi asepresident Alejo Vidal-Quadras ja Euroopa Parlamendi president Hans-Gert Pöttering Tunne Kelamist
Sõltumatud kodanikud otsustavad superriigi juhi saatuse / Christopher Kukk ; interv. Priit Pullerits
Kukk, Christopher
2008-01-01
Eesti päritolu Lääne-Connecticuti politoloogiaprofessor vastab küsimustele, mis puudutavad USA presidendivalimisi ja presidendikandidaatide Barack Obama ja John McCaini võimalusi. Vt. samas: Kes on Christopher Kukk?
Collective transport for active matter run-and-tumble disk systems on a traveling-wave substrate
Sándor, Cs.; Libál, A.; Reichhardt, C.; Reichhardt, C. J. Olson
2017-01-01
We examine numerically the transport of an assembly of active run-and-tumble disks interacting with a traveling-wave substrate. We show that as a function of substrate strength, wave speed, disk activity, and disk density, a variety of dynamical phases arise that are correlated with the structure and net flux of disks. We find that there is a sharp transition into a state in which the disks are only partially coupled to the substrate and form a phase-separated cluster state. This transition is associated with a drop in the net disk flux, and it can occur as a function of the substrate speed, maximum substrate force, disk run time, and disk density. Since variation of the disk activity parameters produces different disk drift rates for a fixed traveling-wave speed on the substrate, the system we consider could be used as an efficient method for active matter species separation. Within the cluster phase, we find that in some regimes the motion of the cluster center of mass is in the opposite direction to that of the traveling wave, while when the maximum substrate force is increased, the cluster drifts in the direction of the traveling wave. This suggests that swarming or clustering motion can serve as a method by which an active system can collectively move against an external drift.
From Information to Experience: Christoph Schlingensief's Quiz 3000
Tara Forrest
2014-03-01
Full Text Available When German artist Christoph Schlingensief died in 2010 he had amassed an impressive body of work spanning a diverse range of fields, including film, television, theatre, art, radio, activism, and opera. Although he gained a certain notoriety for his early film and performance work, it was through his politically engaged re-enactment of a series of reality television programs that his public profile in Germany was cemented. This article focuses on the pilot episode of Quiz 3000 that was staged at the Volksbühne in 2002 and that was modelled closely on the popular reality format Who Wants to be a Millionaire? As Schlingensief has made clear in an interview with Alexander Kluge, his interest in re-enactment as a critical strategy is not driven by a desire for total verisimilitude, but by the inconsistencies that are generated in the re-enactment process that serve as catalysts for reflection and debate. In Quiz 3000 it is the nature of the questions posed to the contestants (such as: 'The rape of members of which minority group is, according to the German criminal code, less heavily penalized?' and 'How many conscientious objectors from Kurdistan have, since 2001, been tortured to death in Turkey after being deported by Germany?' that generates the inconsistency in question. Drawing on Walter Benjamin and Theodor Adorno's writings on information and experience, I argue that Quiz 3000 transforms the information-driven focus of television quiz shows into a source of experience for viewers and contestants alike by encouraging them to reflect on political issues and debates in an autonomous, affective, and meaningful way.
Christopher Hawkes and the International Summer Courses of Ampurias
Margarita Díaz-Andreu
2007-05-01
Full Text Available This article aims to provide an initial analysis of the early connections between Christopher Hawkes and Spanish archaeology in the context of his participation in two of the international summer courses in Ampurias in 1947 and 1950. The documentation used for this article comes mainly from the Pericot Archive in the Library of Catalonia, in which there are 43 letters from Hawkes to Pericot between 1940 and 1975. In addition, other correspondence in the British Museum and in the Ministry of Foreign Affairs will be mentioned. This study forms part of a larger project of recovering the memory of twentieth-century British-Spanish relations, of which a first phase has centred on the assessment of Gordon Childe’s contacts with Spain (Díaz-Andreu 1998; forthcoming–a; forthcoming–b. As in Gordon Childe’s case, all memory of Hawkes’ visits, and indeed of his relationships with Spanish archaeologists, has since been lost. Unfortunately, this situation is not exceptional: most of the links between Spanish archaeologists and British and American archaeologists in the twenty years around the Spanish Civil War have dropped out of archaeological memory. To the names mentioned in a recent seminar (Gordon Childe, Edward Thurlow Leeds, Eoin MacWhite, Hubert Savory (Armada Pita 2006, many others could be added. As this article will show, however, there were many contacts and these help to explain some developments in the archaeological thinking and practice of the participants involved in these exchanges, as well as some events in the international organisation of archaeology.
Constraining Warm Dark Matter Mass with Cosmic Reionization and Gravitational Waves
Tan, Wei-Wei; Wang, F. Y.; Cheng, K. S.
2016-09-01
We constrain the warm dark matter (WDM) particle mass with observations of cosmic reionization and CMB optical depth. We suggest that the gravitational waves (GWs) from stellar-mass black holes (BHs) could give a further constraint on WDM particle mass for future observations. The star formation rates (SFRs) of Population I/II (Pop I/II) and Population III (Pop III) stars are also derived. If the metallicity of the universe is enriched beyond the critical value of {Z}{{crit}}={10}-3.5 {Z}⊙ , the star formation shifts from Pop III to Pop I/II stars. Our results show that the SFRs are quite dependent on the WDM particle mass, especially at high redshifts. Combined with the reionization history and CMB optical depth derived from the recent Planck mission, we find that the current data require the WDM particle mass to be in a narrow range of 1 {{keV}}≲ {m}{{x}}≲ 3 {{keV}}. Furthermore, we suggest that the stochastic gravitational wave background (SGWB) produced by stellar BHs could give a further constraint on the WDM particle mass for future observations. For {m}{{x}}=3 {{keV}}, with Salpeter (Chabrier) initial mass function (IMF), the SGWB from Pop I/II BHs has a peak amplitude of {{{Ω }}}{{GW}}≈ 2.8× {10}-9 (5.0× {10}-9) at f=316{{Hz}}, while the GW radiation at f\\lt 10 Hz is seriously suppressed. For {m}{{x}}=1 {{keV}}, the SGWB peak amplitude is the same as that for {m}{{x}}=1 {{keV}}, but a little lower at low frequencies. Therefore, it is hard to constrain the WDM particle mass by the SGWB from Pop I/II BHs. To assess the detectability of the GW signal, we also calculate the signal-to-noise ratios (S/N), which are {{S}}/{{N}}=37.7 (66.5) and 27 (47.7) for {m}{{x}}=3 {{keV}} and {m}{{x}}=1 {{keV}} for the Einstein Telescope with Salpeter (Chabrier) IMF, respectively. The SGWB from Pop III BHs is very dependent on the WDM particle mass, the GW strength could be an order of magnitude different, and the frequency band could be two times different for {m
Unlocking the full potential of wave-matter nonlinear coupling in the epsilon-near-zero regime
Ciattoni, Alessandro; Marini, Andrea; Di Falco, Andrea; Faccio, Daniele; Scalora, Michael
2015-01-01
In recent years, unconventional metamaterial properties have triggered a revolution of electromagnetic research which has unveiled novel scenarios of wave-matter interaction. A very small dielectric permittivity is a leading example of such unusual features, since it produces an exotic static-like regime where the electromagnetic field is spatially slowly-varying over a physically large region. The so-called epsilon-near-zero metamaterials thus offer an ideal platform where to manipulate the inner details of the "stretched" field. Here we theoretically prove that a standard nonlinearity is able to operate such a manipulation to the point that even a thin slab produces a dramatic nonlinear pulse transformation, if the dielectric permittivity is very small within the field bandwidth. The predicted non-resonant releasing of full nonlinear coupling produced by the epsilon-near-zero condition does not resort to any field enhancement mechanisms and opens novel routes to exploiting matter nonlinearity for steering t...
Su, Shih-Wei; Lu, Zhen-Kai; Gou, Shih-Chuan; Liao, Wen-Te
2016-10-01
Cavity quantum electrodynamics (CQED) has played a central role in demonstrating the fundamental principles of the quantum world, and in particular those of atom-light interactions. Developing fast, dynamical and non-mechanical control over a CQED system is particularly desirable for controlling atomic dynamics and building future quantum networks at high speed. However conventional mirrors do not allow for such flexible and fast controls over their coupling to intracavity atoms mediated by photons. Here we theoretically investigate a novel all-optical CQED system composed of a binary Bose-Einstein condensate (BEC) sandwiched by two atomic ensembles. The highly tunable atomic dispersion of the CQED system enables the medium to act as a versatile, all-optically controlled atomic mirror that can be employed to manipulate the vacuum-induced diffraction of matter-wave superradiance. Our study illustrates a innovative all-optical element of atomtroics and sheds new light on controlling light-matter interactions.
宣恒农; 左苗
2011-01-01
We present three families of exact matter-wave soliton solutions for an effective one-dimension two- component Bose-Einstein condensates （BECs） with tunable interactions, harmonic potential and gain or loss term. We investigate the dynamics of bright-bright solitons, bright-dark solitons and dark-dark solitons for the time-dependent expulsive harmonic trap potential, periodically modulated harmonic trap potential, and kinklike modulated harmonic trap potential. Through the Feshbach resonance, these dynamics can be realized in experiments by suitable control of time-dependent trap parameters, atomic interactions, and interaction with thermal cloud.
Dynamics and Matter-Wave Solitons in Bose-Einstein Condensates with Two- and Three-Body Interactions
Jing Chen
2014-01-01
Full Text Available By means of similarity transformation, this paper proposes the matter-wave soliton solutions and dynamics of the variable coefficient cubic-quintic nonlinear Schrödinger equation arising from Bose-Einstein condensates with time-dependent two- and three-body interactions. It is found that, under the effect of time-dependent two- and three-body interaction and harmonic potential with time-dependent frequency, the density of atom condensates will gradually diminish and finally collapse.
The pump-probe coupling of matter wave packets to remote lattice states
Sherson, Jacob F; Park, Sung Jong; Pedersen, Poul Lindholm;
2012-01-01
containing a Bose–Einstein condensate. The evolution of these wave packets is monitored in situ and their six-photon reflection at a band gap is observed. In direct analogy with pump–probe spectroscopy, a probe pulse allows for the resonant de-excitation of the wave packet into states localized around...
Eda, Kazunari; Kuroyanagi, Sachiko; Silk, Joseph
2013-01-01
An intermediate mass black hole (IMBH) may have a dark matter (DM) mini-halo around it and develop a spiky structure within less than a parsec from the IMBH. When a stellar mass object is captured by the mini-halo, it eventually infalls into such an IMBH due to gravitational wave back reaction which in turn could be observed directly by future space-borne gravitational wave experiments such as eLISA/NGO. In this paper, we show that the GW detectability strongly depends on the radial profile of the DM distribution. So if the GW is detected, the power index, that is, the DM density distribution would be determined very accurately. The DM density distribution obtained would make it clear how the IMBH has evolved from a seed BH and whether the IMBH has experienced major mergers in the past. Unlike the gamma ray observations of DM annihilation, GW is just sensitive to the radial profile of the DM distribution and even to non-interacting DM. Hence the effect we demonstrate here can be used as a new and powerful pro...
Schive, Hsi-Yu; Broadhurst, Tom; Huang, Kuan-Wei
2015-01-01
The newly established luminosity functions of high-z galaxies at $4 \\lesssim z \\lesssim 10$ can provide a stringent check on dark matter models that aim to explain the core properties of dwarf galaxies. The cores of dwarf spheroidal galaxies are understood to be too large to be accounted for by free streaming of warm dark matter without overly suppressing the formation of such galaxies. Here we demonstrate with cosmological simulations that wave dark matter, $\\psi$DM, appropriate for light bosons such as axions, does not suffer this problem, given a boson mass of $m_{\\psi} \\ge 1.2 \\times 10^{-22}{\\,\\rm eV}$ ($2\\sigma$). In this case, the halo mass function is suppressed below $\\sim 10^{10}{\\,M_\\odot}$ at a level that is consistent with the high-z luminosity functions, while simultaneously generating the kpc-scale cores in dwarf galaxies arising from the solitonic ground state in $\\psi$DM. We demonstrate that the reionization history in this scenario is consistent with the Thomson optical depth recently report...
Goos-Hänchen-like shift of three-level matter wave incident on Raman beams
Duan, Zhenglu; Hu, Liyun; Xu, XueXiang; Liu, Cunjin
2014-07-01
When a three-level atomic wavepacket is obliquely incident on a "edium slab" consisting of two far-detuned laser beams, there exists lateral shift between reflection and incident points at the surface of a "medium slab", analogous to optical Goos-Hanchen effect. We evaluate lateral shifts for reflected and transmitted waves via expansion of reflection and transmission coefficients, in contrast to the stationary phase method. Results show that lateral shifts can be either positive or negative dependent on the incident angle and the atomic internal state. Interestingly, a giant lateral shift of transmitted wave with high transmission probability is observed, which is helpful to observe such lateral shifts experimentally. Different from the two-level atomic wave case, we find that quantum interference between different atomic states plays crucial role on the transmission intensity and corresponding lateral shifts.
INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Subsonic radiation waves in neon
Loseva, T. V.; Nemchinov, I. V.
1989-02-01
Numerical methods are used to investigate the propagation of plane subsonic radiation waves in neon from an obstacle in the direction opposite to the incident radiation of Nd and CO2 lasers. An analysis is made of the influence of the power density of the incident radiation (in the range 10-100 MW/cm2) and of the initial density of neon (beginning from the normal valuep ρ0 up to 10ρ0) on the various characteristics of subsonic radiation waves. It is shown that waves traveling in neon can provide an effective source of radiation with a continuous spectrum and an efficiency of ~ 12-27% in the ultraviolet range (with a characteristic photon energy ~ 5-10 eV).
High frequency surface acoustic wave resonator-based sensor for particulate matter detection
Thomas, Sanju; Cole, Marina; Villa-López, Farah Helue; Gardner, J. W.
2016-01-01
This paper describes the characterization of high frequency Surface Acoustic Wave Resonator-based (SAWR) sensors, for the detection of micron and sub-micron sized particles. The sensor comprises two 262 MHz ST-cut quartz based Rayleigh wave SAWRs where one is used for particle detection and the other as a reference. Electro-acoustic detection of different sized particles shows a strong relationship between mass sensitivity (Δf/Δm) and particle diameter (Dp). This enables frequency-dependent S...
Decay of Langmuir wave in dense plasmas and warm dense matter
Son, S; Moon, Sung Joon
2010-01-01
The decays of the Langmuir waves in dense plasmas are computed using the dielectric function theory widely used in the solid state physics. Four cases are considered: a classical plasma, a Maxwellian plasma, a degenerate quantum plasma, and a partially degenerate plasma. The result is considerably different from the conventional Landau damping theory.
Snelder, Marieke
2015-01-01
The main focus of this thesis is to understand the correlations present at the s-wave/three-dimensional topological insulator interface both theoretically and experimentally. In the future, devices containing these kind of interfaces can be used to create and manipulate a Majorana zero-energy mode w
Understanding the core-halo relation of quantum wave dark matter from 3D simulations.
Schive, Hsi-Yu; Liao, Ming-Hsuan; Woo, Tak-Pong; Wong, Shing-Kwong; Chiueh, Tzihong; Broadhurst, Tom; Hwang, W-Y Pauchy
2014-12-31
We examine the nonlinear structure of gravitationally collapsed objects that form in our simulations of wavelike cold dark matter, described by the Schrödinger-Poisson (SP) equation with a particle mass ∼10(-22) eV. A distinct gravitationally self-bound solitonic core is found at the center of every halo, with a profile quite different from cores modeled in the warm or self-interacting dark matter scenarios. Furthermore, we show that each solitonic core is surrounded by an extended halo composed of large fluctuating dark matter granules which modulate the halo density on a scale comparable to the diameter of the solitonic core. The scaling symmetry of the SP equation and the uncertainty principle tightly relate the core mass to the halo specific energy, which, in the context of cosmological structure formation, leads to a simple scaling between core mass (Mc) and halo mass (Mh), Mc∝a(-1/2)Mh(1/3), where a is the cosmic scale factor. We verify this scaling relation by (i) examining the internal structure of a statistical sample of virialized halos that form in our 3D cosmological simulations and by (ii) merging multiple solitons to create individual virialized objects. Sufficient simulation resolution is achieved by adaptive mesh refinement and graphic processing units acceleration. From this scaling relation, present dwarf satellite galaxies are predicted to have kiloparsec-sized cores and a minimum mass of ∼10(8)M⊙, capable of solving the small-scale controversies in the cold dark matter model. Moreover, galaxies of 2×10(12)M⊙ at z=8 should have massive solitonic cores of ∼2×10(9)M⊙ within ∼60 pc. Such cores can provide a favorable local environment for funneling the gas that leads to the prompt formation of early stellar spheroids and quasars.
Chala, Mikael; Sobolev, Ivan
2016-01-01
A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite Higgs version of this scenario, based on the coset $SO(7)/SO(6)$. We show that by embedding the elementary fermions in appropriate representations of $SO(7)$, all dominant interactions are described by only three free effective parameters. Within the model dependencies of the embedding, the theory predicts one of the singlets to be stable and responsible for the observed dark matter abundance. At the same time, the second singlet introduces new $CP$-violation phases and triggers a strong first-order EWPT, making electroweak baryogenesis feasible. It turns out that this scenario does not conflict with current observations and it is promising for solving the dark matter and baryon asymmetry puzzles. The tight predictions of the model will be accessible at the forthcoming dark ...
Denkmayr, Tobias; Geppert, Hermann; Lemmel, Hartmut; Waegell, Mordecai; Dressel, Justin; Hasegawa, Yuji; Sponar, Stephan
2017-01-01
A method was recently proposed and experimentally realized for characterizing a quantum state by directly measuring its complex probability amplitudes in a particular basis using so-called weak values. Recently, Vallone and Dequal [Phys. Rev. Lett. 116, 040502 (2016), 10.1103/PhysRevLett.116.040502] showed theoretically that weak measurements are not a necessary condition to determine the weak value. Here, we report a measurement scheme used in a matter-wave interferometric experiment in which the neutron path system's quantum state was characterized via direct measurements, using both strong and weak interactions. Experimental evidence is given that strong interactions outperform weak ones for tomographic accuracy. Our results are not limited to neutron interferometry, but can be used in a wide range of quantum systems.
Nematollahi, Delaram; Zhang, Qimin; Altermatt, Joseph; Zhong, Shan; Goodman, Matthew; Bhagat, Anita; Schwettmann, Arne
2016-05-01
We present our apparatus designed to study matter-wave quantum optics in spin space, including our recently finished vacuum system and laser systems. Microwave-dressed spin-exchange collisions in a sodium spinor Bose-Einstein condensate provide a precisely controllable nonlinear interaction that generates squeezing and acts as a source of entanglement. As a consequence of this entanglement between atoms with magnetic quantum numbers m = +1 and m = -1, the noise of population measurements can be reduced below the shot noise. Versatile microwave pulse sequences will be used to implement an interferometer, a phase-sensitive amplifier and other devices. With an added ion detector to detect Rydberg atoms via pulsed-field ionization, we plan to study the effect of Rydberg excitations on the spin evolution of the ultracold gas.
Review of Matters Related to the Death of Hospitalman (HN) Christopher Purcell, U.S. Navy
2010-10-27
Building 731, Room 9A (Building 731 is a two-story condominium with 10 units configured to house two sailors per unit.). About a minute later, the...determination of the qualifications of candidates for employment, entrance on duty, advancement, or promotion; (c) computer software , the release of which... software must be closely examined to ensure a circumvention possibility exists. (b)(5) “Inter-agency or intra-agency memoranda or letters which would not
On p-Wave Pairing Superconductivity under Cubic Symmetry : Condensed Matter and Statistical Physics
Masa-aki, OZAKI; Kazushige, MACHIDA; Tetsuo, OHMI; Department of Physics, Kyoto University
1985-01-01
A group theoretical classification of p-wave pairing superconducting states is made for a system with cubic crystalline symmetry in the absence of the spin-orbit coupling. The 15 inert p-pairing states which make the Ginzburg-Landau free energy stationary are enumerated and characterized, indicating that the energy gap vanishes along lines on the Fermi surface in some of those states. This is contrasted with the strong spin-orbit coupling case by others.
Goos-Hanchen-like shift of three-level matter wave incident on Raman beams
Duan, Zhenglu; Hu, Liyun; Xu, XueXiang; Liu, Cunjin
2013-01-01
When a three-level atomic wavepacket is obliquely incident on a "edium slab" consisting of two far-detuned laser beams, there exists lateral shift between reflection and incident points at the surface of a "medium slab", analogous to optical Goos-Hanchen effect. We evaluate lateral shifts for reflected and transmitted waves via expansion of reflection and transmission coefficients, in contrast to the stationary phase method. Results show that lateral shifts can be either positive or negative ...
The influence of emerging administrative scientists: an interview with Dr Christopher Friese.
Friese, Christopher; Adams, Jeffrey M
2014-02-01
This department highlights emerging nursing leaders who have demonstrated great work and much potential in advancing innovation and patient care leadership in practice, policy, research, education, and theory. This interview profiles Christopher Friese, PhD, RN, AOCN, FAAN, assistant professor, University of Michigan School of Nursing.
Conflito de gerações: O expressionismo e Christoph Meckel
Claudia Dornbusch
1997-11-01
Full Text Available In diesem Artikel geht es darum, Charakteristika des deutschen Expressionismus und ihre Varianten in der deutschen Gegenwarsliteratur nachzuweisen. Unter dem Gesichtspunkt des Generationenkonflikts wird das 1980 veröffentlichte Werk Suchbild über meinen Vater von Christoph Meckel untersucht.
Etienne Wamba; Timoléon C. Kofané; Alidou Mohamadou
2012-01-01
We construct,through a further extension of the tanh-function method,the matter-wave solutions of Bose-Einstein condensates (BECs) with a three-body interaction.The BECs are trapped in a potential comprising the linear magnetic and the time-dependent laser fields.The exact solutions obtained include soliton solutions,such as kink and antikink as well as bright,dark,multisolitonic modulated waves.We realize that the motion and the shape of the solitary wave can be manipulated by controlling the strengths of the fields.
Farghaly, Othman A; Ghandour, M A
2005-03-01
The application of square-wave voltammetry (SWV) for the determination of eight elements viz. Cd(II), Pb(II), Cu(II), Zn(II), Co(II), Ni(II), Cr(VI), and Mo(VI) in soil and indoor-airborne particulate matter has been examined and optimized. The cathodic and anodic types of the SWV technique were examined for the detection of these metal ions. It was found that the square-wave anodic stripping voltammetry is the conventional technique for the determination of Zn(II), Cd(II), Pb(II), and Cu(II), but square-wave adsorptive cathodic stripping voltammetric method is used for the determination of Co(II), Ni(II), Mo(VI) and Cr(VI). Various experimental parameters, which influenced the response of the mercury film electrode to these metal ions, were optimized. The detection limits of these metal ions were 0.03, 0.4, 0.04, 0.1, 0.15, 0.05, 0.2, and 3.2 microg/kg for Cd(II), Pb(II), Cu(II), Zn(II), Co(II), Ni(II), Cr(VI), and Mo(VI), respectively, with very good accuracy (standard deviation is below 2%). Interference from coexisting ions was successfully investigated. A comparison of analytical data for analyzing real samples was carried out between the SWV method and the graphite furnace atomic absorption spectrophotometric (GFAAS) method. By the standard addition method, the recoveries were 96.6-104% with SD of 0.75-2.5%. The great advantage of SWV is the simplicity, selectivity, sensitivity, and shortening analysis time over the GFAAS method.
Comparison between two models of absorption of matter waves by a thin time-dependent barrier
Barbier, Maximilien; Beau, Mathieu; Goussev, Arseni
2015-11-01
We report a quantitative, analytical, and numerical comparison between two models of the interaction of a nonrelativistic quantum particle with a thin time-dependent absorbing barrier. The first model represents the barrier by a set of time-dependent discontinuous matching conditions, which are closely related to Kottler boundary conditions used in stationary-wave optics as a mathematical basis for Kirchhoff diffraction theory. The second model mimics the absorbing barrier with an off-diagonal δ potential with a time-dependent amplitude. We show that the two models of absorption agree in their predictions in a semiclassical regime, the regime readily accessible in modern experiments with ultracold atoms.
Gravitational waves in dynamical spacetimes with matter content in the Fully Constrained Formulation
Cordero-Carrión, Isabel; Ibáñez, José María
2011-01-01
The Fully Constrained Formulation (FCF) of General Relativity is a novel framework introduced as an alternative to the hyperbolic formulations traditionally used in numerical relativity. The FCF equations form a hybrid elliptic-hyperbolic system of equations including explicitly the constraints. We present an implicit-explicit numerical algorithm to solve the hyperbolic part, whereas the elliptic sector shares the form and properties with the well known Conformally Flat Condition (CFC) approximation. We show the stability andconvergence properties of the numerical scheme with numerical simulations of vacuum solutions. We have performed the first numerical evolutions of the coupled system of hydrodynamics and Einstein equations within FCF. As a proof of principle of the viability of the formalism, we present 2D axisymmetric simulations of an oscillating neutron star. In order to simplify the analysis we have neglected the back-reaction of the gravitational waves into the dynamics, which is small (<2 %) for ...
Schematic way to find solution of the outcoupled matter wave with a source term
Prayitno, T. B. [Physics Department, Faculty of Mathematics and Natural Science, Universitas Negeri Jakarta, Jl. Pemuda Rawamangun No. 10, Jakarta, 13220 (Indonesia)
2013-09-09
We propose a schematic way to obtain solution of the outcoupled atom laser beam wave function in the presence of a source term where the beam is influenced by gravity. In this case, we only focus on the external potentials inside the region of Bose-Einstein condensate that are generated by electromagnetic source and gravity. Since the evolution of the atom laser beam can be portrayed through the ordinary Schrödinger equation with a source, we are allowed to express the general solution as the superposition of the homogeneous solution and particular solution. With the given external potentials and ansatz solutions, we attain that the obtained energy depends on the parameter constituting to the ratio between the longitudinal frequency and transverse frequency.
Geiger, R; Bertoldi, A; Canuel, B; Chaibi, W; Danquigny, C; Dutta, I; Fang, B; Gaffet, S; Gillot, J; Holleville, D; Landragin, A; Merzougui, M; Riou, I; Savoie, D; Bouyer, P
2015-01-01
The MIGA project aims at demonstrating precision measurements of gravity with cold atom sensors in a large scale instrument and at studying the associated powerful applications in geosciences and fundamental physics. The firt stage of the project (2013-2018) will consist in building a 300-meter long optical cavity to interrogate atom interferometers and will be based at the low noise underground laboratory LSBB based in Rustrel, France. The second stage of the project (2018-2023) will be dedicated to science runs and data analyses in order to probe the spatio-temporal structure of the local gravity field of the LSBB region, which represents a generic site of hydrological interest. MIGA will also assess future potential applications of atom interferometry to gravitational wave detection in the frequency band 0.1-10 Hz hardly covered by future long baseline optical interferometers. This paper presents the main objectives of the project, the status of the construction of the instrument and the motivation for the...
The collapse of the wave function in the joint metric-matter quantization for inflation
Diez-Tejedor, Alberto; Sudarsky, Daniel
2011-01-01
It has been argued that the standard inflationary scenario suffers from a serious deficiency as a model for the origin of the seeds of cosmic structure: it can not truly account for the transition from an early homogeneous and isotropic stage to another one lacking such symmetries. The issue has often been thought as a standard instance of the "quantum measurement problem", but as has been recently argued by some of us the situation reaches a critical level in the cosmological context of interest here. This has lead to a proposal in which the standard paradigm is supplemented by a hypothesis concerning the self-induced dynamical collapse of the wave function, as representing the physical mechanism through which such change of symmetry is brought forth. This proposal was formulated within the context of semiclassical gravity. Here we investigate an alternative realization of such idea implemented directly within the standard analysis in terms of a quantum field jointly describing the inflaton and metric pertur...
Effective equations for matter-wave gap solitons in higher-order transversal states.
Mateo, A Muñoz; Delgado, V
2013-10-01
We demonstrate that an important class of nonlinear stationary solutions of the three-dimensional (3D) Gross-Pitaevskii equation (GPE) exhibiting nontrivial transversal configurations can be found and characterized in terms of an effective one-dimensional (1D) model. Using a variational approach we derive effective equations of lower dimensionality for BECs in (m,n(r)) transversal states (states featuring a central vortex of charge m as well as n(r) concentric zero-density rings at every z plane) which provides us with a good approximate solution of the original 3D problem. Since the specifics of the transversal dynamics can be absorbed in the renormalization of a couple of parameters, the functional form of the equations obtained is universal. The model proposed finds its principal application in the study of the existence and classification of 3D gap solitons supported by 1D optical lattices, where in addition to providing a good estimate for the 3D wave functions it is able to make very good predictions for the μ(N) curves characterizing the different fundamental families. We have corroborated the validity of our model by comparing its predictions with those from the exact numerical solution of the full 3D GPE.
Li, Bohua; Shapiro, Paul R.; Rindler-Daller, Tanja
2017-01-01
We consider an alternative to WIMP cold dark matter (CDM), ultralight bosonic dark matter (m≥10-22 eV) described by a complex scalar field (SFDM), of which the comoving particle number density is conserved after particle production during standard reheating (w=p/ρ=0). In a ΛSFDM universe, SFDM starts relativistic, evolving from stiff (w=1) to radiation-like (w=1/3), before becoming nonrelativistic at late times (w=0). Thus, before the familiar radiation-dominated phase, there is an even earlier phase of stiff-SFDM-domination, during which the expansion rate is higher than in ΛCDM. The transitions between these phases, determined by SFDM particle mass m, and coupling strength λ, of a quartic self-interaction, are therefore constrained by cosmological observables, particularly Neff, the effective number of neutrino species during BBN, and zeq, the redshift of matter-radiation equality. Furthermore, since the homogeneous energy density contributed by the stochastic gravitational wave background (SGWB) from inflation is amplified during the stiff phase, relative to the other components, the SGWB can contribute a radiation-like component large enough to affect these observables. This same amplification makes possible detection of this SGWB at high frequencies by current laser interferometer experiments, e.g., aLIGO/Virgo, eLISA. For SFDM particle parameters that satisfy these cosmological constraints, the amplified SGWB is detectable by aLIGO, for values of tensor-to-scalar ratio r currently allowed by CMB polarization measurements, for a broad range of possible reheat temperatures Tre. For a given r, if SFDM parameters marginally satisfy cosmological constraints (maximizing total SGWB energy density), the SGWB is maximally detectable when modes that reenter the horizon when reheating ends have frequencies in the 10-50 Hz aLIGO band today. For example, if r=0.01, the maximally detectable model for (λ/(mc2)2, m)=(10-18 eV-1cm3, 8×10-20 eV) has Tre=104 GeV, for
Arqueologia da memória: reflexões a partir de Christoph Türcke
Marcela Lopes Gomes
2015-01-01
Full Text Available This article discusses the genesis of memory in archaeology of mental processes from the ref lections developed by german philosopher Christoph Türcke in his work Philosophie des Traums (Original in German, a. This is a study that used the methodological feature of literature research. It discusses the emerging of memory as an attempt to release the tormentors stimuli through the process of compulsion to traumatic repetition, considered the only genuinely human drive by Türcke ( a.
Uus linnaökoloogia = New Urban Ecology / Christopher Moller ; interv. Triin Ojari
Moller, Christopher
2005-01-01
Arhitekt Christopher Moller (sünd. 1961, Uus-Meremaa) rajas 1997. a. koos Burton Hamfelti (Kanada), Jonathan Woodroffe'i ja Dominic Papaga (Inglismaa) Amsterdamis büroo S333. Büroo lähenemisest linnaplaneerimisele, Europani võidutöö järgi valminud Groningeni elamukompleksist Schots 1+2, Nieuw-Vennepi linnakeskuse projektist (2000-), kvaliteetruumist, linnaökoloogiast, Tallinna ja siinsete arhitektide võimalustest jm. 7 ill
Uus linnaökoloogia = New Urban Ecology / Christopher Moller ; interv. Triin Ojari
Moller, Christopher
2005-01-01
Arhitekt Christopher Moller (sünd. 1961, Uus-Meremaa) rajas 1997. a. koos Burton Hamfelti (Kanada), Jonathan Woodroffe'i ja Dominic Papaga (Inglismaa) Amsterdamis büroo S333. Büroo lähenemisest linnaplaneerimisele, Europani võidutöö järgi valminud Groningeni elamukompleksist Schots 1+2, Nieuw-Vennepi linnakeskuse projektist (2000-), kvaliteetruumist, linnaökoloogiast, Tallinna ja siinsete arhitektide võimalustest jm. 7 ill
Kudriavtcev, Iurii
2015-01-01
We explore the possibility to give a classical explanation to the specifics and physical sense of de Broglie matter waves when studying the microparticle as an object of non zero size, from the point of view of the special theory of relativity. We show that the particularities of de Broglie matter waves and the results of the experimental verifications of Bell inequalities for the pairs of entangled photons are naturally interpreted as the results of implementation of the conclusions of the special theory of relativity to the microparticles. We conclude that it is appropriate to go back to the search of the new means of realistic description of the nature proposed by Einstein and his realistic worldview that states that the world studied by the science is real and every part of it at any moment of time has objective physical characteristics.
Ibsen, Lars Bo
2008-01-01
Estimates for the amount of potential wave energy in the world range from 1-10 TW. The World Energy Council estimates that a potential 2TW of energy is available from the world’s oceans, which is the equivalent of twice the world’s electricity production. Whilst the recoverable resource is many t...
Mintz, Stephan; Perlmutter, Arnold; Neutrino Mass, Dark Matter and Gravitational Waves, Condensation of Atoms and Monopoles, Light-cone Quantization : Orbis Scientiae '96
1996-01-01
The International Conference, Orbis Scientiae 1996, focused on the topics: The Neutrino Mass, Light Cone Quantization, Monopole Condensation, Dark Matter, and Gravitational Waves which we have adopted as the title of these proceedings. Was there any exciting news at the conference? Maybe, it depends on who answers the question. There was an almost unanimous agreement on the overall success of the conference as was evidenced by the fact that in the after-dinner remarks by one of us (BNK) the suggestion of organizing the conference on a biannual basis was presented but not accepted: the participants wanted the continuation of the tradition to convene annually. We shall, of course, comply. The expected observation of gravitational waves will constitute the most exciting vindication of Einstein's general relativity. This subject is attracting the attention of the experimentalists and theorists alike. We hope that by the first decade of the third millennium or earlier, gravitational waves will be detected,...
M. I. Baranov
2016-11-01
Full Text Available Purpose. Implementation of brief analytical review of the basic distinguished scientific achievements of the world scientists-physicists in area of discovery and study of quantum-wave nature of physical processes and phenomena flowing in the microscopic world of circumferential people matter. Methodology. Scientific methods of collection, analysis and analytical treatment of scientific and technical information in area of theoretical and experimental physics, devoted the results of researches| of quantum and physical processes flowing in nature on atomic and subatomic levels. Results. The brief scientific and technical review of the basic scientific discovery and achievements of scientists-physicists is resulted in area of structure of atom of matter, generation, radiation, distribution and absorption of physical bodies of short-wave hertzian waves, indicative on a dominating role in the microscopic financial world of positions and conformities to the law of wave (by quantum mechanics, carrying especially probabilistic character a microstructure. Originality. Systematization is executed with exposition in the short concentrated form| of the known materials| on the quantum theory (electromagnetic of caloradiance, quantum theory of atom, electronic waves, quantum theory of actinoelectricity, quantum statistics of microparticless, quantum theory of the phenomenon superfluidity of liquid helium, quantum electronics and quantum-wave nature of drift of lone electrons in the metal of explorers with an electric current. Practical value. Popularization and deepening of fundamental physical and technical knowledges for students and engineer and technical specialists in area of classic and quantum physics, extending their scientific range of interests, and also support a further scientific study by them surrounding nature and to development of scientific and technical progress in society.
Between Copernicus and Galileo Christoph Clavius and the Collapse of Ptolemaic Cosmology
Lattis, James M
1994-01-01
Between Copernicus and Galileo is the story of Christoph Clavius, the Jesuit astronomer and teacher whose work helped set the standards by which Galileo's famous claims appeared so radical, and whose teachings guided the intellectual and scientific agenda of the Church in the central years of the Scientific Revolution. Though relatively unknown today, Clavius was enormously influential throughout Europe in the late sixteenth and early seventeenth centuries through his astronomy books—the standard texts used in many colleges and universities, and the tools with which Descartes, Gassendi, and Me
Christopher R. Fee & David A. Leeming. Gods, Heroes, and Kings. The Battle for Mythic Britain
Sophie ALATORRE
2006-06-01
Full Text Available A reassessment of British mythology has long been overdue, and Gods, Heroes and Kings is to be regarded as a stimulating contribution which helps to situate Anglo-Saxon tales in the mainstream of Medieval literature. Myths, pagan and Judeo-Christian beliefs, classical narratives: such vast material forms the backcloth Christopher F. Fee and David A. Leeming have undertaken to explore, thanks to an erudite comparative approach. Obviously, their book first aims at giving readers a new image of ...
Christopher E. Forth et Bertrand Taithe (dir, French Masculinities: History, Culture and Politics
Régis Revenin
2007-11-01
Full Text Available Cet ouvrage collectif, dirigé par Christopher E. Forth, historien à l’Australian National University à Canberra [Australie], et par Bertrand Taithe, professeur d’histoire culturelle à l’Université de Manchester [Royaume-Uni], offre une très intéressante contribution, en langue anglaise, à l’histoire du genre en France, particulièrement à l’histoire des hommes et des masculinités à l’époque contemporaine.L’ouvrage propose une très riche introduction sous la plume des deux directeurs d’ouvrage,...
TRADITIONS OF AVANT-GARDE SHOWN IN THE PERFORMANCES BY CHRISTOPH MARTHALER
Maryna Ivanovna Khudiakova
2015-01-01
Full Text Available The purpose of this paper was examining the way traditions and forms of avant-garde in dramatic art, in particular Expressionism and Dada, as well as elements typical of the Theater of the Absurd, have manifested themselves in the work pieces by the contemporary stage director from Switzerland Christoph Marthaler.The paper carried out a theater expert review of Christoph Marthaler’s performances of the Swiss period, as «Stägeli uf, Stägeli ab, juhee!», «Indeed», «Faust. Ein subjektive Tragödie», «ХХ Century’ Blues», that enabled the spectator’s judging from the creative personality of Marthaler, his outlook on the world and reflection of various issues of time. These performances were also considered to be of the most successful Marthaler’ performances in Switzerland having fully traced his unique stage director’ style. The study revealed the mainstream topic of each performance, which consisted of director’s reflections about loneliness of a contemporary human being, and reference to avant-garde’ forms converted these reflections into the stage play.
Simulator-Based Air Medical Training Program Christoph Life: From Concept to Course.
Winkelmann, Marcel; Friedrich, Lars; Schröter, Christian; Flemming, Andreas; Eismann, Hendrik; Sieg, Lion; Mommsen, Philipp; Krettek, Christian; Zeckey, Christian
2016-01-01
Christoph Life is a simulator-based air medical training program and a new and innovative educational concept. Participants pass different scenarios with a fully equipped and movable helicopter simulator. Main focuses of the program are crew resource management (CRM) elements and team training. Information about expectations end effectiveness of the training is sparse. During a 2-day training, participants learn CRM basics and complete various emergency medical scenarios. For evaluation, we used an anonymous questionnaire either with polar questions or a 6-coded psychometric Likert scale. The Wilcoxon test was used for statistical analysis. The significance level was set at P CRM basics (3.5 ± 1.2 vs. 5.4 ± 0.7, P benefit for the participants' nontechnical skills. Copyright © 2016 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.
Coogan, Tom
2012-01-01
This article uses theory on disability, embodiment and language to explore the production, context and presentation of two pieces of life-writing by Christopher Nolan. It examines Nolan's unusual use of language and form in his presentations of an experience of disability, and considers its literary and political significance. Consideration is…
Lillejord, Jebadiah Serril
2013-01-01
The purpose of this study is to investigate to what extent contemporary high school world history textbooks portray Christopher Columbus, Hernán Cortés, and Francisco Pizarro within the context of being "sacred," "profane," or someplace in between. To evaluate for existence of content bias this study employed qualitative…
Coogan, Tom
2012-01-01
This article uses theory on disability, embodiment and language to explore the production, context and presentation of two pieces of life-writing by Christopher Nolan. It examines Nolan's unusual use of language and form in his presentations of an experience of disability, and considers its literary and political significance. Consideration is…
Li, Bohua; Rindler-Daller, Tanja
2016-01-01
We consider an alternative dark matter candidate, ultralight bosonic dark matter ($m>10^{-22}$eV) described by a complex scalar field (SFDM) with a global U(1) symmetry, for which the associated charge density is conserved after particle production during standard reheating (w=0). We allow for a repulsive self-interaction. In a Lambda-SFDM universe, SFDM starts relativistic, evolving from stiff (w=1) to radiationlike (w=1/3), before becoming nonrelativistic at late times (w=0). Thus, before the radiation-dominated era, there is an earlier era of stiff-SFDM-domination. Transitions between these eras, determined by SFDM particle mass $m$ and the quartic self-interaction coupling strength $\\lambda$, are thus constrained by cosmological observables, particularly N_{eff}, the effective number of neutrino species during BBN, and z_{eq}, the redshift of matter-radiation equality. Furthermore, since the stochastic gravitational wave background (SGWB) from inflation is amplified during the stiff era, it can contribute...
Understanding the Core-Halo Relation of Quantum Wave Dark Matter, $\\psi$DM, from 3D Simulations
Schive, Hsi-Yu; Woo, Tak-Pong; Wong, Shing-Kwong; Chiueh, Tzihong; Broadhurst, Tom; Hwang, W-Y Pauchy
2014-01-01
We examine the nonlinear structure of gravitationally collapsed objects that form in our simulations of wavelike cold dark matter ($\\psi$DM), described by the Schr\\"odinger-Poisson (SP) equation. A distinct gravitationally self-bound solitonic core is found at the center of every halo, with a profile quite different from cores modeled in the warm or self-interacting dark matter scenarios. Furthermore, we show that each solitonic core is surrounded by an extended halo composed of large fluctuating dark matter granules which modulate the halo density on a scale comparable to the diameter of the solitonic core. The scaling symmetry of the SP equation and the uncertainty principle tightly relate the core mass to the halo specific energy, which, in the context of cosmological structure formation, leads to a simple scaling between core mass ($M_c$) and halo mass ($M_h$), $M_c \\propto a^{-1/2} M_h^{1/3}$, where $a$ is the cosmic scale factor. We verify this scaling relation by (i) examining the internal structure of...
Li Biao; Li Yuqi [Nonlinear Science Center, Ningbo University, Ningbo 315211 (China); Zhang Xiaofei; Liu, W M, E-mail: biaolee2000@yahoo.com.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)
2011-09-14
We present two families of one-soliton solutions and three families of two-soliton solutions for a generalized nonlinear Schroedinger equation, which is characterized by the time-dependent scattering length and varying potentials. Then, we investigate the propagation of one-soliton and interactions of two-soliton by some selected control functions. The results show that the intensities of one- and two-soliton first increase rapidly to a peak value, and then decay very slowly to the background value; thus, the lifetimes of both one-soliton and two-soliton in Bose-Einstein condensates can be extended largely at least to the order of the lifetime of a Bose-Einstein condensate in real experiments. Our results open up new ways of considerable experimental interest for the management of matter-wave solitons in Bose-Einstein condensates.
Belobo Belobo, D; Ben-Bolie, G H; Kofane, T C
2015-04-01
By using the F-expansion method associated with four auxiliary equations, i.e., the Bernoulli equation, the Riccati equation, the Lenard equation, and the hyperbolic equation, we present exact explicit solutions describing the dynamics of matter-wave condensates with time-varying two- and three-body nonlinearities. Condensates are trapped in a harmonic potential and they exchange atoms with the thermal cloud. These solutions include the generalized Jacobi elliptic function solutions, hyperbolic function solutions, and trigonometric function solutions. In addition, we have also found rational function solutions. Solutions constructed here have many free parameters that can be used to manipulate and control some important features of the condensate, such as the position, width, velocity, acceleration, and homogeneous phase. The stability of the solutions is confirmed by their long-time numerical behavior.
Development of a Nonlinear Internal Wave Tactical Decision Aid
2016-06-07
of a Nonlinear Internal Wave Tactical Decision Aid 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER...Development of a Nonlinear Internal Wave Tactical Decision Aid Christopher R. Jackson Global Ocean Associates 6220 Jean Louise Way Alexandria...www.internalwaveatlas.com LONG-TERM GOALS The long term goal of the project is to develop a prediction methodology for the occurrence of nonlinear
The main work of astronomer Christoph Scheiner SJ "Rosa Ursina sive Sol" - a summary.
Daxecker, F.
1996-10-01
Christoph Scheiner was born on 25 July 1573 or 1575 in Markt Wald near Mindelheim in the Bavarian part of Swabia. He died on 18 July 1650. In Rome he wrote his main work Rosa Ursina sive Sol and had it printed with the help of a patron, Duke Paulus Jordanus II of Bracciano. The ducal family bore a rose, likened to the Sun in Scheiner's book, on its coat of arms. Rosa Ursina is divided into four volumes. In volume I Scheiner tackles the issue of who was first to discover the sunspots; he also proves that Galilei made errors of observation. Volume II shows illustrations of telescopes, projection methods and the helioscope and compares the optics of a telescope with that of the human eye. In volume III, observations on sunspots are illustrated by 70 copper engravings by David Widemann. Volume IV consists of two parts. The first part again deals with the phenomena of the Sun, such as sunspots and prominences, its period of revolution of 27 days, and the tilt of its axis; the second part is a collection of passages and quotations from the Scriptures, from Church Fathers and philosophers, all designed to prove that Scheiner's interpretation of the geocentric system conformed to Catholic doctrine.
[The professor and his student. The correspondence between Lorenz Heister and Christoph Jacob Trew].
Ruisinger, Marion Maria; Schnalke, Thomas
2004-01-01
Letters were the central medium of communication in the medical scientific community of the 18th century. Professional as well as personal relationships were established among the various correspondents. These relationships constituted the smallest units of communication which contributed to the regional and international scientific network of the Republic of Letters. A correspondence that grew out of a trusted teacher-student relationship could gain an especially intense character both intellectually and personally. This contribution offers an analysis of an example of just such a correspondence. Lorenz Heister (1683--1758), medical professor at the universities of Altdorf and Helmstedt, and his disciple, Christoph Jacob Trew (1695--1769), who became a renowned physician and natural scientist in Nuremberg, communicated in letters to one another over a span of almost forty years. Their correspondence started as a rather asymmetrical dialogue. Over time, however, Heister and Trew came to meet as equals in almost every field of their competence. Their letters reveal a broad spectrum of scientific, organisational, professional, medical and personal issues which formed the basis of a stable and lasting learned correspondence in the age of Enlightenment.
The death of the hero. Christopher Logue's Patrocleia: Orality, Writing, Performance
Andrea Veglia
2012-12-01
Full Text Available Starting from the comparison of three versions (1962, 1997, 2001 of the final part of Patrocleia - the second instalment of the radio adaptation of Homer's Iliad by the English poet Christopher Logue, War Music – I will show the path towards a musical version and an extreme conceptual compression of the Homeric text. War Music, in fact, lives its full potential only in a performative act. Through a stylistic analysis (close reading I will highlight the stages of composition of the episode, and then I will demonstrate that the agony and death of the hero undergo a dramatization that makes Patroclus’ death a theatrical performance under Apollo's direction. Through a close comparison with the Greek text and with the academic translation by Richard Lattimore (1951 I explain in which way Patrocleia aims at the creation of a musical style and epic diction that fit mimetically to the means of oral transmission. This adaptation enters the folds of the Homeric text and amplifies its ambiguities.
Antonio Cascelli
2014-10-01
Full Text Available Quando, nell’undicesimo libro delle Confessioni, S. Agostino si interroga circa la natura del tempo, individua un problema linguistico in senso forte, dove il linguaggio non costituisce una semplice etichetta da attaccare agli eventi ma un modo di entrare in relazione con essi e conoscerli. Quando qualcuno gli domanda cosa sia il tempo, egli non lo sa, cioè non sa come spiegarlo e gli mancano le parole per esprimere qualcosa che, quando nessuno glielo chiede, egli conosce. Come possiamo esprimere il fluire del tempo? Come possiamo dire il tempo e dar voce a una profonda esperienza cognitiva del divenire e della relazione che noi stabiliamo con esso? Queste domande costituiscono le basi del libro di Christopher Hasty. Il suo punto di partenza è la considerazione che, sopprimendo la creatività e la novità dell'effettiva esperienza musicale, l’astrazione dell’analisi tradisce la natura temporale della musica. Al contrario, Hasty vuole prendere in considerazione questa natura temporale e "cercare dei modi di parlare dell’aspetto evanescente della musica, sviluppando concetti che catturino tanto la determinatezza quanto l’indeterminatezza degli eventi al loro passaggio" (p. vii.
Arlt, R; Schmiel, C; Spada, F
2016-01-01
Digital images of the observations printed in the books "Rosa Ursina sive solis" and "Prodromus pro sole mobili" by Christoph Scheiner as well as the drawings from Scheiner's letters to Marcus Welser are analysed in order to obtain information on positions and sizes of sunspots that appeared before the Maunder minimum. In most cases, the given orientation of the ecliptic is used to set up the heliographic coordinate system for the drawings. Positions and sizes are measured manually on the screen. Very early drawings have no indication of their orientation. A rotational matching using common spots of adjacent days is used in some cases, while in other cases, the assumption of images being aligned with a zenith-horizon coordinate system appeared to be the most probable. In total, 8167 sunspots were measured. A distribution of sunspot latitudes versus time (butterfly diagram) is obtained for Scheiner's observations. The observations of 1611 are very inaccurate, the drawings of 1612 have at least an indication of...
Dynamique p-adique (d'apr\\`es des expos\\'es de Jean-Christophe Yoccoz)
Cantat, Serge
2009-01-01
This paper is an introduction to the dynamics of rational fractions over a p-adic field. It follows the lectures that Jean-Christophe Yoccoz gave during the \\'Etats de la recherche in May 2006, and develops certain points. Most of the results to be explained here are due to Benedetto, B\\'ezivin, Hsia, Lubin, Morton, Rivera-Letelier and Silverman. ----- Ce texte est une introduction \\`a la dynamique des fractions rationnelles sur un corps $p$-adique. Il reprend le cours que Jean-Christophe Yoccoz avait fait lors des \\emph{\\'Etats de la recherche} de mai 2006 et en d\\'eveloppe certains points. La plupart des r\\'esultats pr\\'esent\\'es sont d\\^us \\`a Benedetto, B\\'ezivin, Hsia, Lubin, Morton, Rivera-Letelier et Silverman.
Logos y poesía como acontecimientos del mundo y de la carne: Edith Stein y Christophe Lebreton
Cecilia Avenatti de Palumbo
2016-01-01
Full Text Available The scope of the present article is to evidence the confluence of two different kind of speech: the rational and the poetic one, moving from the Works of Edith Stein and Christophe Lebreton. Both types of speech, usually presented as opposed, belong to the realm of the human spirit - incarnated in time. Therefore, they do not exclude each other but they meet themselves at the event of flesh.
Carlos Menéndez-Otero
2011-03-01
Full Text Available Reseñas de los libros de cine Bowery to Broadway. The American Irish in Classic Hollywood Cinema (Christopher Shannon 2010 & New Irish Storytellers. Narrative Strategies in Film (Díóg O’Connell 2010
Szoboszlai, Z; Kertész, Zs; Szikszai, Z; Angyal, A; Furu, E; Török, Zs; Daróczi, L; Kiss, A Z
2012-02-15
In this case study, the elemental composition and mass size distribution of indoor aerosol particles were determined in a working environment where soldering of printed circuit boards (PCB) took place. Single particle analysis using ion and electron microscopy was carried out to obtain more detailed and reliable data about the origin of these particles. As a result, outdoor and indoor aerosol sources such as wave soldering, fluxing processes, workers' activity, mineral dust, biomass burning, fertilizing and other anthropogenic sources could be separated. With the help of scanning electron microscopy, characteristic particle types were identified. On the basis of the mass size distribution data, a stochastic lung deposition model was used to calculate the total and regional deposition efficiencies of the different types of particles within the human respiratory system. The information presented in this study aims to give insights into the detailed characteristics and the health impact of aerosol particles in a working environment where different kinds of soldering activity take place.
Maselli, Andrea; Ferrari, Valeria
2013-01-01
We study how to extract information on the neutron star equation of state from the gravitational wave signal emitted during the coalescence of a binary system composed by two neutron stars or a neutron star and a black hole. We use Post-Newtonian templates which include the tidal deformability parameter and, when tidal disruption occurs before merger, a frequency cut-off. Assuming that this signal is detected by Advanced LIGO/Virgo or ET, we evaluate the uncertainties on these parameters using different data analysis strategies based on the Fisher matrix approach, and on recently obtained analytical fits of the relevant quantities. We find that the tidal deformability is more effective than the stellar compactness to discriminate among different possible equations of state.
Study on the dynamic behavior of matters using laser-driven shock waves in the water confinement
Yu, Hyeonju; Yoh, Jack J.
2015-06-01
The strain rates achievable in laser-driven shock experiments overlap with gas gun and can reach much higher values. The laser-based method also has advantages in terms of system size, cost, repeatability, and controllability. In this research, we aim to measure equation of state, Hugoniot elastic limit, strain rate, and compressive yield strength of target samples by making use of the velocity interferometer or the VISAR. High pressure shock wave is generated by a Q-switched Nd:YAG laser operating at 1.064 μm wavelength with pulse energy up to 3 joules and 9 ns pulse duration. All the experiments are conducted in the water confinement to increase the peak stresses to an order of GPa. Furthermore, quantitative comparisons are made to the existing shock data in order to emphasize the novelty of the proposed setup which is relatively simple and reliable. Corresponding author.
Arlt, R.; Senthamizh Pavai, V.; Schmiel, C.; Spada, F.
2016-11-01
Aims: Digital images of observations printed in the books Rosa Ursina sive solis and Prodromus pro sole mobili by Christoph Scheiner, as well as the drawings from Scheiner's letters to Marcus Welser, are analysed to obtain information on the positions and sizes of sunspots that appeared before the Maunder minimum. Methods: In most cases, the given orientation of the ecliptic is used to set up the heliographic coordinate system for the drawings. Positions and sizes are measured manually on screen. Very early drawings have no indication of their orientation. A rotational matching using common spots of adjacent days is used in some cases, while in other cases, the assumption that images were aligned with a zenith-horizon coordinate system appeared to be the most probable. Results: In total, 8167 sunspots were measured. A distribution of sunspot latitudes versus time (butterfly diagram) is obtained for Scheiner's observations. The observations of 1611 are very inaccurate, the drawings of 1612 have at least an indication of their orientation, while the remaining part of the spot positions from 1618-1631 have good to very good accuracy. We also computed 697 tilt angles of apparently bipolar sunspot groups observed in the period 1618-1631. We find that the average tilt angle of nearly 4 degrees is not significantly different from 20th-century values. Data on the sunspot position and area are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/595/A104
Relic gravity waves and 7 keV dark matter from a GeV scale inflaton
F.L. Bezrukov
2014-09-01
Full Text Available We study the mechanism of generation of 7 keV sterile neutrino Dark Matter (DM in the model with light inflaton χ, which serves as a messenger of scale invariance breaking. In this model the inflaton, in addition to providing reheating to the Standard Model (SM particles, decays directly into sterile neutrinos. The latter are responsible for the active neutrino oscillations via seesaw type I mechanism. While the two sterile neutrinos may also produce the lepton asymmetry in the primordial plasma and hence explain the baryon asymmetry of the Universe, the third one being the lightest may be of 7 keV and serve as DM. For this mechanism to work, the mass of the inflaton is bound to be light (0.1–1 GeV and uniquely determines its properties, which allows to test the model. For particle physics experiments these are: inflaton lifetime (10−5–10−12 s, branching ratio of B-meson to kaon and inflaton (10−6–10−4 and inflaton branching ratios into light SM particles like it would be for the SM Higgs boson of the same mass. For cosmological experiments these are: spectral index of scalar perturbations (ns≃0.957–0.967, and amount of tensor perturbations produced at inflation (tensor-to-scalar ratio r≃0.15–0.005.
Kemp, B. A.
2011-06-01
A century has now passed since the origins of the Abraham-Minkowski controversy pertaining to the correct form of optical momentum in media. Experiment and theory have been applied at both the classical and quantum levels in attempt to resolve the debate. The result of these efforts is the identification of Abraham's kinetic momentum as being responsible for the overall center of mass translations of a medium and Minkowski's canonical or wave momentum as being responsible for translations within or with respect to a medium. In spite of the recent theoretical developments, much confusion still exists regarding the appropriate theory required to predict experimental outcomes and to develop new applications. In this paper, the resolution of the longstanding Abraham-Minkowski controversy is reviewed. The resolution is presented using classical electromagnetic theory and logical interpretation of experiments disseminated over the previous century. Emphasis is placed on applied physics applications: modeling optical manipulation of cells and particles. Although the basic interpretation of optical momentum has been resolved, there is still some uncertainly regarding the complete form of the momentum continuity equation describing electromagnetics. Thus, while a complete picture of electrodynamics has still yet to be fully interpreted, this correspondence should help clarify the state-of-the-art view.
Ducharme, R.; da Paz, I. G.
2016-08-01
In two recent papers exact Hermite-Gaussian solutions to relativistic wave equations were obtained for both electromagnetic and particle beams. The solutions for particle beams correspond to those of the Schrödinger equation in the nonrelativistic limit. Here, it will be shown that each beam particle has additional 4-momentum resulting from transverse localization compared to a free particle traveling in the same direction as the beam with the same speed. This will be referred to as the quantum 4-potential term since it will be shown to play an analogous role in relativistic Hamiltonian quantum mechanics as the Bohm potential in the nonrelativistic quantum Hamilton-Jacobi equation. Low-order localization effects include orbital angular momentum, Gouy phase, and beam spreading. Toward a more systematic approach for calculating localization effects at all orders, it will be shown that both the electromagnetic and quantum 4-potentials couple into the canonical 4-momentum of a particle in a similar way. This offers the prospect that traditional methods used to calculate the affect of an electromagnetic field on a particle can now be adapted to take localization effects into account. The prospects for measuring higher order quantum 4-potential related effects experimentally are also discussed alongside some questions to challenge the quantum information and quantum field theorists.
Li, Bohua; Shapiro, Paul R.; Rindler-Daller, Tanja
2017-06-01
We consider an alternative to WIMP cold dark matter (CDM), ultralight bosonic dark matter (m≥10-22eV) described by a complex scalar field (SFDM) with global U(1) symmetry, for which the comoving particle number density is conserved after particle production during standard reheating. We allow for a repulsive self-interaction. In a ΛSFDM universe, SFDM starts relativistic, evolving from stiff (w=1) to radiationlike (w=1/3), before becoming nonrelativistic at late times (w=0). Thus, before the familiar radiation-dominated era, there is an earlier era of stiff-SFDM-domination, during which the expansion rate is higher than in ΛCDM. SFDM particle mass m and coupling strength λ, of a quartic self-interaction, are therefore constrained by cosmological observables, particularly Neff, the effective number of neutrino species during BBN, and zeq, the redshift of matter-radiation equality. Furthermore, since the stochastic gravitational-wave background (SGWB) from inflation is amplified during the stiff era, it can contribute a radiationlike component large enough to affect these observables by further boosting the expansion rate. Remarkably, this same amplification makes detection of the SGWB possible at high frequencies by current laser interferometer experiments, e.g., aLIGO/Virgo and LISA. For SFDM particle parameters that satisfy these cosmological constraints, the amplified SGWB is detectable by LIGO for a broad range of reheat temperatures Treheat, for values of tensor-to-scalar ratio r currently allowed by CMB polarization measurements. The SGWB is maximally detectable if modes that reentered the horizon when reheating ended have frequencies today in the LIGO sensitive band. For r=0.01, if SFDM parameters are chosen which marginally satisfy the above constraints, the maximally detectable model for (λ/(mc2)2, m)=(10-18eV-1cm3, 8×10-20eV) corresponds to Treheat≈104GeV, for which we predict an aLIGO O1 run detection with SNR~10. Upper limits on the SGWB
Vera M.F. de Lima
2009-03-01
Full Text Available The isolated chick retina provides an in vitro tissue model, in which two protocols were developed to verify the efficacy of a peptide in the excitability control of the central gray matter. In the first, extra-cellular potassium homeostasis is challenged at long intervals and in the second, a wave is trapped in a ring of tissue causing the system to be under self-sustained challenge. Within the neuropil, the extra-cellular potassium transient observed in the first protocol was affected from the initial rising phase to the final concentration at the end of the five-minute pulse. There was no change in the concomitants of excitation waves elicited by the extra-cellular rise of potassium. However, there was an increase on the elicited waves latency and/or a rise in the threshold potassium concentration for these waves to appear. In the second protocol, the wave concomitants and the propagation velocity were affected by the peptide. The results suggest a synergetic action of the peptide on glial and synaptic membranes: by accelerating the glial Na/KATPase and changing the kinetics of the glial potassium channels, with glia tending to accumulate KCl. At the same time, there is an increase in potassium currents through nerve terminals.Retinas de pinto isoladas proporcionam um modelo de tecidos in vitro, para o qual dois protocolos foram desenvolvidos para verificar a eficácia de um peptídeo no controle da excitabilidade da matéria cinzenta central. No primeiro, a homeostase do potássio extra-celular é desafiada por intervalos longos (1 hora e no segundo, uma onda é capturada em um anel de tecido, de tal maneira que o sistema permaneça em estado de desafio auto-sustentado. Dentro da neuropil, o transiente de potássio extra-celular observado no primeiro protocolo foi afetado da fase de início de aumento à concentração final, ao final do pulso de cinco minutos. Não há mudanças nos parâmetros concomitantes das ondas de excitação geradas
Miks ohverdada veel üks põlvkond? / Christopher õBeazley ; interv. Berit Teeäär
õBeazley, Christopher
2008-01-01
Euroopa Parlamendi Balti-Euroopa tugirühma esimees Christopher Beazley vastab küsimustele, mis puudutavad tema huvi Balti riikide ja Läänemere regiooni vastu, Läänemere piirkonnas paiknevate Euroopa Liidu vanade ja uute liikmesriikide kontseptuaalsete erinevuste tõttu tekkida võivaid lahkhelisid, Euroopa Liidu ja Venemaa suhete seisu ja arenguperspektiive, liidu ühise välispoliitika kujunemise võimalikkust, Kaliningradi oblasti demilitariseerimist ning selle enklaavi muutmist Euroopa Liidu ja Venemaa vahelise vabakaubanduse pilootprojektiks, Läänemere ökoloogilise olukorra parandamist
Medicus, Heinrich A.
1974-01-01
Discusses the origin of de Broglie's concept and its influences on his contemporaries, notably on Einstein, Schrodinger, Elsasser, Davisson, and Thomson. Indicates that the theory served not only as the starting point of quantum mechanics, but also opened new experimental possibilities. Historical inaccuracies are corrected with new material…
Can cellulite be treated with low-energy extracorporeal shock wave therapy?
Fiorenzo Angehrn; Christoph Kuhn; Axel Voss
2008-01-01
Fiorenzo Angehrn1, Christoph Kuhn1, Axel Voss21Klinik Piano, Gottstattstrasse 24, Biel, Switzerland; 2SwiTech Medical AG, Kreuzlingen, SwitzerlandAbstract: The present study investigates the effects of low-energy defocused extracorporeal generated shock waves on collagen structure of cellulite afflicted skin. Cellulite measurement using high-resolution ultrasound technology was performed before and after low-energy defocused extracorporeal shock wave therapy (ESWT) in 21 female subjects. ESWT...
Sen, Srimoyee
2016-01-01
We study shock waves in relativistic chiral matter. We argue that the conventional Rankine- Hugoinot relations are modified due to the presence of chiral transport phenomena. We show that the entropy discontinuity in a weak shock wave is linearly proportional to the pressure discontinuity when the effect of chiral transport becomes sufficiently large. We also show that rarefaction shock waves, which do not exist in usual nonchiral fluids, can appear in chiral matter. These features are exemplified by shock propagation in dense neutrino matter in the hydrodynamic regime.
Christophe Kihm, L'Epreuve de l'image : techniques et compétences du corps
2014-01-01
Dans L’Epreuve de l’image, Christophe Kihm, critique et enseignant à la Haute école d’art et de design (HEAD) de Genève, explore les conditions dans lesquelles les corps sont appelés à devenir des images. Comment les images constituent-elles le laboratoire privilégié du geste ? Et de la même manière, comment les mouvements, les mimiques ou les attitudes corporelles sont-elles mises à l’épreuve par l’image ? A travers un choix hétéroclite d’exemples – le mythe d’Œdipe, le « corps-esprit » d’Ho...
Christophe Kihm, L'Epreuve de l'image : techniques et compétences des corps
2014-01-01
Dans L’Epreuve de l’image, Christophe Kihm, critique et enseignant à la Haute école d’art et de design (HEAD) de Genève, explore les conditions dans lesquelles les corps sont appelés à devenir des images. Comment les images constituent-elles le laboratoire privilégié du geste ? Et de la même manière, comment les mouvements, les mimiques ou les attitudes corporelles sont-elles mises à l’épreuve par l’image ? A travers un choix hétéroclite d’exemples – le mythe d’Œdipe, le « corps-esprit » d’Ho...
"O trabalho na forma de alegria juvenil": a ginástica segundo Johann Christoph Friedrich Guts Muths
Evelise Amgarten Quitzau
2012-06-01
Full Text Available Este trabalho tem como objetivo estabelecer uma aproximação com a obra de Johann Christoph Friedrich Guts Muths, pedagogo alemão que, no final do século XVIII, publicou uma das obras fundamentadoras da ginástica alemã: Gymnastik für die Jugend (Ginástica para a Juventude. Seu trabalho baseia-se principalmente nas teorias da denominada polícia médica, e apresenta um forte discurso em defesa da instituição dos exercícios físicos como instrumento de regeneração e fortalecimento da população alemã.
Esther Suzanne Pabst
2009-10-01
Full Text Available Christoph Kucklick reconstructs constructions of masculinity around 1800 on the basis of contemporary writings. Utilizing an approach informed by systems theory, he suggests that gender semantics developing at this time are the result of functional differentiation in modern society. He thus sheds new light on the gender debates of the enlightenment and makes visible those, till now unexamined, developmental and motivational correlations to modern masculinity constructions. Kucklick’s assertion to have been the first to uncover the fact that gender discourse in the enlightenment is contingent on new historical doubt toward masculinity, however, is as untenable as his provocative call for the replacement of the power-theoretical approach with the system-theoretical perspective.
Einasto, Jaan
2013-01-01
I give a review of the development of the concept of dark matter. The dark matter story passed through several stages from a minor observational puzzle to a major challenge for theory of elementary particles. Modern data suggest that dark matter is the dominant matter component in the Universe, and that it consists of some unknown non-baryonic particles. Dark matter is the dominant matter component in the Universe, thus properties of dark matter particles determine the structure of the cosmic...
Christopher Nolan’ın ‘Batman Üçlemesi’ Üzerine İdeolojik Bir İnceleme
BÖLÜKBAŞI, Mustafa
2013-01-01
This article examines the ideological meaning of Batman as a superhero story. To this end, Batman Begins (2005), The Dark Knight (2008), and The Dark Knight Rises (2012), directed by Christopher Nolan, are analyzed in terms of content, revealing their underlying ideology. This study discusses why Batman was created to fight against evil, what is the aim of such a creation, who needs Batman and briefly what Nolan’s Batman trilogy advises us
Christopher Reeve:Superman to the End%克里斯托弗·里夫:永远的超人
顾晓栋
2006-01-01
@@ Though he has played a variety of leading roles, tall, dark, and wholesomely2 handsome Christopher Reeve will always be the definitive3 Superman to an entire generation of "Man of Steel4"fans. That his definitive character was such a model of physical prowess5 only serves to intensify the tragedy of Reeve's post-Superman years, marked by a 1995 horseback riding accident that left him almost completely paralyzed6.
Imari Walker, Sara; Davies, Paul C. W.; Ellis, George F. R.
2017-02-01
1. Introduction Sara Imari Walker, Paul C. W. Davies and F. R. Ellis; Part I. Physics and Life: 2. The 'hard problem' of life Sara Imari Walker and Paul C. W. Davies; 3. Beyond initial conditions and laws of motion: constructor theory of information and life Chiara Marletto; Part II. Bio from Bit: 4. (How) did information emerge? Anne-Marie Grisogono; 5. On the emerging codes for chemical evolution Jillian E. Smith-Carpenter, Sha Li, Jay T. Goodwin, Anil K. Mehta and David G. Lynn; 6. Digital and analogue information in organisms Denis Noble; 7. From entropy to information: biased typewriters and the origin of life Christoph Adami and Thomas Labar; Part III. Life's Hidden Information: 8. Cryptographic nature David Krakauer; 9. Noise and function Steven Weinstein and Theodore Pavlic; 10. The many faces of state space compression David Wolpert, Eric Libby, Joshua Grochow and Simon DeDeo; 11. Causality, information and biological computation: an algorithmic software approach to life, disease and the immune system Hector Zenil, Angelika Schmidt and Jesper Tegnér; Part IV. Complexity and Causality: 12. Life's information hierarchy Jessica Flack; 13. Living through downward causation: from molecules to ecosystems Keith D. Farnsworth, George F. R. Ellis and Luc Jaeger; 14. Automata and animats: from dynamics to cause-effect structures Larissa Albantakis and Giulio Tononi; 15. Biological information, causality and specificity - an intimate relationship Karola Stotz and Paul Griffiths; Part V. From Matter to Mind: 16. Major transitions in political order Simon DeDeo; 17. Bits from biology for computational intelligence Michael Wibral, Joseph Lizier and Viola Priesemann; 18. Machine learning and the questions it raises G. Andrew D. Briggs and Dawid Potgieter.
The Eighth Liquid Matter Conference.
Dellago, Christoph; Kahl, Gerhard; Likos, Christos N
2012-07-18
The Eighth Liquid Matter Conference (LMC8) was held at the Universität Wien from 6-10 September 2011. Initiated in 1990, the conferences of this series cover a broad range of highly interdisciplinary topics, ranging from simple liquids to soft matter and biophysical systems. The vast spectrum of scientific subjects presented and discussed at the LMC8 is reflected in the themes of the ten symposia: Ionic and quantum liquids, liquid metals Water, solutions and reaction dynamics Liquid crystals Polymers, polyelectrolytes, biopolymers Colloids Films, foams, surfactants, emulsions, aerosols Confined fluids, interfacial phenomena Supercooled liquids, glasses, gels Non-equilibrium systems, rheology, nanofluids Biofluids, active matter This special issue contains scientific papers, authored by participants of the LMC8, which provide a cross-section of the scientific activities in current liquid matter science, as discussed at the conference, and demonstrate the scientific as well as methodological progress made in this field over the past couple of years. The Eighth Liquid Matter Conference contents The Eighth Liquid Matter ConferenceChristoph Dellago, Gerhard Kahl and Christos N Likos Comparing light-induced colloidal quasicrystals with different rotational symmetriesMichael Schmiedeberg and Holger Stark Hydrogen bond network relaxation in aqueous polyelectrolyte solutions: the effect of temperatureS Sarti, D Truzzolillo and F Bordi Equilibrium concentration profiles and sedimentation kinetics of colloidal gels under gravitational stressS Buzzaccaro, E Secchi, G Brambilla, R Piazza and L Cipelletti The capillary interaction between two vertical cylindersHimantha Cooray, Pietro Cicuta and Dominic Vella Hydrodynamic and viscoelastic effects in polymer diffusionJ Farago, H Meyer, J Baschnagel and A N Semenov A density-functional theory study of microphase formation in binary Gaussian mixturesM Carta, D Pini, A Parola and L Reatto Microcanonical determination of the
Henderikx Freitas, Fernanda; Siegel, David A.; Maritorena, Stéphane; Fields, Erik
2017-01-01
Satellite observations of chlorophyll in coastal waters are often described in terms of changes in productivity in response to regional upwelling processes while optical backscattering coefficients are more often linked to episodic inputs of suspended sediments from storm runoff. Here we show that the surface gravity wave resuspension of sediments has a larger role in controlling backscatter than previously considered. Almost 18 years of SeaWiFS, MODIS, MERIS, and VIIRS satellite imagery of the Santa Barbara Channel, California and its surrounding waters spectrally merged with the Garver-Siegel-Maritorena bio-optical model were used to assess the controls on suspended particle distributions. Analysis revealed that chlorophyll blooms in the warmer portions of the domain occur in phase with SST minima, usually in early spring, while blooms in the cooler regions lag SST minima and occur simultaneously to the strongest equatorward winds every year, often in the summer. Tight coupling between the optical variables was seen in offshore areas, as expected for productive waters. However, values of backscatter near the coast were primarily modulated by surface waves. This relationship holds throughout all seasons and is stronger within the 100 m isobath, but often extends tens of kilometers offshore. This forcing of particle resuspension by surface waves is likely a feature ubiquitous in all coastal oceans characterized by fine sediments. The implication of surface wave processes determining suspended particle loads far beyond the surf zone has large consequences for the interpretation of satellite ocean color signals in coastal waters and potentially redefines the extent of the littoral zone.
Einasto, J.
2011-01-01
I give a review of the development of the concept of dark matter. The dark matter story passed through several stages from a minor observational puzzle to a major challenge for theory of elementary particles. Modern data suggest that dark matter is the dominant matter component in the Universe, and that it consists of some unknown non-baryonic particles. Properties of dark matter particles determine the structure of the cosmic web.
Angelo, Joseph A
2011-01-01
Supported by a generous quantity of full-color illustrations and interesting sidebars, Solid Matter introduces the basic characteristics and properties of solid matter. It briefly describes the cosmic connection of the elements, leading readers through several key events in human pre-history that resulted in more advanced uses of matter in the solid state. Chapters include:. -Solid Matter: An Initial Perspective. -Physical Behavior of Matter. -The Gravity of Matter. -Fundamentals of Materials Science. -Rocks and Minerals. -Metals. -Building Materials. -Carbon Earth's Most Versatile Element. -S
Unistuste vabrik / Christopher Helman
Helman, Christopher
2014-01-01
Ameerika Ühendriikides Georgias asuv Southwire tehas võttis 2007. aastal kasutusele programmi, mis võimaldab probleemsetel teismelistel osa päevast töötada ja osa õppida, et omandada gümnaasiumiharidus
Tiec, Alexandre Le
2016-01-01
The existence of gravitational radiation is a natural prediction of any relativistic description of the gravitational interaction. In this chapter, we focus on gravitational waves, as predicted by Einstein's general theory of relativity. First, we introduce those mathematical concepts that are necessary to properly formulate the physical theory, such as the notions of manifold, vector, tensor, metric, connection and curvature. Second, we motivate, formulate and then discuss Einstein's equation, which relates the geometry of spacetime to its matter content. Gravitational waves are later introduced as solutions of the linearized Einstein equation around flat spacetime. These waves are shown to propagate at the speed of light and to possess two polarization states. Gravitational waves can interact with matter, allowing for their direct detection by means of laser interferometers. Finally, Einstein's quadrupole formulas are derived and used to show that nonspherical compact objects moving at relativistic speeds a...
Hasse Jørgensen, Stina
2011-01-01
About Speech Matters - Katarina Gregos, the Greek curator's exhibition at the Danish Pavillion, the Venice Biannual 2011.......About Speech Matters - Katarina Gregos, the Greek curator's exhibition at the Danish Pavillion, the Venice Biannual 2011....
... Emergency Room? What Happens in the Operating Room? Memory Matters KidsHealth > For Kids > Memory Matters A A ... of your complex and multitalented brain. What Is Memory? When an event happens, when you learn something, ...
Fabrice Schurmans
2013-11-01
Full Text Available This paper analyzes the concepts of history, memory and forgetfulness in the plays La tragédie du roi Christophe (1970 by Césaire and A Revolta da Casa dos Ídolos (1980 by Pepetela in order to disclose how these works of fiction question and challenge hegemonic history. The study of the staging of memory and history in those plays is based on an articulation of the hermeneutics of literary texts with Stéphane Mosès’s elaboration on the critiques of Benjamin, Rosenzweig and Scholem.
Chiao, R Y; Chiao, Raymond Y.; Fitelson, Walter J.
2006-01-01
Measurements of the tunneling time are briefly reviewed. Next, time and matter in general relativity and quantum mechanics is examined. In particular, the question arises: How does gravitational radiation interact with a coherent quantum many-body system (a ``quantum fluid'')? A minimal coupling rule for the coupling of the electron spin to curved spacetime in general relativity implies the possibility of a coupling between electromagnetic (EM) and gravitational (GR) radiation mediated by a quantum Hall fluid. This suggests that quantum transducers between these two kinds of radiation fields might exist. We report here on a first attempt at a Hertz-type experiment, in which a high-$\\rm{T_c}$ superconductor (YBCO) was the material used as a quantum transducer to convert EM into GR microwaves, and a second piece of YBCO in a separate apparatus was used to back-convert GR into EM microwaves. An upper limit on the conversion efficiency of YBCO was measured to be $1.6\\times10^{-5}$.
Trout, Andrew T; Dillman, Jonathan R; Xanthakos, Stavra; Kohli, Rohit; Sprague, Garrett; Serai, Suraj; Mahley, Alana D; Podberesky, Daniel J
2016-11-01
Purpose To evaluate the correlation between ultrasonographic (US) point shear-wave elastography (SWE) and magnetic resonance (MR) elastography liver shear-wave speed (SWS) measurements in a pediatric population and to determine if US data dispersion affects this relationship. Materials and Methods Institutional review board approval was obtained for this HIPAA-compliant investigation; informed consent and patient assent (as indicated) were obtained. Patients (age range, 0-21 years) undergoing clinical liver MR elastography between July 2014 and November 2015 were prospectively enrolled. Patients underwent two-dimensional gradient-recalled-echo 1.5-T MR elastography with point SWE performed immediately before or immediately after MR elastography. Spearman rank correlation coefficients were calculated to assess the relationship and agreement between point SWE and MR elastography SWS measurements. Uni- and multivariate logistic regression were performed to identify predictors of US data dispersion, with the best multivariate model selected based on Akaike information criterion. Results A total of 55 patients (24 female) were enrolled (mean age, 14.0 years ± 3.9 (standard deviation) (range, 3.5-21.4 years). There was fair correlation between point SWE and MR elastography SWS values for all patients (ρ = 0.33, P = .016). Correlation was substantial, however, when including only patients with minimal US data dispersion (n = 26, ρ = 0.61, P = .001). Mean body mass index (BMI) was significantly lower in patients with minimal US data dispersion than in those with substantial US data dispersion (25.4 kg/m(2) ± 7.8 vs 32.3 kg/m(2) ± 8.3, P = .003). At univariate analysis, BMI (odds ratio, 1.12; 95% confidence interval [CI]: 1.03, 1.21; P = .006) and abdominal wall thickness (odds ratio, 2.50; 95% CI: 1.32, 4.74; P = .005) were significant predictors of US data dispersion. In the best multivariate model, BMI was the only significant predictor (odds ratio, 1.11; 95% CI: 1
Varkey, M.J.
or change. If ini- tially, only a thin layer of air close to the water surface matters in the mo- mentum transfer from wind to water, afterwards with strong winds, a layer of air upto say 15 to 30 metres comes Small sand waves formed on a seashore due... it breaks with a heading wind or on a beach). Consider an open sea of say 1000 square kilometres wherein billions of 'pushes' and 'pulls' happen over tens of hours, causing uncountable number of waves and wave groups of various types moving in different...
Anna-Catharina Gebbers
2012-05-01
Full Text Available The following consideration of Christoph Schlingensief’s production of The Flying Dutchman in Manaus, Brazil, in 2007 is based both on the screening of a documentary film of the performance together with film- and text-based supplementary materials as well as on interviews with members of Christoph Schlingensief’s team who were directly involved. On the one hand, there is the fundamental problem of performance analysis, while on the other hand, there are Schlingen-sief’s multifaceted procedures to be taken into account. In my view this approach comes closer to Christoph Schlingensief’s working method than does an attempt at a congruent retelling, which blurs all differences for the sake of a combined consideration. Schlingensief’s stagings were also created with a fragmentation of perspective, made possible often by a very precise script, the various production ele-ments, and site-specific features used on a par with the action.
Støverud, Karen H; Alnæs, Martin; Langtangen, Hans Petter; Haughton, Victor; Mardal, Kent-André
2016-01-01
Syringomyelia, fluid-filled cavities within the spinal cord, occurs frequently in association with a Chiari I malformation and produces some of its most severe neurological symptoms. The exact mechanism causing syringomyelia remains unknown. Since syringomyelia occurs frequently in association with obstructed cerebrospinal fluid (CSF) flow, it has been hypothesized that syrinx formation is mechanically driven. In this study we model the spinal cord tissue either as a poro-elastic medium or as a solid linear elastic medium, and simulate the propagation of pressure waves through an anatomically plausible 3D geometry, with boundary conditions based on in vivo CSF pressure measurements. Then various anatomic and tissue properties are modified, resulting in a total of 11 variations of the model that are compared. The results show that an open segment of the central canal and a stiff pia (relative to the cord) both increase the radial pressure gradients and enhance interstitial fluid flow in the central canal. The anterior median fissure, anisotropic permeability of the white matter, and Poisson ratio play minor roles.
Dolgov, A. D.
These lectures have been given to particle physicists, mostly experimentalists and very briefly and at a pedestrian level review the problems of dark matter. The content of the lectures is the following: 1. Introduction. 2. Cosmological background. 3. Luminous matter. 4. Primordial nucleosynthesis and the total amount of baryons. 5. Gravitating invisible matter. 6. Baryonic crisis. 7. Inflationary omega. 8. Intermediate summary. 9. Possible forms of dark matter. 10. Structure formation: basic assumptions. 11. Structure formations: basics of the theory. 12. Evolution of perturbations with different forms of dark matter. 13. Conclusion. The presentation and conclusion reflect personal view of the author that a considerable amount of invisible energy in the universe is in the form of vacuum energy (cosmological constant) and possibly in the form of a classical field which adjusts vacuum energy to the value permitted and requested by astronomical data.
Cooper, Andrew
2017-03-01
Unlike many recent studies on the notion of lifestyle, Christopher Mayes' The Biopolitics of Lifestyle balances theoretical rigour with empirical investigation to problematize the use of lifestyle in public health strategies. Not only does Mayes' book expose the unjustified emphasis on individual autonomy undergirding neoliberal strategies of governance and contemporary ethical theory, it also marks a significant step forward in enhancing our understanding of one of Foucault's most underappreciated concepts, the dispositif. In clearly framing the import of Foucaultian analysis and placing it against the backdrop of the obesity epidemic, Mayes continues his contributions towards a productive space wherein practitioners, social theorists, and ethicists can genuinely and self-reflectively exchange knowledges in order to respond to living issues of ethical import.
A Máquina Teórica: O Discurso de Christopher Norris sobre o Pós-Modernismo na Década de Noventa
Adam Sharman
1997-01-01
opresente ensaio oferece uma exegese crítica dos sete livros que, até o final de 1997, o teórico e crítico britânico Christopher Norman dedicou ao pós-modernismo, considerando-se que a temática de Norris é a teoria pósmodernista, não os artefatos culturais ou processos pósmodernistas pelos quais ele demonstra pouco interesse. Nessa trajetória, são entrelaçados os fios de diversas questões: o entendimento de Norris do pós-modernismo; as objeções que ele faz à teoria pós-modernista; o teor de s...
Gravitational-wave mediated preheating
Stephon Alexander
2015-04-01
Full Text Available We propose a new preheating mechanism through the coupling of the gravitational field to both the inflaton and matter fields, without direct inflaton–matter couplings. The inflaton transfers power to the matter fields through interactions with gravitational waves, which are exponentially enhanced due to an inflation–graviton coupling. One such coupling is the product of the inflaton to the Pontryagin density, as in dynamical Chern–Simons gravity. The energy scales involved are constrained by requiring that preheating happens fast during matter domination.
International Planned Parenthood Federation, London (England).
Data relating to population and family planning in 17 foreign countries are presented in these situation reports. Countries included are Afghanistan, Bahrein, Brazil, Ecuador, Indonesia, Iraq, Morocco, Paraguay, People's Democratic Republic of Yemen, Peru, Qatar, Saudi Arabia, Sri Lanka, St. Christopher/Nevis, Sudan, United Arab Emirates, and…
Resonance Van Hove Singularities in Wave Kinetics
Shi, Yi-Kang
2015-01-01
Wave kinetic theory has been developed to describe the statistical dynamics of weakly nonlinear, dispersive waves. However, we show that systems which are generally dispersive can have resonant sets of wave modes with identical group velocities, leading to a local breakdown of dispersivity. This shows up as a geometric singularity of the resonant manifold and possibly as an infinite phase measure in the collision integral. Such singularities occur widely for classical wave systems, including acoustical waves, Rossby waves, helical waves in rotating fluids, light waves in nonlinear optics and also in quantum transport, e.g. kinetics of electron-hole excitations (matter waves) in graphene. These singularities are the exact analogue of the critical points found by Van Hove in 1953 for phonon dispersion relations in crystals. The importance of these singularities in wave kinetics depends on the dimension of phase space $D=(N-2)d$ ($d$ physical space dimension, $N$ the number of waves in resonance) and the degree ...
30th International Symposium on Shock Waves
Sadot, Oren; Igra, Ozer
2017-01-01
These proceedings collect the papers presented at the 30th International Symposium on Shock Waves (ISSW30), which was held in Tel-Aviv Israel from July 19 to July 24, 2015. The Symposium was organized by Ortra Ltd. The ISSW30 focused on the state of knowledge of the following areas: Nozzle Flow, Supersonic and Hypersonic Flows with Shocks, Supersonic Jets, Chemical Kinetics, Chemical Reacting Flows, Detonation, Combustion, Ignition, Shock Wave Reflection and Interaction, Shock Wave Interaction with Obstacles, Shock Wave Interaction with Porous Media, Shock Wave Interaction with Granular Media, Shock Wave Interaction with Dusty Media, Plasma, Magnetohyrdrodynamics, Re-entry to Earth Atmosphere, Shock Waves in Rarefied Gases, Shock Waves in Condensed Matter (Solids and Liquids), Shock Waves in Dense Gases, Shock Wave Focusing, Richtmyer-Meshkov Instability, Shock Boundary Layer Interaction, Multiphase Flow, Blast Waves, Facilities, Flow Visualization, and Numerical Methods. The two volumes serve as a reference ...
Angelo, Joseph A
2011-01-01
aseous Matter focuses on the many important discoveries that led to the scientific interpretation of matter in the gaseous state. This new, full-color resource describes the basic characteristics and properties of several important gases, including air, hydrogen, helium, oxygen, and nitrogen. The nature and scope of the science of fluids is discussed in great detail, highlighting the most important scientific principles upon which the field is based. Chapters include:. Gaseous Matter An Initial Perspective. Physical Characteristics of Gases. The Rise of the Science of Gases. Kinetic Theory of
Acoustics waves and oscillations
Sen, S.N.
2013-01-01
Parameters of acoustics presented in a logical and lucid style Physical principles discussed with mathematical formulations Importance of ultrasonic waves highlighted Dispersion of ultrasonic waves in viscous liquids explained This book presents the theory of waves and oscillations and various applications of acoustics in a logical and simple form. The physical principles have been explained with necessary mathematical formulation and supported by experimental layout wherever possible. Incorporating the classical view point all aspects of acoustic waves and oscillations have been discussed together with detailed elaboration of modern technological applications of sound. A separate chapter on ultrasonics emphasizes the importance of this branch of science in fundamental and applied research. In this edition a new chapter ''Hypersonic Velocity in Viscous Liquids as revealed from Brillouin Spectra'' has been added. The book is expected to present to its readers a comprehensive presentation of the subject matter...
CERN
2016-01-01
This video is a teaser-introduction to the Antimatter Matters exhibtion at the Royal Society's Summer Science exhibition July 4-10 2016. The exhibition is jointly organised and hosted by UK members of the ALPHA and LHCb collaborations.
Rivasseau, Vincent; Fuchs, Jean-Nöel
2017-01-01
This fifteenth volume of the Poincare Seminar Series, Dirac Matter, describes the surprising resurgence, as a low-energy effective theory of conducting electrons in many condensed matter systems, including graphene and topological insulators, of the famous equation originally invented by P.A.M. Dirac for relativistic quantum mechanics. In five highly pedagogical articles, as befits their origin in lectures to a broad scientific audience, this book explains why Dirac matters. Highlights include the detailed "Graphene and Relativistic Quantum Physics", written by the experimental pioneer, Philip Kim, and devoted to graphene, a form of carbon crystallized in a two-dimensional hexagonal lattice, from its discovery in 2004-2005 by the future Nobel prize winners Kostya Novoselov and Andre Geim to the so-called relativistic quantum Hall effect; the review entitled "Dirac Fermions in Condensed Matter and Beyond", written by two prominent theoreticians, Mark Goerbig and Gilles Montambaux, who consider many other mater...
Waves and causality in higher dimensions
Wesson, Paul S
2015-01-01
We give a new, wave-like solution of the field equations of five-dimensional relativity. In ordinary three-dimensional space, the waves resemble de Broglie or matter waves, whose puzzling behaviour can be better understood in terms of one or more extra dimensions. Causality is appropriately defined by a null higher-dimensional interval. It may be possible to test the properties of these waves in the laboratory.
Waves and causality in higher dimensions
Wesson, Paul S., E-mail: psw.papers@yahoo.ca [Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, N2L 3G1 (Canada); Overduin, James M., E-mail: joverduin@towson.edu [Department of Physics, Astronomy and Geosciences, Towson University, Towson, MD, 21252 (United States); Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD, 21218 (United States)
2015-11-12
We give a new, wave-like solution of the field equations of five-dimensional relativity. In ordinary three-dimensional space, the waves resemble de Broglie or matter waves, whose puzzling behaviour can be better understood in terms of one or more extra dimensions. Causality is appropriately defined by a null higher-dimensional interval. It may be possible to test the properties of these waves in the laboratory.
This book is dedicated to various aspects of electromagnetic wave theory and its applications in science and technology. The covered topics include the fundamental physics of electromagnetic waves, theory of electromagnetic wave propagation and scattering, methods of computational analysis...
Inertial quantum sensors using light and matter
Barrett, B; Bouyer, P
2016-01-01
The past few decades have seen dramatic progress in our ability to manipulate and coherently control matter-waves. Although the duality between particles and waves has been well tested since de Broglie introduced the matter-wave analog of the optical wavelength in 1924, manipulating atoms with a level of coherence that enables one to use these properties for precision measurements has only become possible with our ability to produce atomic samples exhibiting temperatures of only a few millionths of a degree above absolute zero. Since the initial experiments a few decades ago, the field of atom optics has developed in many ways, with both fundamental and applied significance. The exquisite control of matter waves offers the prospect of a new generation of force sensors exhibiting unprecedented sensitivity and accuracy, for applications from navigation and geophysics to tests of general relativity. Thanks to the latest developments in this field, the first commercial products using this quantum technology are n...
Hybridizing matter-wave and classical accelerometers
Lautier, J.; Volodimer, L.; Hardin, T.; Merlet, S.; Lours, M.; Pereira Dos Santos, F.; Landragin, A.
2014-10-01
We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performance without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely, the dead times between consecutive measurements.
Hybridizing matter-wave and classical accelerometers
Lautier, J.; Volodimer, L.; Hardin, T.; Merlet, S.; Lours, M.; Pereira Dos Santos, F.; Landragin, A., E-mail: arnaud.landragin@obspm.fr [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 avenue de l' Observatoire, 75014 Paris (France)
2014-10-06
We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performance without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely, the dead times between consecutive measurements.
Hybridizing matter-wave and classical accelerometers
Lautier, Jean; Hardin, Thomas; Merlet, Sebastien; Santos, Franck Pereira Dos; Landragin, Arnaud
2014-01-01
We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performances without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely the dead times between consecutive measurements.
Neutrino flavor oscillations in rotating matter
Dvornikov, Maxim
2010-01-01
We study the evolution of the neutrinos system in rotating matter. Neutrinos are supposed to be mixed massive particles interacting with background fermions by means of the electroweak forces. First we find the solutions of wave equations for the neutrino mass eigenstates in matter. Then we study the behavior of neutrino flavor eigenstates in background matter. The problems of neutrino bound states and neutrino flavor oscillations are discussed. We also derive the analog of the quantum mechanical evolution equation for the system of two flavor neutrinos in rotating matter and analyze its solution for the particular initial condition for neutrino flavor eigenstates.
Bird, Simeon; Cholis, Ilias; Muñoz, Julian B; Ali-Haïmoud, Yacine; Kamionkowski, Marc; Kovetz, Ely D; Raccanelli, Alvise; Riess, Adam G
2016-05-20
We consider the possibility that the black-hole (BH) binary detected by LIGO may be a signature of dark matter. Interestingly enough, there remains a window for masses 20M_{⊙}≲M_{bh}≲100M_{⊙} where primordial black holes (PBHs) may constitute the dark matter. If two BHs in a galactic halo pass sufficiently close, they radiate enough energy in gravitational waves to become gravitationally bound. The bound BHs will rapidly spiral inward due to the emission of gravitational radiation and ultimately will merge. Uncertainties in the rate for such events arise from our imprecise knowledge of the phase-space structure of galactic halos on the smallest scales. Still, reasonable estimates span a range that overlaps the 2-53 Gpc^{-3} yr^{-1} rate estimated from GW150914, thus raising the possibility that LIGO has detected PBH dark matter. PBH mergers are likely to be distributed spatially more like dark matter than luminous matter and have neither optical nor neutrino counterparts. They may be distinguished from mergers of BHs from more traditional astrophysical sources through the observed mass spectrum, their high ellipticities, or their stochastic gravitational wave background. Next-generation experiments will be invaluable in performing these tests.
The equilibrium classical scatter spectrum of waves
Guruprasad, V
2016-01-01
Regardless of the unspecific notions of photons as light complexes, radiation bundles or wave packets, the radiation from a single state transition is at most a single continuous wave train that starts and ends with the transition. The radiation equilibrium spectrum must be the superposition sum of the spectra of such wave trains. A classical equipartition of wave trains cannot diverge since they would be finite in number, whereas standing wave modes are by definition infinite, which had doomed Rayleigh's theory, and concern only the total radiation. Wave trains are the microscopic entities of radiation interacting with matter, that correspond to molecules in kinetic theory. Their quantization came from matter transitions in Einstein's 1917 derivation of Planck's law. The spectral scatter of wave trains by Doppler shifts, which cause the wavelength displacements in Wien's law used for the frequency dependence in Einstein's derivation, is shown to yield the shape of the Planck spectrum. A Lorentz transform pro...
Outlook for Detecting Gravitational Waves with Pulsars
Kohler, Susanna
2016-04-01
Though the recent discovery of GW150914 is a thrilling success in the field of gravitational-wave astronomy, LIGO is only one tool the scientific community is using to hunt for these elusive signals. After 10 years of unsuccessful searching, how likely is it that pulsar-timing-array projects will make their own first detection soon?Frequency ranges for gravitational waves produced by different astrophysical sources. Pulsar timing arrays such as the EPTA and IPTA are used to detect low-frequency gravitational waves generated by the stochastic background and supermassive black hole binaries. [Christopher Moore, Robert Cole and Christopher Berry]Supermassive BackgroundGround-based laser interferometers like LIGO are ideal for probing ripples in space-time caused by the merger of stellar-mass black holes; these mergers cause chirps in the frequency range of tens to thousands of hertz. But how do we pick up the extremely low-frequency, nanohertz background signal caused by the orbits of pairs of supermassive black holes? For that, we need pulsar timing arrays.Pulsar timing arrays are sets of pulsars whose signals are analyzed to look for correlations in the pulse arrival time. As the space-time between us and a pulsar is stretched and then compressed by a passing gravitational wave, the pulsars pulses should arrive a little late and then a little early. Comparing these timing residuals in an array of pulsars could theoretically allow for the detection of the gravitational waves causing them.Globally, there are currently four pulsar timing array projects actively searching for this signal, with a fifth planned for the future. Now a team of scientists led by Stephen Taylor (NASA-JPL/Caltech) has estimated the likelihood that these projects will successfully detect gravitational waves in the future.Probability for SuccessExpected detection probability of the gravitational-wave background as a function of observing time, for five different pulsar timing arrays. Optimistic
Astronomical Constraints on Quantum Cold Dark Matter
Spivey, Shane; Musielak, Z.; Fry, J.
2012-01-01
A model of quantum (`fuzzy') cold dark matter that accounts for both the halo core problem and the missing dwarf galaxies problem, which plague the usual cold dark matter paradigm, is developed. The model requires that a cold dark matter particle has a mass so small that its only allowed physical description is a quantum wave function. Each such particle in a galactic halo is bound to a gravitational potential that is created by luminous matter and by the halo itself, and the resulting wave function is described by a Schrödinger equation. To solve this equation on a galactic scale, we impose astronomical constraints that involve several density profiles used to fit data from simulations of dark matter galactic halos. The solutions to the Schrödinger equation are quantum waves which resemble the density profiles acquired from simulations, and they are used to determine the mass of the cold dark matter particle. The effects of adding certain types of baryonic matter to the halo, such as a dwarf elliptical galaxy or a supermassive black hole, are also discussed.
Meiswinkel, R; Labuschagne, K; Goffredo, M
2004-01-01
The biting midge, Culicoides paolae Boorman, described from specimens collected in the extreme south of Italy in 1996, belongs in the subgenus Drymodesmyia. This subgenus was erected by Vargas in 1960 for the so-called Copiosus species group, an assemblage of 22 species endemic to the tropical regions of the New World and, where known, breed in vegetative materials including the decaying leaves (cladodes) and fruits of Central American cacti. The Mexican peoples have utilised these cacti for over 9,000 years; one of these, Opuntia ficus-indica Linnaeus, was brought to Europe by Christopher Columbus following his voyages of discovery. As a taxon C. paolae is very similar to the Central American C. jamaicensis Edwards, 1922 raising the possibility that it (or a closely related species of Drymodesmyia) was introduced into the Mediterranean Region at the time of Columbus, but was (perplexingly) discovered only 500 years later and named C. paolae. The comparison of Sardinian specimens of C. paolae with Panamanian material of C. jamaicensis (housed in the Natural History Museum in London) confirmed the two species to be very similar but unusual differences were noted around the precise distribution of the sensilla coeloconica on the female flagellum. Until it is understood whether these differences represent either intra- or interspecific variation, the question of the possible synonymy of C. paolae must be held in abeyance.
PREFACE: The Eighth Liquid Matter Conference The Eighth Liquid Matter Conference
Dellago, Christoph; Kahl, Gerhard; Likos, Christos N.
2012-07-01
The Eighth Liquid Matter Conference (LMC8) was held at the Universität Wien from 6-10 September 2011. Initiated in 1990, the conferences of this series cover a broad range of highly interdisciplinary topics, ranging from simple liquids to soft matter and biophysical systems. The vast spectrum of scientific subjects presented and discussed at the LMC8 is reflected in the themes of the ten symposia: Ionic and quantum liquids, liquid metals Water, solutions and reaction dynamics Liquid crystals Polymers, polyelectrolytes, biopolymers Colloids Films, foams, surfactants, emulsions, aerosols Confined fluids, interfacial phenomena Supercooled liquids, glasses, gels Non-equilibrium systems, rheology, nanofluids Biofluids, active matter This special issue contains scientific papers, authored by participants of the LMC8, which provide a cross-section of the scientific activities in current liquid matter science, as discussed at the conference, and demonstrate the scientific as well as methodological progress made in this field over the past couple of years. The Eighth Liquid Matter Conference contents The Eighth Liquid Matter ConferenceChristoph Dellago, Gerhard Kahl and Christos N Likos Comparing light-induced colloidal quasicrystals with different rotational symmetriesMichael Schmiedeberg and Holger Stark Hydrogen bond network relaxation in aqueous polyelectrolyte solutions: the effect of temperatureS Sarti, D Truzzolillo and F Bordi Equilibrium concentration profiles and sedimentation kinetics of colloidal gels under gravitational stressS Buzzaccaro, E Secchi, G Brambilla, R Piazza and L Cipelletti The capillary interaction between two vertical cylindersHimantha Cooray, Pietro Cicuta and Dominic Vella Hydrodynamic and viscoelastic effects in polymer diffusionJ Farago, H Meyer, J Baschnagel and A N Semenov A density-functional theory study of microphase formation in binary Gaussian mixturesM Carta, D Pini, A Parola and L Reatto Microcanonical determination of the
Advances in condensed matter optics
Chen, Liangyao; Jiang, Xunya; Jin, Kuijuan; Liu, Hui; Zhao, Haibin
2015-01-01
This book describes some of the more recent progresses and developmentsin the study of condensed matter optics in both theoretic and experimental fields.It will help readers, especially graduate students and scientists who are studying and working in the nano-photonic field, to understand more deeply the characteristics of light waves propagated in nano-structure-based materials with potential applications in the future.
Swanson, DG
1989-01-01
Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th
Andreasen, Karen Egedal; Rasmussen, Annette
During 2011 national standardised testing within areas such as reading, mathematics, science etc. has been introduced in Danish compulsory school by the Educational Ministry as something new. The inspirations behind this initiative are both the international comparative educational studies such a...... the introduction of standardised testing meens to pupils perception of school matters, selfperception etc. In my analysis and discussion I will among others draw on Basil Bernsteins theoretical...
Heat Waves Dangers we face during periods of very high temperatures include: Heat cramps: These are muscular pains and ... having trouble with the heat. If a heat wave is predicted or happening… - Slow down. Avoid strenuous ...
Kramer, Morten; Brorsen, Michael; Frigaard, Peter
Denne rapport beskriver numeriske beregninger af forskellige flydergeometrier for bølgeenergianlæget Wave Star.......Denne rapport beskriver numeriske beregninger af forskellige flydergeometrier for bølgeenergianlæget Wave Star....
Wave diffraction by a cosmic string
Fernández-Núñez, Isabel
2016-01-01
We show that if a cosmic string exists, it may be identified through characteristic diffraction pattern in the energy spectrum of the observed signal. In particular, if the string is on the line of sight, the wave field is shown to fit the Cornu spiral. We suggest a simple procedure, based on Keller's geometrical theory of diffraction, which allows to explain wave effects in conical spacetime of a cosmic string in terms of interference of four characteristic rays. Our results are supposed to be valid for scalar massless waves, including gravitational waves, electromagnetic waves, or even sound in case of condensed matter systems with analogous topological defects.
Wave diffraction by a cosmic string
Fernández-Núñez, Isabel; Bulashenko, Oleg
2016-08-01
We show that if a cosmic string exists, it may be identified through characteristic diffraction pattern in the energy spectrum of the observed signal. In particular, if the string is on the line of sight, the wave field is shown to fit the Cornu spiral. We suggest a simple procedure, based on Keller's geometrical theory of diffraction, which allows to explain wave effects in conical spacetime of a cosmic string in terms of interference of four characteristic rays. Our results are supposed to be valid for scalar massless waves, including gravitational waves, electromagnetic waves, or even sound in case of condensed matter systems with analogous topological defects.
Nonlinear waves in strongly interacting relativistic fluids
Fogaça, D A; Filho, L G Ferreira
2013-01-01
During the past decades the study of strongly interacting fluids experienced a tremendous progress. In the relativistic heavy ion accelerators, specially the RHIC and LHC colliders, it became possible to study not only fluids made of hadronic matter but also fluids of quarks and gluons. Part of the physics program of these machines is the observation of waves in this strongly interacting medium. From the theoretical point of view, these waves are often treated with li-nearized hydrodynamics. In this text we review the attempts to go beyond linearization. We show how to use the Reductive Perturbation Method to expand the equations of (ideal and viscous) relativistic hydrodynamics to obtain nonlinear wave equations. These nonlinear wave equations govern the evolution of energy density perturbations (in hot quark gluon plasma) or baryon density perturbations (in cold quark gluon plasma and nuclear matter). Different nonlinear wave equations, such as the breaking wave, Korteweg-de Vries and Burgers equations, are...
Kofoed, Jens Peter; Frigaard, Peter; Sørensen, H. C.
1998-01-01
This paper concerns with the development of the wave energy converter (WEC) Wave Dragon. This WEC is based on the overtopping principle. An overview of the performed research done concerning the Wave Dragon over the past years is given, and the results of one of the more comprehensive studies......, concerning a hydraulic evaluation and optimisation of the geometry of the Wave Dragon, is presented. Furthermore, the plans for the future development projects are sketched....
Cosmological Acceleration from Gravitational Waves
Marochnik, Leonid
2015-01-01
It is shown that the classical gravitational waves of super-horizon wavelengths are able to form the de Sitter accelerated expansion of the empty (with no matter fields) Universe. The contemporary Universe is about 70% empty and asymptotically is going to become completely empty, so the effect caused by emptiness should be already very noticeable. It could manifest itself as the dark energy.
This book is dedicated to various aspects of electromagnetic wave theory and its applications in science and technology. The covered topics include the fundamental physics of electromagnetic waves, theory of electromagnetic wave propagation and scattering, methods of computational analysis......, material characterization, electromagnetic properties of plasma, analysis and applications of periodic structures and waveguide components, etc....
Towne, Dudley H
1988-01-01
This excellent undergraduate-level text emphasizes optics and acoustics, covering inductive derivation of the equation for transverse waves on a string, acoustic plane waves, boundary-value problems, polarization, three-dimensional waves and more. With numerous problems (solutions for about half). ""The material is superbly chosen and brilliantly written"" - Physics Today. Problems. Appendices.
Inertial quantum sensors using light and matter
Barrett, B.; Bertoldi, A.; Bouyer, P.
2016-05-01
The past few decades have seen dramatic progress in our ability to manipulate and coherently control matter-waves. Although the duality between particles and waves has been well tested since de Broglie introduced the matter-wave analog of the optical wavelength in 1924, manipulating atoms with a level of coherence that enables one to use these properties for precision measurements has only become possible with our ability to produce atomic samples exhibiting temperatures of only a few millionths of a degree above absolute zero. Since the initial experiments a few decades ago, the field of atom optics has developed in many ways, with both fundamental and applied significance. The exquisite control of matter waves offers the prospect of a new generation of force sensors exhibiting unprecedented sensitivity and accuracy, for applications from navigation and geophysics to tests of general relativity. Thanks to the latest developments in this field, the first commercial products using this quantum technology are now available. In the future, our ability to create large coherent ensembles of atoms will allow us an even more precise control of the matter-wave and the ability to create highly entangled states for non-classical atom interferometry.
In today’s globalized world, halal (meaning ‘permissible’ or ‘lawful’) is about more than food. Politics, power and ethics all play a role in the halal industry in setting new standards for production, trade, consumption and regulation. The question of how modern halal markets are constituted...... is illustrated by rich ethnographic case studies from a range of contexts, and consideration is given to both Muslim majority and minority societies. Halal Matters will be of interest to students and scholars working across the humanities and social sciences, including anthropology, sociology and religious...
Ramaswamy, Sriram
2017-05-01
The study of systems with sustained energy uptake and dissipation at the scale of the constituent particles is an area of central interest in nonequilibrium statistical physics. Identifying such systems as a distinct category—Active matter—unifies our understanding of autonomous collective movement in the living world and in some surprising inanimate imitations. In this article I present the active matter framework, briefly recall some early work, review our recent results on single-particle and collective behaviour, including experiments on active granular monolayers, and discuss new directions for the future.
A first course in vibrations and waves
Samiullah, Mohammad
2015-01-01
This book builds on introductory physics and emphasizes understanding of vibratory motion and waves based on first principles. The book is divided into three parts. Part I contains a preliminary chapter that serves as a review of relevant ideas of mechanics and complex numbers. Part II is devoted to a detailed discussion of vibrations of mechanical systems. This part covers a simple harmonic oscillator, coupled oscillators, normal coordinates, beaded string, continuous string, standing waves, and Fourier series. Part II ends with a presentation of stationary solutions of driven finite systems. Part III is concerned with waves. Here, the emphasis is on the discussion of common aspects of all types of waves. The applications to sound, electromagnetic, and matter waves are illustrated. The book also includes examples from water waves and electromagnetic waves on a transmission line. The emphasis of the book is to bring out the similarities among various types of waves. The book includes treatment of reflection a...
Neva Šlibar
1991-12-01
Full Text Available »Ich empfinde den Beruf eines Schriftstellres als den eines Berichterstatters, eines Chronisten. Ich bin ein Schreiber von Chroniken, mit literarischen Mitteln natürlich [...]« (A, 203. Dieses Selbstverständnis Christoph Heins, geäußert in einem lnterview für das Neue Deutschland vom 2./3. 12. 1989, enthalt mehr als das Bekenntnis zum Historischen, zum Schreiben »über mich und meine Welt« (ebda. als Leitthemen seines Iiterarischen Wirkens. Es ist eine Poetik in nuce. Im Gegensatz zum Historiker lebt der Chronist nämlich aus der Zeitgenossenschaft mit dem erzählten Geschehen, er befindet sich nach A. C. Danto folglich logisch in derselben Ordnung der Ereignisse, die er beschreibt• Es fehlt·ihm die restrospektiv wertende Sicht des Historikers, in Heins Worten: »Der Berichterstatter hat eigentlich nur etwas mitzuteilen und muß sich weitgehend der moralischen Wertung enthalten« (ebda.. Diese reduktionistische Postion bestimmt Heins Realismuskonzept, das keinen Anspruch auf epische Breite, Auktorialität und Beherrschbarkeit stellt, sowie keine konkreten Utopievorstellungen präsentiert. Weiters bestimmt sie die dominierende Bedeutung des Blickpunkts für die Wirklichkeitskonstruktion von Heins Welten, die Identitätsbildung seiner Figuren sowie die enggeführte Erzählhaltung (O, 157. Ablesbar ist sie gleichfalls an einer Motivik, die traditionellerweise Sichtverengung und Selbstbezogenheit zum Ausdruck bringt: Spiegel und blinde Scheiben, Fotoapparate und Kameras, Fotografieren und Sich-Spiegeln signalisieren vom Film inspirierte Schreibverfahren. Dieser (selbstbeschränkenden Position gilt es hier nachzugehen; ausgeklammert werden demnach bewußt aktuell geschichtliche und regional beschränkte, d. h. auf die DDR-eingegrenzte politische Interpretationsmöglichkeiten.
Sebastian Baden
2016-02-01
Full Text Available This contribution introduces to the video installation Black September (2002 by Swiss artist Christoph Draeger and presents statements of the artist given in an interview in 2012. Draeger collects media representations of disasters in order to reconfigure their inherent sensationalism later in his artworks. The video installation Black September consists of appropriated footage from a documentary movie and video sequences from a re-enactment of the historical events of September 5th 1972, the terrorist attack during the 20th Olympic Games in Munich. Even the artist himself gets involved in the play in his mimikry of a hostage-taker and terrorist. Thus he questions the conditions of the mutual constitution of cultural memory and collective memory. His video installation creates a “counter image” in reaction to the “omnipresent myth of terrorism”, generated by the tragedy of 9/11 and the media reports in its aftermath. Both terrorist attacks, in Munich 1972 and in New York 2001, mark a turning point in the visual dominance of terrorism. In the case of September 11th, the recurring images of the airplane-attacks and the explosion of the WTC, followed by its collapsing, symbolize the legacy of the “terror of attention”, that would affect every spectator. The video questions the limits of the “disaster zone” in fictional reality and mass media. The artwork re-creates central scenes of the event in 1972. It brings the terrorist action close to the spectator through emersive images, but technically obtains a critical distance through its mode of reflection upon the catastrophe.The installation Black September stimulates and simulates history and memory simultaneously. It fills the void of a traumatic narrative and tries to recapture the signs that have been unknown yet.
Carlos Augusto Rojas Arias
2009-06-01
Full Text Available The project of discovering America by Christopher Columbus is an enterprise of Modernity, understood as the modern mentality displayed in the capitalist system. Even though Columbus lived during the Renaissance period, the mentality carried in his project is closer to some modern philosophers such as Descartes and Hobbes, who from rationality and individualism constitute a change of time. The hypothesis that Columbus is a modern person is sustained with evidence in the reasons he explained to defend his project from the Spanish court and especially the final agreement, "the capitulation", in which rationality and individualism took precedence over divine or medieval considerations. The rationalist mentality of Columbus prefigures that from modern businessman who does not stitch without thimble.El descubrimiento de América, impulsado por Cristóbal Colón, es una empresa de la Modernidad, entendida esta como la mentalidad moderna desplegada en el sistema capitalista. Si bien es cierto que Colón, por la época en que vivió, se ubica dentro del Renacimiento, la mentalidad con que fue llevada a cabo su iniciativa está más cerca de modernos como Descartes y Hobbes, quienes, a partir de la racionalidad y el individualismo, configuran un cambio de época. La hipótesis de que Colón es un moderno se sustenta con muchas evidencias en las razones que construyó para defender su proyecto ante la corte española y especialmente en el acuerdo final, “la capitulación”, en donde la racionalidad y el individualismo priman sobre consideraciones divinas o medievales. La mentalidad racionalista de Colón prefigura la del empresario moderno que no da puntada sin dedal.
Sound Attenuation in Quark Matter Due to Pairing Fluctuations
Kerbikov, Boris
2016-01-01
The sound wave in dense quark matter is subject to strong absorption due to diquark field fluctuations above T critical. The result is another facet of Mandelshtam-Leontovich slow relaxation time theory.
Sound Attenuation in Quark Matter Due to Pairing Fluctuations
Kerbikov Boris
2016-01-01
Full Text Available The sound wave in dense quark matter is subject to strong absorption due to diquark field fluctuations above Tc. The result is another facet of Mandelshtam-Leontovich slow relaxation time theory.
Bird, Simeon; Muñoz, Julian B; Ali-Haïmoud, Yacine; Kamionkowski, Marc; Kovetz, Ely D; Raccanelli, Alvise; Riess, Adam G
2016-01-01
We consider the possibility that the black-hole (BH) binary detected by LIGO may be a signature of dark matter. Interestingly enough, there remains a window for masses $10\\,M_\\odot \\lesssim M_{\\rm bh} \\lesssim 100\\, M_\\odot$ where primordial black holes (PBHs) may constitute the dark matter. If two BHs in a galactic halo pass sufficiently close, they can radiate enough energy in gravitational waves to become gravitationally bound. The bound BHs will then rapidly spiral inward due to emission of gravitational radiation and ultimately merge. Uncertainties in the rate for such events arise from our imprecise knowledge of the phase-space structure of galactic halos on the smallest scales. Still, reasonable estimates span a range that overlaps the $2-53$ Gpc$^{-3}$ yr$^{-1}$ rate estimated from GW150914, thus raising the possibility that LIGO has detected PBH dark matter. PBH mergers are likely to be distributed spatially more like dark matter than luminous matter and have no optical nor neutrino counterparts. The...
Materials, matter and particles a brief history
Woolfson, Michael M
2010-01-01
This book traces the history of ideas about the nature of matter and also the way that mankind has used material resources that the world offers. Starting with the ideas of ancient civilizations that air, earth, fire and water were the basic ingredients of all matter, it traces the development of the science of chemistry beginning within the ranks of the alchemists. First, the idea of elements grew and then the atomic nature of matter was verified. Physicists had entered the scene, showing the nature of atoms in terms of fundamental particles and then introducing the concept of wave-particle d
King, B A
1999-01-01
This thesis is a compilation of five research projects completed while a graduate student at the University of Illinois at Chicago. The first is a study of the wavefunction at the origin for heavy quark-antiquark bound states. Within the context of nonrelativistic potential models, we obtain several formulas (with varying degrees of rigor) relating the wave functions at the origin of the cc¯, bc¯ and bb¯ S-wave quarkonium systems. One of our main results is a model-independent relation which seems to hold to within 3% for any reasonable choice of interquark potential and any choice of radial quantum number. The second project investigates possible bound states of heavy leptoquark- antiquark pairs (lepto-mesons) as well as leptoquark- antileptoquark pairs (leptoquarkonium). We study the spectra and decay widths of these states in the context of a nonrelativistic potential model which matches the recently calculated two-loop QCD potential at short distances to a successful phenomenolo...
Bel, Lluís
2017-01-01
I show that a very simple model in the context of Newtonian physics promoted to a first approximation of general relativity can mimic Dark matter and explain most of its intriguing properties. Namely: i) Dark matter is a halo associated to ordinary matter; ii) Dark matter does not interact with ordinary matter nor with itself; iii) Its influence grows with the size of the aggregate of ordinary matter that is considered, and iv) Dark matter influences the propagation of light.
Eisenberg, Bob
2016-01-01
Charges are everywhere because most atoms are charged. Chemical bonds are formed by electrons with their charge. Charges move and interact according to Maxwell's equations in space and in atoms where the equations of electrodynamics are embedded in Schroedinger's equation as the potential. Maxwell's equations are universal, valid inside atoms and between stars from times much shorter than those of atomic motion (0.1 femtoseconds) to years (32 mega-seconds). Maxwell's equations enforce the conservation of current. Analysis shows that the electric field can take on whatever value is needed to ensure conservation of current. The properties of matter rearrange themselves to satisfy Maxwell's equations and conservation of current. Conservation of current is as universal as Maxwell's equations themselves. Yet equations of electrodynamics find little place in the literature of material physics, chemistry, or biochemistry. Kinetic models of chemistry and Markov treatments of atomic motion are ordinary differential eq...
Holographic charge density waves
Donos, Aristomenis
2013-01-01
We show that strongly coupled holographic matter at finite charge density can exhibit charge density wave phases which spontaneously break translation invariance while preserving time-reversal and parity invariance. We show that such phases are possible within Einstein-Maxwell-dilaton theory in general spacetime dimensions. We also discuss related spatially modulated phases when there is an additional coupling to a second vector field, possibly with non-zero mass. We discuss how these constructions, and others, should be associated with novel spatially modulated ground states.
Holographic charge density waves
Donos, Aristomenis; Gauntlett, Jerome P.
2013-06-01
We show that strongly coupled holographic matter at finite charge density can exhibit charge density wave phases which spontaneously break translation invariance while preserving time-reversal and parity invariance. We show that such phases are possible within Einstein-Maxwell-dilaton theory in general spacetime dimensions. We also discuss related spatially modulated phases when there is an additional coupling to a second vector field, possibly with nonzero mass. We discuss how these constructions, and others, should be associated with novel spatially modulated ground states.
Directional detection of dark matter in universal bound states
Laha, Ranjan
2015-01-01
It has been suggested that several small-scale structure anomalies in $\\Lambda$CDM cosmology can be solved by strong self-interaction between dark matter particles. It was shown by Braaten and Hammer that the presence of a near threshold S-wave resonance can make the scattering cross section at nonrelativistic speeds come close to saturating the unitarity bound. This can result in the formation of a stable bound state of two asymmetric dark matter particles (which we call darkonium). Laha and Braaten studied the nuclear recoil energy spectrum in dark matter direct detection experiments due to this incident bound state. Here we study the angular recoil spectrum, and show that it is uniquely determined up to normalization by the S-wave scattering length. Observing this angular recoil spectrum in a dark matter directional detection experiment will uniquely determine many of the low-energy properties of dark matter independent of the underlying dark matter microphysics.
Kruse, Karsten
2017-01-01
Traveling waves propagating along surfaces play an important role for intracellular organization. Such waves can appear spontaneously in reaction-diffusion systems, but only few general criteria for their existence are known. Analyzing the dynamics of the Min proteins in Escherichia coli, Levine and Kessler (2016 New J. Phys. 18 122001) now identified a new mechanism for the emergence of traveling waves that relies on conservation laws. From their analysis one can expect traveling waves to be a generic feature of systems made of proteins that have a cytoplasmic and a membrane-bound state.
2016-01-01
We show the existence of a family of waves that share a common interesting property affecting the way they propagate and focus. These waves are a superposition of twin waves, which are conjugate to each other under inversion of the propagation direction. In analogy to holography, these twin "real" and "virtual" waves are related respectively to the converging and the diverging part of the beam and can be clearly visualized in real space at two distinct foci under the action of a focusing lens...
Wave-based liquid-interface metamaterials
Francois, N; Xia, H; Punzmann, H; Fontana, P W; Shats, M
2017-01-01
The control of matter motion at liquid–gas interfaces opens an opportunity to create two-dimensional materials with remotely tunable properties. In analogy with optical lattices used in ultra-cold atom physics, such materials can be created by a wave field capable of dynamically guiding matter into periodic spatial structures. Here we show experimentally that such structures can be realized at the macroscopic scale on a liquid surface by using rotating waves. The wave angular momentum is transferred to floating micro-particles, guiding them along closed trajectories. These orbits form stable spatially periodic patterns, the unit cells of a two-dimensional wave-based material. Such dynamic patterns, a mirror image of the concept of metamaterials, are scalable and biocompatible. They can be used in assembly applications, conversion of wave energy into mean two-dimensional flows and for organising motion of active swimmers. PMID:28181490
Holographic vortices in the presence of dark matter sector
Rogatko, Marek
2015-01-01
The {\\it dark matter} seem to be an inevitable ingredient of the total matter configuration in the Universe and the knowledge how the {\\it dark matter} affects the properties of superconductors is of vital importance for the experiments aimed at its direct detection. The homogeneous magnetic field acting perpendicularly to the surface of (2+1) dimensional s-wave holographic superconductor in the theory with {\\it dark matter} sector has been modeled by the additional $U(1)$-gauge field representing dark matter and coupled to the Maxwell one. As expected the free energy for the vortex configuration turns out to be negative. Importantly its value is lower in the presence of {\\it dark matter} sector. This feature can explain why in the Early Universe first the web of {\\it dark matter} appeared and next on these gratings the ordinary matter forming cluster of galaxies has formed.
Kaivarainen, A
2001-01-01
The original mechanism of bivacuum mediated Mind-Matter and Mind-Mind interaction, proposed here, is based on the following stages of long term efforts: New dynamic models of bivacuum, sub-elementary particles and corpuscle-wave [C-W] duality, as a background of Superunification; New Hierarchic theory of liquids and solids; New Hierarchic model of elementary act of consciousness; Virtual Replica (VR)of matter, including living organisms, in bivacuum; The distant resonant [Mind-Bivacuum-Matter] and [Mind-Bivacuum-Mind] interaction, mediated by Bivacuum oscillation (BvO, accompanied by virtual particles/antiparticles pressure oscillation. The latter factor is related to oscillation of vacuum permittivity and permeability. The virtual replica (VR) of condensed matter (living organisms in private case), may influence the properties of virtual pressure of bivacuum in following manner: 1) changing the amplitude of virtual pressure waves (VPW) in-phase with Bivacuum oscillations (BvO). This factor is dependent on fr...
Initial State Radiation in Majorana Dark Matter Annihilations
Ciafaloni, Paolo; Comelli, Denis; De Simone, Andrea; Riotto, Antonio; Urbano, Alfredo
2011-01-01
The cross section for a Majorana Dark Matter particle annihilating into light fermions is helicity suppressed. We show that, if the Dark Matter is the neutral Majorana component of a multiplet which is charged under the electroweak interactions of the Standard Model, the emission of gauge bosons from the initial state lifts the suppression and allows an s-wave annihilation. The resulting energy spectra of stable Standard Model particles are importantly affected. This has an impact on indirect searches for Dark Matter.
Fukushima, Kenji
2014-01-01
We summarize recent developments in identifying the ground state of dense baryonic matter and beyond. The topics include deconfinement from baryonic matter to quark matter, a diquark mixture, topological effect coupled with chirality and density, and inhomogeneous chiral condensates.
Gillian Warner-Søderholm
2012-12-01
Full Text Available Whether managers are concerned with financial issues, marketing, or human resource management (HRM, cultural values and practices do matter. The purpose of this article is to understand Norwegian managers’ cultural values within the cross-cultural landscape of her neighbors in the “Scandinavian cluster.” Clearly, subtle but disturbing differences may surface even when representatives from similar cultures work together. As a follow on from the GLOBE project, data based on the GLOBE instrument were collected on culture and communication values in Norway from 710 Norwegian middle managers for this present study. Although the Scandinavian cultures appear ostensibly similar, the results illustrate that research can reveal subtle but important cultural differences in nations that are similar yet dissimilar. All three Scandinavian societies appear intrinsically egalitarian; they appear to value low Power Distance, directness, and consensus in decision making and to promote Gender Egalitarianism. Nevertheless, there are significant differences in the degrees of commitment to these values by each individual Scandinavian partner. These differences need to be understood and appreciated to avoid misunderstandings.
Gierl, Martin
2010-01-01
In the middle of the eighteenth century, Carl von Linné, Johann Christoph Gatterer, and Christian Wilhelm Büttner attempted to realize the old idea of deciphering the alphabet of the world, which Francis Bacon had raised as a general postulate of science. This article describes these attempts and their interrelations. Linné used the model of the alphabet to classify plants according to the characters of this fruiting body. Gatterer, one of the leading German historians during the Enlightenment, adopted the botanical method of classification by genus and species to classify the history of scripts. He used the forms of the alphabetic characters to measure the age of manuscripts and to map the process of history as a genealogy of culture. Gatterer collaborated closely with Büttner, the first Göttingen professor of natural history. Büttner constructed a general alphabet of languages which connected the phonetics of language with the historically known alphabets. Early on, diplomatics and ethnography combined the natural order of natural history and the cultural order of the alphabet with the attempt to register development and to document development by the evolution of forms. Based on the shared model of the alphabet and on the common necessity to classify their empirical material, natural history and the description of culture were related attempts in the middle of the eighteenth century to comprehend the alphabetically organized nature and a naturally ordered culture.
King, Beurett Alexander, III
This thesis is a compilation of five research projects completed while a graduate student at the University of Illinois at Chicago. The first is a study of the wavefunction at the origin for heavy quark-antiquark bound states. Within the context of nonrelativistic potential models, we obtain several formulas (with varying degrees of rigor) relating the wave functions at the origin of the cc¯, bc¯ and bb¯ S-wave quarkonium systems. One of our main results is a model-independent relation which seems to hold to within 3% for any reasonable choice of interquark potential and any choice of radial quantum number. The second project investigates possible bound states of heavy leptoquark- antiquark pairs (lepto-mesons) as well as leptoquark- antileptoquark pairs (leptoquarkonium). We study the spectra and decay widths of these states in the context of a nonrelativistic potential model which matches the recently calculated two-loop QCD potential at short distances to a successful phenomenological quarkonium potential at intermediate distances. We also compute the expected number of events for these states at future colliders. The third project is a study of the possible production of a bound state of strongly coupled constituents carrying lepton number at an e- e- collider. We show that under reasonable assumptions, the existence of one leptogluon flavor of appropriate mass can give rise to sizeable ``leptoglueball'' production rates and observable resonance peaks. In the fourth project, we give a definition of pure Yang-Mills theories on space- times which are arbitrary 2D cell complexes. As in the manifold case, these models are exactly solvable for any gauge group G, and are topological quantum field theories if G is finite, or for any G in the limit as the space- time area goes to zero. The final topic of this thesis is a discussion of a recent classification of all forms of unitary quantum statistics that satisfy a strong version of the cluster decomposition
Tedd, James; Kofoed, Jens Peter; Friis-Madsen, Erik
2008-01-01
Since March 2003 a prototype of Wave Dragon has been tested in an inland sea in Denmark. This has been a great success with all subsystems tested and improved through working in an offshore environment. The project has proved the Wave Dragon device and has enabled the next stage, a production sized...
Tedd, James; Kofoed, Jens Peter; Friis-Madsen, Erik;
2008-01-01
Since March 2003 a prototype of Wave Dragon has been tested in an inland sea in Denmark. This has been a great success with all subsystems tested and improved through working in an offshore environment. The project has proved the Wave Dragon device and has enabled the next stage, a production sized...
Kramer, Morten; Brorsen, Michael; Frigaard, Peter
Nærværende rapport beskriver numeriske beregninger af den hydrodynamiske interaktion mellem 5 flydere i bølgeenergianlægget Wave Star.......Nærværende rapport beskriver numeriske beregninger af den hydrodynamiske interaktion mellem 5 flydere i bølgeenergianlægget Wave Star....
Splinter, Susan
2011-01-01
The medical institutions of Nuremberg were established quite early. The Collegium medicum were already founded in 1592. Though this board held responsibility for the supervision of pharmacies, the creation of Medizinalordnungen (medical legislations) and also had advisory functions, the physicians did not succeed in winning a prominent position. The spheres of competence between the different groups of medical practitioners were not yet clearly defined. Nevertheless the daily work of the practitioner Johann Christoph Götz (1688-1733) was going smoothly due to his cooperation with other doctors, surgeons, midwives and pharmacists.
Christov, Ivan C
2012-01-01
In classical continuum physics, a wave is a mechanical disturbance. Whether the disturbance is stationary or traveling and whether it is caused by the motion of atoms and molecules or the vibration of a lattice structure, a wave can be understood as a specific type of solution of an appropriate mathematical equation modeling the underlying physics. Typical models consist of partial differential equations that exhibit certain general properties, e.g., hyperbolicity. This, in turn, leads to the possibility of wave solutions. Various analytical techniques (integral transforms, complex variables, reduction to ordinary differential equations, etc.) are available to find wave solutions of linear partial differential equations. Furthermore, linear hyperbolic equations with higher-order derivatives provide the mathematical underpinning of the phenomenon of dispersion, i.e., the dependence of a wave's phase speed on its wavenumber. For systems of nonlinear first-order hyperbolic equations, there also exists a general ...
Kalliadasis, Serafim
2007-01-01
A detailed overview and comprehensive analysis of the main theoretical and experimental advances on free surface thin film and jet flows of soft matter is given. At the theoretical front the book outlines the basic equations and boundary conditions and the derivation of low-dimensional models for the evolution of the free surface. Such models include long-wave expansions and equations of the boundary layer type and are analyzed via linear stability analysis, weakly nonlinear theories and strongly nonlinear analysis including construction of stationary periodic and solitary wave and similarity solutions. At the experimental front a variety of very recent experimental developments is outlined and the link between theory and experiments is illustrated. Such experiments include spreading drops and bubbles, imbibitions, singularity formation at interfaces and experimental characterization of thin films using atomic force microscopy, ellipsometry and contact angle measurements and analysis of patterns using Minkows...
Waves, damped wave and observation
Phung, Kim Dang
2009-01-01
We consider the wave equation in a bounded domain (eventually convex). Two kinds of inequality are described when occurs trapped ray. Applications to control theory are given. First, we link such kind of estimate with the damped wave equation and its decay rate. Next, we describe the design of an approximate control function by an iterative time reversal method.
Fritts, David
1987-02-01
Gravity waves contributed to the establishment of the thermal structure, small scale (80 to 100 km) fluctuations in velocity (50 to 80 m/sec) and density (20 to 30%, 0 to peak). Dominant gravity wave spectrum in the middle atmosphere: x-scale, less than 100 km; z-scale, greater than 10 km; t-scale, less than 2 hr. Theorists are beginning to understand middle atmosphere motions. There are two classes: Planetary waves and equatorial motions, gravity waves and tidal motions. The former give rise to variability at large scales, which may alter apparent mean structure. Effects include density and velocity fluctuations, induced mean motions, and stratospheric warmings which lead to the breakup of the polar vortex and cooling of the mesosphere. On this scale are also equatorial quasi-biennial and semi-annual oscillations. Gravity wave and tidal motions produce large rms fluctuations in density and velocity. The magnitude of the density fluctuations compared to the mean density is of the order of the vertical wavelength, which grows with height. Relative density fluctuations are less than, or of the order of 30% below the mesopause. Such motions may cause significant and variable convection, and wind shear. There is a strong seasonal variation in gravity wave amplitude. Additional observations are needed to address and quantify mean and fluctuation statistics of both density and mean velocity, variability of the mean and fluctuations, and to identify dominant gravity wave scales and sources as well as causes of variability, both temporal and geographic.
Bertoin, Jean; Jacod, Jean; Klüppelberg, Claudia
2010-01-01
This is the first volume of a subseries of the Lecture Notes in Mathematics which will appear randomly over the next years. Each volume will describe some important topic in the theory or applications of Lévy processes and pay tribute to the state of the art of this rapidly evolving subject with special emphasis on the non-Brownian world. The three expository articles of this first volume have been chosen to reflect the breadth of the area of Lévy processes. The first article by Ken-iti Sato characterizes extensions of the class of selfdecomposable distributions on R^d. The second article by Thomas Duquesne discusses Hausdorff and packing measures of stable trees. The third article by Oleg Reichmann and Christoph Schwab presents numerical solutions to Kolmogoroff equations, which arise for instance in financial engineering, when Lévy or additive processes model the dynamics of the risky assets.
Tedd, James; Kofoed, Jens Peter; Knapp, W.
2006-01-01
Wave Dragon is a floating wave energy converter working by extracting energy principally by means of overtopping of waves into a reservoir. A 1:4.5 scale prototype has been sea tested for 20 months. This paper presents results from testing, experiences gained and developments made during...... this extended period. The prototype is highly instrumented. The overtopping characteristic and the power produced are presented here. This has enabled comparison between the prototype and earlier results from both laboratory model and computer simulation. This gives the optimal operating point and the expected...
Robinett, R.W
2004-03-01
The numerical prediction, theoretical analysis, and experimental verification of the phenomenon of wave packet revivals in quantum systems has flourished over the last decade and a half. Quantum revivals are characterized by initially localized quantum states which have a short-term, quasi-classical time evolution, which then can spread significantly over several orbits, only to reform later in the form of a quantum revival in which the spreading reverses itself, the wave packet relocalizes, and the semi-classical periodicity is once again evident. Relocalization of the initial wave packet into a number of smaller copies of the initial packet ('minipackets' or 'clones') is also possible, giving rise to fractional revivals. Systems exhibiting such behavior are a fundamental realization of time-dependent interference phenomena for bound states with quantized energies in quantum mechanics and are therefore of wide interest in the physics and chemistry communities. We review the theoretical machinery of quantum wave packet construction leading to the existence of revivals and fractional revivals, in systems with one (or more) quantum number(s), as well as discussing how information on the classical period and revival time is encoded in the energy eigenvalue spectrum. We discuss a number of one-dimensional model systems which exhibit revival behavior, including the infinite well, the quantum bouncer, and others, as well as several two-dimensional integrable quantum billiard systems. Finally, we briefly review the experimental evidence for wave packet revivals in atomic, molecular, and other systems, and related revival phenomena in condensed matter and optical systems.
Robinett, R. W.
2004-03-01
The numerical prediction, theoretical analysis, and experimental verification of the phenomenon of wave packet revivals in quantum systems has flourished over the last decade and a half. Quantum revivals are characterized by initially localized quantum states which have a short-term, quasi-classical time evolution, which then can spread significantly over several orbits, only to reform later in the form of a quantum revival in which the spreading reverses itself, the wave packet relocalizes, and the semi-classical periodicity is once again evident. Relocalization of the initial wave packet into a number of smaller copies of the initial packet (‘minipackets’ or ‘clones’) is also possible, giving rise to fractional revivals. Systems exhibiting such behavior are a fundamental realization of time-dependent interference phenomena for bound states with quantized energies in quantum mechanics and are therefore of wide interest in the physics and chemistry communities. We review the theoretical machinery of quantum wave packet construction leading to the existence of revivals and fractional revivals, in systems with one (or more) quantum number(s), as well as discussing how information on the classical period and revival time is encoded in the energy eigenvalue spectrum. We discuss a number of one-dimensional model systems which exhibit revival behavior, including the infinite well, the quantum bouncer, and others, as well as several two-dimensional integrable quantum billiard systems. Finally, we briefly review the experimental evidence for wave packet revivals in atomic, molecular, and other systems, and related revival phenomena in condensed matter and optical systems.
Papazoglou, Dimitris G; Tzortzakis, Stelios
2016-01-01
We show the existence of a family of waves that share a common interesting property affecting the way they propagate and focus. These waves are a superposition of twin waves, which are conjugate to each other under inversion of the propagation direction. In analogy to holography, these twin "real" and "virtual" waves are related respectively to the converging and the diverging part of the beam and can be clearly visualized in real space at two distinct foci under the action of a focusing lens. Analytic formulas for the intensity distribution after focusing are derived, while numerical and experimental demonstrations are given for some of the most interesting members of this family, the accelerating Airy and ring-Airy beams.
Kramer, Morten; Frigaard, Peter
Nærværende rapport beskriver modelforsøg udført på Aalborg Universitet, Institut for Byggeri og Anlæg med bølgeenergianlæget Wave Star.......Nærværende rapport beskriver modelforsøg udført på Aalborg Universitet, Institut for Byggeri og Anlæg med bølgeenergianlæget Wave Star....
Kramer, Morten; Andersen, Thomas Lykke
Nærværende rapport beskriver modelforsøg udført på Aalborg Universitet, Institut for Vand, Jord og Miljøteknik med bølgeenergianlægget Wave Star.......Nærværende rapport beskriver modelforsøg udført på Aalborg Universitet, Institut for Vand, Jord og Miljøteknik med bølgeenergianlægget Wave Star....
A Máquina Teórica: O Discurso de Christopher Norris sobre o Pós-Modernismo na Década de Noventa
Adam Sharman
1997-10-01
Full Text Available opresente ensaio oferece uma exegese crítica dos sete livros que, até o final de 1997, o teórico e crítico britânico Christopher Norman dedicou ao pós-modernismo, considerando-se que a temática de Norris é a teoria pósmodernista, não os artefatos culturais ou processos pósmodernistas pelos quais ele demonstra pouco interesse. Nessa trajetória, são entrelaçados os fios de diversas questões: o entendimento de Norris do pós-modernismo; as objeções que ele faz à teoria pós-modernista; o teor de sua discordância de pensadores como Baudrillard com relação à Guerra do Golfo; a nota de desalento que pauta sua visão do pós-modernismo; o impacto do contexto político de direita de Margaret Thatcher sobre sua visão pessimista dos intelectuais pós-modernistas no início da década. Sobretudo, o ensaio rastreia a crítica reiterada de Norris à excessiva extensão conferida à lingüística saussureana, na sua opinião, a raiz de um mal-elaborado "relativismo cultural", bem como seu amplo comentário sobre o afastamento de Michel Foucault do pensamento de Kant. Norris crê que esse encontro ilustra, de forma exemplar, o afastamento pós-modernista dos valores iluministas de verdade, crítica e razão universal, cujo corolário, para ele, é a eliminação de qualquer vinculação, baseada em princípios, entre a prática intelectual e o domínio ético-político. O ensaio oferece, paralelamente, um número de críticas a Norris (inclusive seu hábito de processar diversas posições numa máquina teórica abstrata e imperdoável, aiJ ressaltar as muitas alternativas à teoria pós-modernista que ele explora (filosofias pós-analíticas do significado, filosofia da ciência, realismo causal, a desconstrução de Derrida e de Man. O ensaio conclui estabelecendo uma distinção entre relatividade e relativismo e enfatizando que também a epistemologia necessita de uma ética e de uma responsabilidade -com relação aos textos
Needham, Charles E
2010-01-01
The primary purpose of this text is to document many of the lessons that have been learned during the author’s more than forty years in the field of blast and shock. The writing therefore takes on an historical perspective, in some sense, because it follows the author’s experience. The book deals with blast waves propagating in fluids or materials that can be treated as fluids. It begins by distinguishing between blast waves and the more general category of shock waves. It then examines several ways of generating blast waves, considering the propagation of blast waves in one, two and three dimensions as well as through the real atmosphere. One section treats the propagation of shocks in layered gases in a more detailed manner. The book also details the interaction of shock waves with structures in particular reflections, progressing from simple to complex geometries, including planar structures, two-dimensional structures such as ramps or wedges, reflections from heights of burst, and three-dimensional st...
Wave chaotic experiments and models for complicated wave scattering systems
Yeh, Jen-Hao
Wave scattering in a complicated environment is a common challenge in many engineering fields because the complexity makes exact solutions impractical to find, and the sensitivity to detail in the short-wavelength limit makes a numerical solution relevant only to a specific realization. On the other hand, wave chaos offers a statistical approach to understand the properties of complicated wave systems through the use of random matrix theory (RMT). A bridge between the theory and practical applications is the random coupling model (RCM) which connects the universal features predicted by RMT and the specific details of a real wave scattering system. The RCM gives a complete model for many wave properties and is beneficial for many physical and engineering fields that involve complicated wave scattering systems. One major contribution of this dissertation is that I have utilized three microwave systems to thoroughly test the RCM in complicated wave systems with varied loss, including a cryogenic system with a superconducting microwave cavity for testing the extremely-low-loss case. I have also experimentally tested an extension of the RCM that includes short-orbit corrections. Another novel result is development of a complete model based on the RCM for the fading phenomenon extensively studied in the wireless communication fields. This fading model encompasses the traditional fading models as its high-loss limit case and further predicts the fading statistics in the low-loss limit. This model provides the first physical explanation for the fitting parameters used in fading models. I have also applied the RCM to additional experimental wave properties of a complicated wave system, such as the impedance matrix, the scattering matrix, the variance ratio, and the thermopower. These predictions are significant for nuclear scattering, atomic physics, quantum transport in condensed matter systems, electromagnetics, acoustics, geophysics, etc.
Book review: Rogue waves in the ocean
Geist, Eric L.
2011-01-01
Rogue Waves in the Ocean (2009) is a follow-on text to Extreme Ocean Waves (2008) edited by Pelinovsky and Kharif, both published by Springer. Unlike the earlier text, which is a compilation of papers on a variety of extreme waves that was the subject of a scientific conference in 2007, Rogues Waves in the Ocean is written, rather than edited, by Kharif, Pelinovsky, and Slunyaev and is focused on rogue waves in particular. The book consists of six chapters covering 216 pages. As the subject matter of each chapter is distinct, references appear at the end of each chapter rather than at the end of the book. The preface shows how each of the chapters relates to the larger study of rogue waves. The result is a book with a nice mix of eyewitness observations, physical theory, and statistics.
Mead, Carver
2015-01-01
Gravitational coupling of the propagation four-vectors of matter wave functions is formulated in flat space-time. Coupling at the momentum level rather than at the "force-law" level greatly simplifies many calculations. This locally Lorentz-invariant approach (G4v) treats electromagnetic and gravitational coupling on an equal footing. Classical mechanics emerges from the incoherent aggregation of matter wave functions. The theory reproduces, to first order beyond Newton, the standard GR results for Gravity-Probe B, deflection of light by massive bodies, precession of orbits, gravitational red shift, and total gravitational-wave energy radiated by a circular binary system. Its predictions of total radiated energy from highly eccentric Kepler systems are slightly larger than those of similar GR treatments. G4v predictions differ markedly from those of GR for the gravitational-wave radiation patterns from rotating massive systems, and for the LIGO antenna pattern. The predicted antenna patterns have been shown t...
Frigaard, Peter; Høgedal, Michael; Christensen, Morten
The intention of this manual is to provide some formulas and techniques which can be used for generating waves in hydraulic laboratories. Both long crested waves (2-D waves) and short crested waves (3-D waves) are considered....
Frigaard, Peter; Høgedal, Michael; Christensen, Morten
1993-01-01
The intention of this manual is to provide some formulas and techniques which can be used for generating waves in hydraulic laboratories. Both long crested waves (2-D waves) and short crested waves (3-D waves) are considered.
Slow wave propagation in soft adhesive interfaces.
Viswanathan, Koushik; Sundaram, Narayan K; Chandrasekar, Srinivasan
2016-11-16
Stick-slip in sliding of soft adhesive surfaces has long been associated with the propagation of Schallamach waves, a type of slow surface wave. Recently it was demonstrated using in situ experiments that two other kinds of slow waves-separation pulses and slip pulses-also mediate stick-slip (Viswanathan et al., Soft Matter, 2016, 12, 5265-5275). While separation pulses, like Schallamach waves, involve local interface detachment, slip pulses are moving stress fronts with no detachment. Here, we present a theoretical analysis of the propagation of these three waves in a linear elastodynamics framework. Different boundary conditions apply depending on whether or not local interface detachment occurs. It is shown that the interface dynamics accompanying slow waves is governed by a system of integral equations. Closed-form analytical expressions are obtained for the interfacial pressure, shear stress, displacements and velocities. Separation pulses and Schallamach waves emerge naturally as wave solutions of the integral equations, with oppositely oriented directions of propagation. Wave propagation is found to be stable in the stress regime where linearized elasticity is a physically valid approximation. Interestingly, the analysis reveals that slow traveling wave solutions are not possible in a Coulomb friction framework for slip pulses. The theory provides a unified picture of stick-slip dynamics and slow wave propagation in adhesive contacts, consistent with experimental observations.
Nonlinear wave-wave interactions and wedge waves
Ray Q.Lin; Will Perrie
2005-01-01
A tetrad mechanism for exciting long waves,for example edge waves,is described based on nonlinear resonant wave-wave interactions.In this mechanism,resonant interactions pass energy to an edge wave,from the three participating gravity waves.The estimated action flux into the edge wave can be orders of magnitude greater than the transfer fluxes derived from other competing mechanisms,such as triad interactions.Moreover,the numerical results show that the actual transfer rates into the edge wave from the three participating gravity waves are two-to three- orders of magnitude greater than bottom friction.
Matter and twin matter in bimetric MOND
Milgrom, Mordehai
2010-01-01
Bimetric MOND (BIMOND) theories, propounded recently, predict peculiar gravitational interactions between matter and twin matter (TM). Twin matter is hypothetical matter that might couple directly only to the second metric of the theory. Considerations of cosmology in the BIMOND framework suggest that such TM might exist and copy matter in its attributes. Here I investigate the indirect interactions that BIMOND theories predict between nonrelativistic masses of matter and TM. The most salient result is that in the deep-MOND regime of the matter-TM-symmetric theories, TM behaves as if it has a negative gravitational mass. To wit, interaction within each sector is attractive MOND gravity, but between matter and TM it is repulsive MOND gravity. In the high-acceleration regime, the interaction depends on a parameter, beta. For the favored value beta=1, matter and TM do not interact in this regime; for beta1 they repel each other. Such interactions may have substantial ramifications for all aspects of structure fo...
Dynamical Space-Time and Gravitational Waves
van Holten, J W
2016-01-01
According to General Relativity gravity is the result of the interaction between matter and space-time geometry. In this interaction space-time geometry itself is dynamical: it can store and transport energy and momentum in the form of gravitational waves. We give an introductory account of this phenomenon and discuss how the observation of gravitational waves may open up a fundamentally new window on the universe.
Inversion of an Atomic Wave Packet in a Circularly Polarized Electromagnetic Wave
ZENG Gao-Jian
2001-01-01
We study behavior of an atomic wave packet in a circularly polarized electromagnetic wave, and particularly calculate the atomic inversion of the wave packet. A general method of calculation is presented. The results are interesting. For example, if the wave packet is very narrow or/and the interaction is very strong, no matter the atom is initially in its ground state or excited state, the atomic inversion approaches zero as time approaches infinity. If the atom is initially in its ground state and excited state with the probability 1/2 respectively, and if the momentum density is an even function, then the atomic inversion equals zero at any time.``
Resonance Van Hove singularities in wave kinetics
Shi, Yi-Kang; Eyink, Gregory L.
2016-10-01
Wave kinetic theory has been developed to describe the statistical dynamics of weakly nonlinear, dispersive waves. However, we show that systems which are generally dispersive can have resonant sets of wave modes with identical group velocities, leading to a local breakdown of dispersivity. This shows up as a geometric singularity of the resonant manifold and possibly as an infinite phase measure in the collision integral. Such singularities occur widely for classical wave systems, including acoustical waves, Rossby waves, helical waves in rotating fluids, light waves in nonlinear optics and also in quantum transport, e.g. kinetics of electron-hole excitations (matter waves) in graphene. These singularities are the exact analogue of the critical points found by Van Hove in 1953 for phonon dispersion relations in crystals. The importance of these singularities in wave kinetics depends on the dimension of phase space D =(N - 2) d (d physical space dimension, N the number of waves in resonance) and the degree of degeneracy δ of the critical points. Following Van Hove, we show that non-degenerate singularities lead to finite phase measures for D > 2 but produce divergences when D ≤ 2 and possible breakdown of wave kinetics if the collision integral itself becomes too large (or even infinite). Similar divergences and possible breakdown can occur for degenerate singularities, when D - δ ≤ 2, as we find for several physical examples, including electron-hole kinetics in graphene. When the standard kinetic equation breaks down, then one must develop a new singular wave kinetics. We discuss approaches from pioneering 1971 work of Newell & Aucoin on multi-scale perturbation theory for acoustic waves and field-theoretic methods based on exact Schwinger-Dyson integral equations for the wave dynamics.
Sculpturing the Electron Wave Function
Shiloh, Roy; Lilach, Yigal; Arie, Ady
2014-01-01
Coherent electrons such as those in electron microscopes, exhibit wave phenomena and may be described by the paraxial wave equation. In analogy to light-waves, governed by the same equation, these electrons share many of the fundamental traits and dynamics of photons. Today, spatial manipulation of electron beams is achieved mainly using electrostatic and magnetic fields. Other demonstrations include simple phase-plates and holographic masks based on binary diffraction gratings. Altering the spatial profile of the beam may be proven useful in many fields incorporating phase microscopy, electron holography, and electron-matter interactions. These methods, however, are fundamentally limited due to energy distribution to undesired diffraction orders as well as by their binary construction. Here we present a new method in electron-optics for arbitrarily shaping of electron beams, by precisely controlling an engineered pattern of thicknesses on a thin-membrane, thereby molding the spatial phase of the electron wav...
Relativistic simulations of compact object mergers for nucleonic matter and strange quark matter
Bauswein, Andreas Ottmar
2010-01-29
Under the assumption that the energy of the ground state of 3-flavor quark matter is lower than the one of nucleonic matter, the compact stellar remnants of supernova explosions are composed of this quark matter. Because of the appearance of strange quarks, such objects are called strange stars. Considering their observational features, strange stars are very similar to neutron stars made of nucleonic matter, and therefore observations cannot exclude the existence of strange stars. This thesis introduces a new method for simulating mergers of compact stars and black holes within a general relativistic framework. The main goal of the present work is the investigation of the question, whether the coalescence of two strange stars in a binary system yields observational signatures that allow one to distinguish them from colliding neutron stars. In this context the gravitational-wave signals are analyzed. It is found that in general the characteristic frequencies in the gravitational-wave spectra are higher for strange stars. Moreover, the amount of matter that becomes gravitationally unbound during the merging is determined. The detection of ejecta of strange star mergers as potential component of cosmic ray flux could serve as a proof of the existence of strange quark matter. (orig.)
Selection Rule for Enhanced Dark Matter Annihilation
Das, Anirban; Dasgupta, Basudeb
2017-06-01
We point out a selection rule for enhancement (suppression) of odd (even) partial waves of dark matter coannihilation or annihilation using the Sommerfeld effect. Using this, the usually velocity-suppressed p -wave annihilation can dominate the annihilation signals in the present Universe. The selection mechanism is a manifestation of the exchange symmetry of identical incoming particles, and generic for multistate DM with off-diagonal long-range interactions. As a consequence, the relic and late-time annihilation rates are parametrically different and a distinctive phenomenology, with large but strongly velocity-dependent annihilation rates, is predicted.
Combustion of nuclear matter into strange matter
Lugones, G. (Departamento di Fisica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, (1900) La Plata (Argentina)); Benvenuto, O.G.; Vucetich, H. (Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N, (1900) La Plata (Argentina))
1994-11-15
We study the properties of the combustion of pure neutron matter into strange matter in the framework of relativistic hydrodynamical theory of combustion. Because of the uncertainties in the actual properties of neutron matter, we employ the free neutron, Bethe-Johnson, Lattimer-Ravenhall, and Walecka equations of state and for strange matter we adopt the MIT bag model approximation. We find that combustion is possible for free neutron, Bethe-Johnson, and Lattimer-Ravenhall neutron matter but not for Walecka neutron matter. We interpret these results using a simple polytropic approximation showing that there exists a general flammability condition. We also study the burning of neutron matter into strange matter in a pipe showing that hydrodynamics demands flames faster than predicted by kinetics by several orders of magnitude, implying that the flame must be turbulent. Also the conditions for the deflagration to detonation transition are addressed, showing that in a pipe some of them are satisfied, strongly suggesting that the actual combustion mode should be detonation.
Shallow Water Waves and Solitary Waves
Hereman, Willy
2013-01-01
Encyclopedic article covering shallow water wave models used in oceanography and atmospheric science. Sections: Definition of the Subject; Introduction and Historical Perspective; Completely Integrable Shallow Water Wave Equations; Shallow Water Wave Equations of Geophysical Fluid Dynamics; Computation of Solitary Wave Solutions; Numerical Methods; Water Wave Experiments and Observations; Future Directions, and Bibliography.
Asorey, Manuel
2016-01-01
An old branch of mathematics, Topology, has opened the road to the discovery of new phases of matter. A hidden topology in the energy spectrum is the key for novel conducting/insulating properties of topological matter.
Avakyan, R.M.; Sarkisyan, A.V.
1987-07-01
The properties of degenerate stellar matter in the region of nuclear densities are considered. The threshold of the transition of the electron-nucleus phase to the state of continuous nuclear matter is found.
... Term(s): Teachers / NIDA Teaching Guide / Mind Over Matter Teaching Guide and Series / Cocaine Print Mind Over Matter: Cocaine Order Free Publication in: English Spanish Download PDF 806.08 KB Cocaine is ...
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Wave and particle in molecular interference lithography.
Juffmann, Thomas; Truppe, Stefan; Geyer, Philipp; Major, András G; Deachapunya, Sarayut; Ulbricht, Hendrik; Arndt, Markus
2009-12-31
The wave-particle duality of massive objects is a cornerstone of quantum physics and a key property of many modern tools such as electron microscopy, neutron diffraction or atom interferometry. Here we report on the first experimental demonstration of quantum interference lithography with complex molecules. Molecular matter-wave interference patterns are deposited onto a reconstructed Si(111) 7x7 surface and imaged using scanning tunneling microscopy. Thereby both the particle and the quantum wave character of the molecules can be visualized in one and the same image. This new approach to nanolithography therefore also represents a sensitive new detection scheme for quantum interference experiments.
Wave and Particle in Molecular Interference Lithography
Juffmann, Thomas; Geyer, Philipp; Major, Andras G; Deachapunya, Sarayut; Ulbricht, Hendrik; Arndt, Markus; 10.1103/PhysRevLett.103.263601
2010-01-01
The wave-particle duality of massive objects is a cornerstone of quantum physics and a key property of many modern tools such as electron microscopy, neutron diffraction or atom interferometry. Here we report on the first experimental demonstration of quantum interference lithography with complex molecules. Molecular matter-wave interference patterns are deposited onto a reconstructed Si(111) 7x7 surface and imaged using scanning tunneling microscopy. Thereby both the particle and the quantum wave character of the molecules can be visualized in one and the same image. This new approach to nanolithography therefore also represents a sensitive new detection scheme for quantum interference experiments.
Nicolas, Maxime
2016-01-01
Engineering school; This course is designed for students of Polytech Marseille, engineering school. It covers first the physics of vibration of the harmonic oscillator with damping and forcing, coupled oscillators. After a presentation of the wave equation, the vibration of strings, beams and membranes are studied.
Kramer, Morten; Frigaard, Peter
På foranledning af Löwenmark F.R.I, er der udført numeriske beregninger af Wave Dragons (herefter WD) armes effektivitet for forskellige geometriske udformninger. 5 geometriske modeller, hvor WD's arme er forkortet/forlænget er undersøgt for 3 forskellige drejninger af armene. I alt er 15...
Kramer, Morten; Frigaard, Peter
På foranledning af Löwenmark F.R.I, er der udført numeriske beregninger af Wave Dragons (herefter WD) armes effektivitet for forskellige geometriske udformninger. 5 geometriske modeller, hvor WD's arme er forkortet/forlænget er undersøgt for 3 forskellige drejninger af armene. I alt er 15...
Pappadopulo, Duccio; Trevisan, Gabriele
2016-01-01
A thermally decoupled hidden sector of particles, with a mass gap, generically enters a phase of cannibalism in the early Universe. The Standard Model sector becomes exponentially colder than the hidden sector. We propose the Cannibal Dark Matter framework, where dark matter resides in a cannibalizing sector with a relic density set by 2-to-2 annihilations. Observable signals of Cannibal Dark Matter include a boosted rate for indirect detection, new relativistic degrees of freedom, and warm dark matter.
Del Nobile, Eugenio; Sannino, Francesco
2012-01-01
We organize the effective (self)interaction terms for complex scalar dark matter candidates which are either an isosinglet, isodoublet or an isotriplet with respect to the weak interactions. The classification has been performed ordering the operators in inverse powers of the dark matter cutoff...... scale. We assume Lorentz invariance, color and charge neutrality. We also introduce potentially interesting dark matter induced flavor-changing operators. Our general framework allows for model independent investigations of dark matter properties....
Kopp, Joachim; Liu, Jia; Slatyer, Tracy R.; Wang, Xiao-Ping; Xue, Wei
2016-01-01
We consider a new class of thermal dark matter models, dubbed "Impeded Dark Matter", in which the mass splitting between the dark matter particles and their annihilation products is tiny. Compared to the previously proposed Forbidden Dark Matter scenario, the mass splittings we consider are much smaller, and are allowed to be either positive or negative. We demonstrate that either case can be easily realized without requiring tuning of model parameters. For negative mass splitting, we demonst...
Effective Field Theory of Dark Matter: a Global Analysis
Liem, Sebastian; Calore, Francesca; de Austri, Roberto Ruiz; Tait, Tim M P; Trotta, Roberto; Weniger, Christoph
2016-01-01
We present global fits of an effective field theory description of real, and complex scalar dark matter candidates. We simultaneously take into account all possible dimension 6 operators consisting of dark matter bilinears and gauge invariant combinations of quark and gluon fields. We derive constraints on the free model parameters for both the real (five parameters) and complex (seven) scalar dark matter models obtained by combining Planck data on the cosmic microwave background, direct detection limits from LUX, and indirect detection limits from the Fermi Large Area Telescope. We find that for real scalars indirect dark matter searches disfavour a dark matter particle mass below 100 GeV. For the complex scalar dark matter particle current data have a limited impact due to the presence of operators that lead to p-wave annihilation, and also do not contribute to the spin-independent scattering cross- section. Although current data are not informative enough to strongly constrain the theory parameter space, w...
Physiology and analysis of the electrocardiographic T wave in mice
Speerschneider, T; Thomsen, Morten Bækgaard
2013-01-01
The murine electrocardiogram (ECG) is a valuable tool in cardiac research, although the definition of the T wave has been a matter of debate for several years potentially leading to incomparable data. By this study, we seek to make a clear definition of the murine T wave. Moreover, we investigate...
Wambach, Jochen
2013-01-01
In this presentation I discuss two aspects of the neutron-matter equation of state. One relates to the symmetry energy of nuclear matter and empirical constraints on its slope parameter at saturation density. The second deals with spatially inhomogeneous chiral phases of deconfined quark matter in the inner core of a neutron star.
Frank Peter
2007-11-01
Full Text Available Cet ouvrage collectif, dirigé par Thomas Philipp et Christoph Schumann, réunit 21 contributions portant sur l'émergence de nouvelles identités et idéologies, entre les années 1841 et 1940, dans le Bilâd al-Shâm, la région comprise entre les montagnes du Taurus, le désert syrien, le Sinaï et la Méditerranée. Philipp et Schumann considèrent que peu de recherches ont abordé cette région en tant qu’une unité (as integrated region fondée sur des caractéristiques sociales, culturelles et historiqu...
Gregory Dhen
2010-10-01
Full Text Available Christophe Lazaro s’attaque à un champ encore très peu étudié en sciences sociales, celui d’un objet informatique (un logiciel et de la “communauté” d’individus qui participe à son élaboration et à sa production. Le moins que l’on puisse dire, c’est que le défi est de taille. En effet, sur base de quelles balises méthodologiques et de quelles inspirations épistémologiques se fonder afin d’appréhender ce domaine aussi peu étudié en anthropologie ? Car tel est le paradoxe de la discipline : co...
Russo, Alessandra
2006-01-01
¿Cómo pensar un levantamiento indígena contra la norma colonial sin reducirlo a una de las numerosas “rebeliones” que trataron de sacudir el Reino de la Nueva España a lo largo de su historia? El reto que Christophe Giudicelli asume en su libro Pour une géopolitique de la guerre des Tepehuán (1616-1619) es a la vez taxonómico y metodológico: seguir empleando el término de rebelión impide asumir abiertamente que aquélla de los Tepehuán fue una verdadera guerra. La argumentación ofrecida por el...
Tachyonic approach to neutrino dark matter
Mychelkin, Eduard G
2016-01-01
We apply a new approach based on three relativistic groups (bradyon, tachyon and instanton) forming the `Lorentz groupoid' which allows, in particular, to consider tachyons without introducing imaginary masses and negative energies (related, as known, to violation of causality and unitarity). This leads to effectively scalar conglomerate composed of tachyonic neutrino and antineutrino spinor wave functions as a viable model for stationary dark matter. We also briefly discuss a relevant early non-stationary high-energy stage of the universe evolution.
Fluctuation sound absorption in quark matter
Kerbikov, B O
2016-01-01
We investigate the sound absorption in quark matter due to the interaction of the sound wave with the precritical fluctuations of the diquark-pair field above $T_c$. The soft collective mode of the pair field is derived using the time dependent Ginzburg-Landau functional with random Langevin forces. The strong absorption near the phase transition line may be viewed as a manifestation of the Mandelshtam-Leontovich slow relaxation time theory.
Laser Interferometers as Dark Matter Detectors
Hall, Evan D; Müller, Holger; Pospelov, Maxim; Adhikari, Rana X
2016-01-01
While global cosmological and local galactic abundance of dark matter is well established, its identity, physical size and composition remain a mystery. In this paper, we analyze an important question of dark matter detectability through its gravitational interaction, using current and next generation gravitational-wave observatories to look for macroscopic (kilogram-scale or larger) objects. Keeping the size of the dark matter objects to be smaller than the physical dimensions of the detectors, and keeping their mass as free parameters, we derive the expected event rates. For favorable choice of mass, we find that dark matter interactions could be detected in space-based detectors such as LISA at a rate of one per ten years. We then assume the existence of an additional Yukawa force between dark matter and regular matter. By choosing the range of the force to be comparable to the size of the detectors, we derive the levels of sensitivity to such a new force, which exceeds the sensitivity of other probes in a...
Coupled Cluster studies of infinite nuclear matter
Baardsen, G; Hagen, G; Hjorth-Jensen, M
2013-01-01
The aim of this work is to develop the relevant formalism for performing Coupled Cluster calculations in nuclear matter and neutron star matter, including thereby important correlations to infinite order in the interaction and testing modern nuclear forces based on chiral effective field theory. Our formalism includes the exact treatment of the so-called Pauli operator in a partial wave expansion of the equation of state. Nuclear and neutron matter calculations are done using a coupled particle-particle and hole-hole ladder approximation. The coupled ladder equations are derived as an approximation of CC theory, leaving out particle-hole and non-linear diagrams from the CC doubles amplitude equation. This study is a first step toward CC calculations for nuclear and neutron matter. We present results for both symmetric nuclear matter and pure neutron matter employing state-of-the-art nucleon-nucleon interactions based on chiral effective field theory. We employ also the newly optimized chiral interaction [A. E...
29th International Symposium on Shock Waves
Ranjan, Devesh
2015-01-01
This proceedings present the results of the 29th International Symposium on Shock Waves (ISSW29) which was held in Madison, Wisconsin, U.S.A., from July 14 to July 19, 2013. It was organized by the Wisconsin Shock Tube Laboratory, which is part of the College of Engineering of the University of Wisconsin-Madison. The ISSW29 focused on the following areas: Blast Waves, Chemically Reactive Flows, Detonation and Combustion, Facilities, Flow Visualization, Hypersonic Flow, Ignition, Impact and Compaction, Industrial Applications, Magnetohydrodynamics, Medical and Biological Applications, Nozzle Flow, Numerical Methods, Plasmas, Propulsion, Richtmyer-Meshkov Instability, Shock-Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shock Waves in Condensed Matter, Shock Waves in Multiphase Flow, as well as Shock Waves in Rarefield Flow. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 29 and individuals interes...
Multi-messenger observations of neutron rich matter
Horowitz, C J
2011-01-01
Neutron rich matter is central to many fundamental questions in nuclear physics and astrophysics. Moreover, this material is being studied with an extraordinary variety of new tools such as the Facility for Rare Isotope Beams (FRIB) and the Laser Interferometer Gravitational Wave Observatory (LIGO). We describe the Lead Radius Experiment (PREX) that uses parity violating electron scattering to measure the neutron radius in $^{208}$Pb. This has important implications for neutron stars and their crusts. We discuss X-ray observations of neutron star radii. These also have important implications for neutron rich matter. Gravitational waves (GW) open a new window on neutron rich matter. They come from sources such as neutron star mergers, rotating neutron star mountains, and collective r-mode oscillations. Using large scale molecular dynamics simulations, we find neutron star crust to be very strong. It can support mountains on rotating neutron stars large enough to generate detectable gravitational waves. Finally...
Extracorporeal shock waves as curative therapy for varicose veins?
Fiorenzo Angehrn
2008-03-01
Full Text Available Fiorenzo Angehrn1, Christoph Kuhn1, Ortrud Sonnabend2, Axel Voss31Klinik Piano, Biel, Switzerland; 2Pathodiagnostics, Herisau, Switzerland; 3SwiTech Medical AG, Kreuzlingen, SwitzerlandAbstract: In this prospective design study the effects of low-energy partially focused extracorporeal generated shock waves (ESW onto a subcutaneous located varicose vein – left vena saphena magna (VSM – are investigated. The treatment consisted of 4 ESW applications within 21 days. The varicose VSM of both sides were removed by surgery, and samples analyzed comparing the treated and untreated by means of histopathology. No damage to the treated varicose vein in particular and no mechanical destruction to the varicose vein’s wall could be demonstrated. However, an induction of neo-collagenogenesis was observed. The thickness of the varicose vein’s wall increased. Optimization of critical application parameters by investigating a larger number of patients may turn ESW into a non-invasive curative varicose treatment.Keywords: curative therapy, extra-cellular matrix (ECM, histopathologic changes of varicose veins, extracorporeal shock wave (ESW, progenitor cells
Holographic s-wave and p-wave Josephson junction with backreaction
Wang, Yong-Qiang; Liu, Shuai
2016-11-01
In this paper, we study the holographic models of s-wave and p-wave Josephoson junction away from probe limit in (3+1)-dimensional spacetime, respectively. With the backreaction of the matter, we obtained the anisotropic black hole solution with the condensation of matter fields. We observe that the critical temperature of Josephoson junction decreases with increasing backreaction. In addition to this, the tunneling current and condenstion of Josephoson junction become smaller as backreaction grows larger, but the relationship between current and phase difference still holds for sine function. Moreover, condenstion of Josephoson junction deceases with increasing width of junction exponentially.
Holographic s-wave and p-wave Josephson junction with backreaction
Wang, Yong-Qiang
2016-01-01
In this paper, we study the holographic models of s-wave and p-wave Josephoson junction away from probe limit in (3+1)-dimensional spacetime, respectively. With the backreaction of the matter, we obtained the anisotropic black hole solution with the condensation of matter fields. We observe that the critical temperature of Josephoson junction decreases with increasing backreaction. In addition to this, the tunneling current and condenstion of Josephoson junction become smaller as backreaction grows larger, but the relationship between current and phase difference still holds for sine function. Moreover, condenstion of Josephoson junction deceases with increasing width of junction exponentially.
Perturbations of ultralight vector field dark matter
Cembranos, J. A. R.; Maroto, A. L.; Núñez Jareño, S. J.
2017-02-01
We study the dynamics of cosmological perturbations in models of dark matter based on ultralight coherent vector fields. Very much as for scalar field dark matter, we find two different regimes in the evolution: for modes with {k}^2≪ Hma, we have a particle-like behaviour indistinguishable from cold dark matter, whereas for modes with {k}^2≫ Hma, we get a wave-like behaviour in which the sound speed is non-vanishing and of order c s 2 ≃ k 2/ m 2 a 2. This implies that, also in these models, structure formation could be suppressed on small scales. However, unlike the scalar case, the fact that the background evolution contains a non-vanishing homogeneous vector field implies that, in general, the evolution of the three kinds of perturbations (scalar, vector and tensor) can no longer be decoupled at the linear level. More specifically, in the particle regime, the three types of perturbations are actually decoupled, whereas in the wave regime, the three vector field perturbations generate one scalar-tensor and two vector-tensor perturbations in the metric. Also in the wave regime, we find that a non-vanishing anisotropic stress is present in the perturbed energy-momentum tensor giving rise to a gravitational slip of order ( Φ - Ψ)/ Φ ˜ c s 2 . Moreover in this regime the amplitude of the tensor to scalar ratio of the scalar-tensor modes is also h/ Φ ˜ c s 2 . This implies that small-scale density perturbations are necessarily associated to the presence of gravity waves in this model. We compare their spectrum with the sensitivity of present and future gravity waves detectors.
Zhang, Yunlin; Shi, Kun; Liu, Xiaohan; Zhou, Yongqiang; Qin, Boqiang
2014-01-01
Multiple comprehensive in situ bio-optical investigations were conducted from 2005 to 2010 and covered a large variability of total suspended matter (TSM) in Lake Taihu to calibrate and validate a TSM concentration estimation model based on Medium Resolution Imaging Spectrometer (MERIS) data. The estimation model of the TSM concentration in Lake Taihu was developed using top-of-atmosphere (TOA) radiance of MERIS image data at band 9 in combination with a regional empirical atmospheric correction model, which was strongly correlated with the in situ TSM concentration (r(2) = 0.720, pmean square error (RRMSE) and mean relative error (MRE) were 36.9% and 31.6%, respectively, based on an independent validation dataset that produced reliable estimations of the TSM concentration. The developed algorithm was applied to 50 MERIS images from 2003 to 2011 to obtain a high spatial and temporal heterogeneity of TSM concentrations in Lake Taihu. Seasonally, the highest and lowest TSM concentrations were found in spring and autumn, respectively. Spatially, TSM concentrations were high in the southern part and center of the lake and low in Xukou Bay, East Lake Taihu. The lake topography, including the water depth and distance from the shore, had a significant effect on the TSM spatial distribution. A significant correlation was found between the daily average wind speed and TSM concentration (r(2)= 0.685, p<0.001, and n = 50), suggesting a critical role of wind speed in the TSM variations in Lake Taihu. In addition, a low TSM concentration was linked to the appearance of submerged aquatic vegetation (SAV). Therefore, TSM dynamics were controlled by the lake topography, wind-driven sediment resuspension and SAV distribution.
Solitonic axion condensates modeling dark matter halos
Castañeda Valle, David, E-mail: casvada@gmail.com; Mielke, Eckehard W., E-mail: ekke@xanum.uam.mx
2013-09-15
Instead of fluid type dark matter (DM), axion-like scalar fields with a periodic self-interaction or some truncations of it are analyzed as a model of galaxy halos. It is probed if such cold Bose–Einstein type condensates could provide a viable soliton type interpretation of the DM ‘bullets’ observed by means of gravitational lensing in merging galaxy clusters. We study solitary waves for two self-interacting potentials in the relativistic Klein–Gordon equation, mainly in lower dimensions, and visualize the approximately shape-invariant collisions of two ‘lump’ type solitons. -- Highlights: •An axion model of dark matter is considered. •Collision of axion type solitons are studied in a two dimensional toy model. •Relations to dark matter collisions in galaxy clusters are proposed.
Compressed Baryonic Matter: from Nuclei to Pulsars
Xu, Renxin
2013-01-01
Our world is wonderful because of the negligible baryonic part although unknown dark matter and dark energy dominate the Universe. Those nuclei in the daily life are forbidden to fuse by compression due to the Coulomb repulse, nevertheless, it is usually unexpected in extraterrestrial extreme-environments: the gravity in a core of massive evolved star is so strong that all the other forces (including the Coulomb one) could be neglected. Compressed baryonic matter is then produced after supernova, manifesting itself as pulsar-like stars observed. The study of this compressed baryonic matter can not only be meaningful in fundamental physics (e.g., the elementary color interaction at low-energy scale, testing gravity theories, detecting nano-Hertz background gravitational waves), but has also profound implications in engineering applications (including time standard and navigation), and additionally, is focused by Chinese advanced telescopes, either terrestrial or in space. Historically, in 1930s, L. Landau spec...
THz ultrastrong light-matter coupling
Scalari, Giacomo; Cibella, Sara; Leoni, Roberto; Reichl, Christian; Wegscheider, Werner; Beck, Mattias; Faist, Jérôme
2016-01-01
Cavity photon resonators with ultrastrong light-matter interactions are attracting interest both in semiconductor and superconducting systems displaying the capability to manipulate the cavity quantum electrodynamic ground state with controllable physical properties. Here we review a series of experiments aimed at probing the ultrastrong light-matter coupling regime, where the vacuum Rabi splitting $\\Omega$ is comparable to the bare transition frequency $\\omega$ . We present a new platform where the inter-Landau level transition of a two-dimensional electron gas (2DEG) is strongly coupled to the fundamental mode of deeply subwavelength split-ring resonators operating in the mm-wave range. Record-high values of the normalized light-matter coupling ratio $\\frac{\\Omega}{\\omega}= 0.89$ are reached and the system appears highly scalable far into the microwave range.
Density functional calculations of spin-wave dispersion curves.
Kleinman, Leonard; Niu, Qian
1998-03-01
Extending the density functional method of Kubler et al( J. Kubler et al, J. Phys. F 18, 469 (1983) and J. Phys. Condens. Matter 1, 8155 (1989). ) for calcuating spin density wave ground states (but not making their atomic sphere approximation which requires a constant spin polarization direction in each WS sphere) we dicuss the calculation of frozen spin-wave eigenfunctions and their total energies. From these and the results of Niu's talk, we describe the calculation of spin-wave frequencies.
Impact of Wave Dragon on Wave Climate
Andersen, Thomas Lykke; Tedd, James; Kramer, Morten
This report is an advisory paper for use in determining the wave dragon effects on hydrography, by considering the effect on the wave climate in the region of a wave dragon. This is to be used in the impact assessment for the Wave Dragon pre-commercial demonstrator.......This report is an advisory paper for use in determining the wave dragon effects on hydrography, by considering the effect on the wave climate in the region of a wave dragon. This is to be used in the impact assessment for the Wave Dragon pre-commercial demonstrator....
Relativistic spherical plasma waves
Bulanov, S. S.; Maksimchuk, A.; Schroeder, C. B.; Zhidkov, A. G.; Esarey, E.; Leemans, W. P.
2012-02-01
Tightly focused laser pulses that diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we study theoretically and numerically relativistic spherical wake waves and their properties, including wave breaking.
Holographic superconductivity in the presence of dark matter: basic issues
Rogatko, Marek
2016-01-01
The holographic approach to study strongly coupled superconductors in the presence of dark matter is reviewed. We discuss the influence of dark matter on the superconducting transition temperature of both s-wave and p-wave holographic superconductors. The upper critical field, coherence length, penetration depth of holographic superconductors as well as the metal-insulator transitions have also been analysed. Issues related to the validity of AdS/CFT correspondence for the description of superconductors studied in the laboratory and possible experiments directed towards the detection of dark matter are discussed. In doing so we shall compare our assumptions and assertions with those generally accepted in the elementary particle experiments aimed at the detection of dark matter particles.
Kopp, Joachim; Slatyer, Tracy R; Wang, Xiao-Ping; Xue, Wei
2016-01-01
We consider a new class of thermal dark matter models, dubbed "Impeded Dark Matter", in which the mass splitting between the dark matter particles and their annihilation products is tiny. Compared to the previously proposed Forbidden Dark Matter scenario, the mass splittings we consider are much smaller, and are allowed to be either positive or negative. We demonstrate that either case can be easily realized without requiring tuning of model parameters. For negative mass splitting, we demonstrate that the annihilation cross-section for Impeded Dark Matter depends linearly on the dark matter velocity or may even be kinematically forbidden, making this scenario almost insensitive to constraints from the cosmic microwave background and from observations of dwarf galaxies. Accordingly, it may be possible for Impeded Dark Matter to yield observable signals in clusters or the Galactic center, with no corresponding signal in dwarfs. For positive mass splitting, we show that the annihilation cross-section is suppress...
How dark matter came to matter
de Swart, J. G.; Bertone, G.; van Dongen, J.
2017-03-01
The history of the dark matter problem can be traced back to at least the 1930s, but it was not until the early 1970s that the issue of 'missing matter' was widely recognized as problematic. In the latter period, previously separate issues involving missing mass were brought together in a single anomaly. We argue that reference to a straightforward accumulation of evidence alone is inadequate to comprehend this episode. Rather, the rise of cosmological research, the accompanying renewed interest in the theory of relativity and changes in the manpower division of astronomy in the 1960s are key to understanding how dark matter came to matter. At the same time, this story may also enlighten us on the methodological dimensions of past practices of physics and cosmology.
Ciufolini, I; Moschella, U; Fre, P
2001-01-01
Gravitational waves (GWs) are a hot topic and promise to play a central role in astrophysics, cosmology, and theoretical physics. Technological developments have led us to the brink of their direct observation, which could become a reality in the coming years. The direct observation of GWs will open an entirely new field: GW astronomy. This is expected to bring a revolution in our knowledge of the universe by allowing the observation of previously unseen phenomena, such as the coalescence of compact objects (neutron stars and black holes), the fall of stars into supermassive black holes, stellar core collapses, big-bang relics, and the new and unexpected.With a wide range of contributions by leading scientists in the field, Gravitational Waves covers topics such as the basics of GWs, various advanced topics, GW detectors, astrophysics of GW sources, numerical applications, and several recent theoretical developments. The material is written at a level suitable for postgraduate students entering the field.
Kramer, Morten; Frigaard, Peter; Brorsen, Michael
Nærværende rapport beskriver foreløbige hovedkonklusioner på modelforsøg udført på Aalborg Universitet, Institut for Vand, Jord og Miljøteknik med bølgeenergianlægget Wave Star i perioden 13/9 2004 til 12/11 2004.......Nærværende rapport beskriver foreløbige hovedkonklusioner på modelforsøg udført på Aalborg Universitet, Institut for Vand, Jord og Miljøteknik med bølgeenergianlægget Wave Star i perioden 13/9 2004 til 12/11 2004....
How Dark Matter Came to Matter
de Swart, Jaco; Bertone, Gianfranco; Dongen, Jeroen
2017-01-01
The history of the dark matter problem can be traced back to at least the 1930s, but it was not until the early 1970s that the issue of 'missing matter' was widely recognized as problematic. In the latter period, previously separate issues involving missing mass were brought together in a single anomaly. We argue that reference to a straightforward 'accumulation of evidence' alone is inadequate to comprehend this episode. Rather, the rise of cosmological research, the accompanying renewed int...
Ferrarese, Giorgio
2011-01-01
Lectures: A. Jeffrey: Lectures on nonlinear wave propagation.- Y. Choquet-Bruhat: Ondes asymptotiques.- G. Boillat: Urti.- Seminars: D. Graffi: Sulla teoria dell'ottica non-lineare.- G. Grioli: Sulla propagazione del calore nei mezzi continui.- T. Manacorda: Onde nei solidi con vincoli interni.- T. Ruggeri: "Entropy principle" and main field for a non linear covariant system.- B. Straughan: Singular surfaces in dipolar materials and possible consequences for continuum mechanics
Jiang, Z
2005-01-01
The International Symposium on Shock Waves (ISSW) is a well established series of conferences held every two years in a different location. A unique feature of the ISSW is the emphasis on bridging the gap between physicists and engineers working in fields as different as gas dynamics, fluid mechanics and materials sciences. The main results presented at these meetings constitute valuable proceedings that offer anyone working in this field an authoritative and comprehensive source of reference.
Revisiting Black Holes as Dark Matter
Kohler, Susanna
2017-02-01
Could dark matter be made of intermediate-mass black holes formed in the beginning of the universe? A recent study takes a renewed look at this question.Galactic LurkersThe nature of dark matter has long been questioned, but the recent discovery of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO) has renewed interest in the possibility that dark matter could consist of primordial black holes in the mass range of 101000 solar masses.The relative amounts of the different constituents of the universe. Dark matter makes up roughly 27%. [ESA/Planck]According to this model, the extreme density of matter present during the universes early expansion led to the formation of a large number of intermediate-mass black holes. These black holes now hide in the halos of galaxies, constituting the mass that weve measured dynamically but remains unseen.LIGOs first gravitational-wave detection revealed the merger of two black holes that were both tens of solar masses in size. If primordial black holes are indeed a major constituent of dark matter, then LIGOs detection is consistent with what we would expect to find: occasional mergers of the intermediate-mass black holes that formed in the early universe and now lurk in galactic halos.Quasar MicrolensingTheres a catch, however. If there truly were a large number of intermediate-mass primordial black holes hiding in galactic halos, they wouldnt go completely unnoticed: we would see signs of their presence in the gravitational microlensing of background quasars. Unseen primordial black holes in a foreground galaxy could cause an image of a background quasar to briefly brighten which would provide us with clear evidence of such black holes despite our not being able to detect them directly.A depiction of quasar microlensing (click for a closer look!). The microlensing object in the foreground galaxy could be a star (as depicted), a primordial black hole, or any other compact object. [NASA
Standing Waves in an Elastic Spring: A Systematic Study by Video Analysis
Rodrigues Ventura, Daniel; Simeão de Carvalho, Paulo; Adriano Dias, Marco
2017-01-01
The word "wave" is part of the daily language of every student. However, the physical understanding of the concept demands a high level of abstract thought. In physics, waves are oscillating variations of a physical quantity that involve the transfer of energy from one point to another, without displacement of matter. A wave can be…
An allometric scaling law between gray matter and white matter of cerebral cortex
He Jihuan [College of Science, Donghua University, Shanghai, 1882 Yan' an Xilu Road, Shanghai 200051 (China)] e-mail: jhhe@dhu.edu.cn
2006-02-01
An allometric scaling relationship between cortical white and gray volumes is derived from a general model that describes brain's remarkable efficiency and prodigious communications between brain areas. The model assumes that (1) a cell's metabolic rate depends upon cell's surface; (2) the overall basal metabolic rates of brain areas depend upon their fractal structures; (3) differential brain areas have same basal metabolic rate at slow wave sleep. The obtained allometric exponent scaling white matter to gray matter is 1.2, which is very much close to Zhang and Sejnowski's observation data.
Making Waves: Seismic Waves Activities and Demonstrations
Braile, S. J.; Braile, L. W.
2011-12-01
The nature and propagation of seismic waves are fundamental concepts necessary for understanding the exploration of Earth's interior structure and properties, plate tectonics, earthquakes, and seismic hazards. Investigating seismic waves is also an engaging approach to learning basic principles of the physics of waves and wave propagation. Several effective educational activities and demonstrations are available for teaching about seismic waves, including the stretching of a spring to demonstrate elasticity; slinky wave propagation activities for compressional, shear, Rayleigh and Love waves; the human wave activity to demonstrate P- and S- waves in solids and liquids; waves in water in a simple wave tank; seismic wave computer animations; simple shake table demonstrations of model building responses to seismic waves to illustrate earthquake damage to structures; processing and analysis of seismograms using free and easy to use software; and seismic wave simulation software for viewing wave propagation in a spherical Earth. The use of multiple methods for teaching about seismic waves is useful because it provides reinforcement of the fundamental concepts, is adaptable to variable classroom situations and diverse learning styles, and allows one or more methods to be used for authentic assessment. The methods described here have been used effectively with a broad range of audiences, including K-12 students and teachers, undergraduate students in introductory geosciences courses, and geosciences majors.
Teachers Matter. Yes. Schools Matter. Yes. Districts Matter--Really?
Chenoweth, Karin
2015-01-01
School districts shape the conditions in which schools operate and as such can support or undermine school success and thus student success. All of which is to say that school districts matter. This article looks at the success of two districts whose low-income and minority students beat the odds in academic achievement. Lessons from these…
Quark Matter 2011 (QM11) Quark Matter 2011 (QM11)
2011-12-01
International Advisory Committee Antinori, FedericoPaic, Guy Braun-Munzinger, PeterPajares, Carlos Cifarelli, LuisaPeitzmann, Thomas Erazmus, BarbaraRedlich, Krzysztof Eskola, KariRiccati, Lodovico Gaardhøje, Jens JørgenRoland, Gunther Gale, CharlesRoy, Christelle Gelis, FrancoisSchukraft, Jürgen Giubellino, PaoloSinha, Bikash Greiner, CarstenSrivastava, Dinesh Gyulassy, MiklosStachel, Johanna Harris, JohnSteinberg, Peter Hatsuda, TetsuoStroth, Joachim Heinz, UlrichSugitate, Toru Jacak, BarbaraTserruya, Itzhak Karsch, FrithjofVelkovska, Julia Kharzeev, DimaWang, Enke Kodama, TakeshiWang, Xin, Nian Lévai, PéterWessels, Johannes Manko, VladislavXu, Nu Müller, BerndtZajc, William Ollitrault, Jean-Yves Organizing Committee Arleo, FrancoisDupieux, Pascal Bastid, NicoleFurget, Christophe Bourgeois, Marie-LaureGranier de Cassagnac, Raphael Bregant, MarcoGuernane, Rachid Carminati, FedericoHervet, Carnita Castillo, JavierKuhn, Christian Cheynis, BrigitteOlivier, Nathalie Conesa, DelValle, Zaida Connor, MichelleRenshall, Lucy Crochet, PhilippeSuire, Christophe Delagrange, HuguesTihinen, Ulla Program Committee Schutz, Yves (Chair)Baldisseri, Alberto Wiedemann, Urs (co-Chair)Safarik, Karel Aurenche, Patrick
Geometrical vs wave optics under gravitational waves
Angélil, Raymond
2015-01-01
We present some new derivations of the effect of a plane gravitational wave on a light ray. A simple interpretation of the results is that a gravitational wave causes a phase modulation of electromagnetic waves. We arrive at this picture from two contrasting directions, namely null geodesics and Maxwell's equations, or, geometric and wave optics. Under geometric optics, we express the geodesic equations in Hamiltonian form and solve perturbatively for the effect of gravitational waves. We find that the well-known time-delay formula for light generalizes trivially to massive particles. We also recover, by way of a Hamilton-Jacobi equation, the phase modulation obtained under wave optics. Turning then to wave optics, rather than solving Maxwell's equations directly for the fields, as in most previous approaches, we derive a perturbed wave equation (perturbed by the gravitational wave) for the electromagnetic four-potential. From this wave equation it follows that the four-potential and the electric and magnetic...
Ibarra, Alejandro [Physik-Department T30d, Technische Universität München, James-Franck-Straße, 85748 Garching (Germany)
2015-07-15
Neutrinos could be key particles to unravel the nature of the dark matter of the Universe. On the one hand, sterile neutrinos in minimal extensions of the Standard Model are excellent dark matter candidates, producing potentially observable signals in the form of a line in the X-ray sky. On the other hand, the annihilation or the decay of dark matter particles produces, in many plausible dark matter scenarios, a neutrino flux that could be detected at neutrino telescopes, thus providing non-gravitational evidence for dark matter. More conservatively, the non-observation of a significant excess in the neutrino fluxes with respect to the expected astrophysical backgrounds can be used to constrain dark matter properties, such as the self-annihilation cross section, the scattering cross section with nucleons and the lifetime.
Dror, Jeff Asaf; Kuflik, Eric; Ng, Wee Hao
2016-11-18
We propose a new mechanism for thermal dark matter freeze-out, called codecaying dark matter. Multicomponent dark sectors with degenerate particles and out-of-equilibrium decays can codecay to obtain the observed relic density. The dark matter density is exponentially depleted through the decay of nearly degenerate particles rather than from Boltzmann suppression. The relic abundance is set by the dark matter annihilation cross section, which is predicted to be boosted, and the decay rate of the dark sector particles. The mechanism is viable in a broad range of dark matter parameter space, with a robust prediction of an enhanced indirect detection signal. Finally, we present a simple model that realizes codecaying dark matter.
Shear viscosity of nuclear matter
Magner, A G; Grygoriev, U V; Plujko, V A
2016-01-01
Shear viscosity $\\eta$ is calculated for the nuclear matter described as a system of interacting nucleons with the van der Waals (VDW) equation of state. The Boltzmann-Vlasov kinetic equation is solved in terms of the plane waves of the collective overdamped motion. In the frequent collision regime, the shear viscosity depends on the particle number density $n$ through the mean-field parameter $a$ which describes attractive forces in the VDW equation. In the temperature region $T=15\\div 40$~MeV, a ratio of the shear viscosity to the entropy density $s$ is smaller than 1 at the nucleon number density $n =(0.5\\div 1.5)\\,n^{}_0$, where $n^{}_0=0.16\\,$fm$^{-3}$ is the particle density of equilibrium nuclear matter at zero temperature. A minimum of the $\\eta/s$ ratio takes place somewhere in a vicinity of the critical point of the VDW system. Large values of $\\eta/s\\gg 1$ are however found in both the low density, $n\\ll n^{}_0$, and high density, $n>2n^{}_0$, regions. This makes the ideal hydrodynamic approach ina...
Interaction of Tachyons with Matter
Tomaschitz, R
1999-01-01
A new interaction mechanism of superluminal particles with matter is suggested. Tachyons are described by a real Proca field with negative mass square, coupled to a current of subluminal matter. The potential of a static point source in this field theory is a damped periodic function with 1/r-decay. We treat this potential as a perturbation of the Coulomb potential, and study its effects on cross-sections and energy levels. In the limit of large impact parameter, the periodicity of the potential has a pronounced effect on the classical cross-section, which gets singular at the accumulating extrema of the scattering angle. In this limit we define the cross-section wave mechanically, by semiclassical rainbow scattering. The impact of the tachyon potential on the energy levels of hydrogen and hydrogenic ions is calculated by means of Bohr-Sommerfeld quantization. Estimates for the tachyon mass (3 keV) and the coupling constant of the tachyon potential are derived on the basis of high-precision Lamb shift measure...
Trusted, Jennifer
1999-01-01
As Russell said The word matter is, in philosophy, the name of a problem and our scientific investigations and philosophical inquiries show that it becomes more and more complex and interesting as we study it. This book seeks to show how ideas of matter have developed from Democritus to Heisenberg. The problem of matter may well be insoluble but at least we can begin to appreciate the mystery of what is so often taken to be the mundane 'stuff' of common sense.
Gorbunov, D
2013-01-01
Assuming existence of (very) heavy fourth generation of quarks and antiquarks we argue that antibaryon composed of the three heavy antiquarks can be light, stable and invisible, hence a good candidate for the Dark matter particle. Such opportunity allows to keep the baryon number conservation for the generation of the visible baryon asymmetry. The dark matter particles traveling through the ordinary matter will annihilate with nucleons inducing proton(neutron)-decay-like events with ~5GeV energy release in outcoming particles.
Supplying Dark Energy from Scalar Field Dark Matter
Gogberashvili, Merab; Sakharov, Alexander S.
2017-01-01
We consider the hypothesis that the dark matter consists of ultra-light bosons residing in the state of a Bose-Einstein condensate, which behaves as a single coherent wave rather than as individual particles. In galaxies, spatial distribution of scalar field dark matter can be described by the relativistic Klein-Gordon equation on a background space-time with Schwarzschild metric. In such a setup, the equation of state of scalar field dark matter is found to be changing along with galactocent...
Bergström, L
2005-01-01
As cosmology has entered a phase of precision experiments, the content of the universe has been established to contain interesting and not yet fully understood components, namely dark energy and dark matter. While the cause and exact nature of the dark energy remains mysterious, there is greater hope to connect the dark matter to current models of particle physics. Supersymmetric models provide several excellent candidates for dark matter, with the lightest neutralino the prime example. This and other dark matter candidates are discussed, and prospects for their detection summarized. Some methods of detection are explained, and indications of signals in present data are critically examined.
Doi, Masao
2013-01-01
Soft matter (polymers, colloids, surfactants and liquid crystals) are an important class of materials in modern technology. They also form the basis of many future technologies, for example in medical and environmental applications. Soft matter shows complex behaviour between fluids and solids, and used to be a synonym of complex materials. Due to the developments of the past two decades, soft condensed matter can now be discussed on the same sound physical basis as solid condensedmatter. The purpose of this book is to provide an overview of soft matter for undergraduate and graduate students
Feinstein, Fabrice
2000-01-01
The fact that the mass of the visible stars could not account for the gravitational cohesion of the galaxies was the first sign of non-visible (i.e. dark) matter in the Universe. Since then, many observational evidences tell us that most of the matter is indeed dark. The nature of this dark matter is still unknown. There are good reasons to think that most of it is not composed of normal matter. These lectures will review the experimental methods, which have been developed to unravel this mystery and will compare their results with theoretical predictions.
Loop-induced dark matter direct detection signals from gamma-ray lines
Frandsen, Mads Toudal; Haisch, Ulrich; Kahlhoefer, Felix
2012-01-01
Improved limits as well as tentative claims for dark matter annihilation into gamma-ray lines have been presented recently. We study the direct detection cross section induced from dark matter annihilation into two photons in a model-independent fashion, assuming no additional couplings between...... dark matter and nuclei. We find a striking non-standard recoil spectrum due to different destructively interfering contributions to the dark matter nucleus scattering cross section. While in the case of s-wave annihilation the current sensitivity of direct detection experiments is insufficient...... to compete with indirect detection searches, for p-wave annihilation the constraints from direct searches are comparable. This will allow to test dark matter scenarios with p-wave annihilation that predict a large di-photon annihilation cross section in the next generation of experiments....
2014-10-27
2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE CMS -Wave 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...Program CMS -Wave CMS -Wave is a two-dimensional spectral wind-wave generation and transformation model that employs a forward-marching, finite...difference method to solve the wave action conservation equation. Capabilities of CMS -Wave include wave shoaling, refraction, diffraction, reflection
Gravitomagnetic corrections on gravitational waves
Capozziello, S; Forte, L; Garufi, F; Milano, L
2009-01-01
Gravitational waveforms and production could be considerably affected by gravitomagnetic corrections considered in relativistic theory of orbits. Beside the standard periastron effect of General Relativity, new nutation effects come out when c^{-3} corrections are taken into account. Such corrections emerge as soon as matter-current densities and vector gravitational potentials cannot be discarded into dynamics. We study the gravitational waves emitted through the capture, in the gravitational field of massive binary systems (e.g. a very massive black hole on which a stellar object is inspiralling) via the quadrupole approximation, considering precession and nutation effects. We present a numerical study to obtain the gravitational wave luminosity, the total energy output and the gravitational radiation amplitude. From a crude estimate of the expected number of events towards peculiar targets (e.g. globular clusters) and in particular, the rate of events per year for dense stellar clusters at the Galactic Cen...
Contributions to cosmic reionization from dark matter annihilation and decay
Liu, Hongwan; Slatyer, Tracy R.; Zavala, Jesús
2016-09-01
Dark matter annihilation or decay could have a significant impact on the ionization and thermal history of the universe. In this paper, we study the potential contribution of dark matter annihilation (s -wave- or p -wave-dominated) or decay to cosmic reionization, via the production of electrons, positrons and photons. We map out the possible perturbations to the ionization and thermal histories of the universe due to dark matter processes, over a broad range of velocity-averaged annihilation cross sections/decay lifetimes and dark matter masses. We have employed recent numerical studies of the efficiency with which annihilation/decay products induce heating and ionization in the intergalactic medium, and in this work extended them down to a redshift of 1 +z =4 for two different reionization scenarios. We also improve on earlier studies by using the results of detailed structure formation models of dark matter haloes and subhaloes that are consistent with up-to-date N -body simulations, with estimates on the uncertainties that originate from the smallest scales. We find that for dark matter models that are consistent with experimental constraints, a contribution of more than 10% to the ionization fraction at reionization is disallowed for all annihilation scenarios. Such a contribution is possible only for decays into electron/positron pairs, for light dark matter with mass mχ≲100 MeV , and a decay lifetime τχ˜1 024- 1 025 s .
Rosfort, René
2012-01-01
This article questions the methodological conflation at work in Karen Barad's agential realism. Barad's immense appeal is first explained against the tense background of the nature/culture antagonism in the twentieth century. Then, by using some of the penetrating observations of a seventeen......-century philosopher, Princess Elisabeth of Bohemia, Barad's “ethico-onto-epistem-ology” is examined and subsequently criticized for disregarding the persistence of subjectivity, dissolving the ambivalence of the bodily matter(s), and neglecting the need for concrete individuality in ethics....
Doran, C F; Gates, S J Jr; Hübsch, T; Iga, K M; Landweber, G D
2008-01-01
We introduce a variety of four-dimensional N = 2 matter multiplets which have not previously appeared explicitly in the literature. Using these, we develop a class of supersymmetric actions supplying a context for a systematic exploration of N = 2 matter theories, some of which include Hypermultiplet sectors in novel ways. We construct an N = 2 supersymmetric field theory in which the propagating fields are realized off-shell exclusively as Lorentz scalars and Weyl spinors and which involves a sector with precisely the R-charge assignments characteristic of Hypermultiplets.
Kaivarainen, A
2002-01-01
The short version of new quantum and quantitative Hierarchic theory, general for solids and liquids (Kaivarainen, 1989, 1995, physics/0102086) is presented. Condensed matter is considered as system of 3D standing waves (collective excitations) of different nature: thermal de Broglie waves (waves B), IR photons, related to intermolecular oscilla device is that only small part of 300 parameters, yielding by CAMP system, is possible to get, using separate experimental methods, like IR spectroscopy, sound velocimetry, densitometry and refractometry.
Efficient Wave Energy Amplification with Wave Reflectors
Kramer, Morten Mejlhede; Frigaard, Peter Bak
2002-01-01
Wave Energy Converters (WEC's) extract wave energy from a limited area, often a single point or line even though the wave energy is generally spread out along the wave crest. By the use of wave reflectors (reflecting walls) the wave energy is effectively focused and increased to approximately 130......-140%. In the paper a procedure for calculating the efficiency and optimizing the geometry of wave reflectors are described, this by use of a 3D boundary element method. The calculations are verified by laboratory experiments and a very good agreement is found. The paper gives estimates of possible power benifit...... for different geometries of the wave reflectors and optimal geometrical design parameters are specified. On this basis inventors of WEC's can evaluate whether a specific WEC possible could benefit from wave reflectors....
Ash reduction system using electrically heated particulate matter filter
Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J; He, Yongsheng [Sterling Heights, MI
2011-08-16
A control system for reducing ash comprises a temperature estimator module that estimates a temperature of an electrically heated particulate matter (PM) filter. A temperature and position estimator module estimates a position and temperature of an oxidation wave within the electrically heated PM filter. An ash reduction control module adjusts at least one of exhaust flow, fuel and oxygen levels in the electrically heated PM filter to adjust a position of the oxidation wave within the electrically heated PM filter based on the oxidation wave temperature and position.
Light-matter interaction physics and engineering at the nanoscale
Weiner, John
2013-01-01
This book draws together the essential elements of classical electrodynamics, surface wave physics, plasmonic materials, and circuit theory of electrical engineering to provide insight into the essential physics of nanoscale light-matter interaction and to provide design methodology for practical nanoscale plasmonic devices. A chapter on classical and quantal radiation also highlights the similarities (and differences) between the classical fields of Maxwell's equations and the wave functions of Schrodinger's equation. The aim of this chapter is to provide a semiclassical picture of atomic absorption and emission of radiation, lending credence and physical plausibility to the "rules" of standard wave-mechanical calculations.
Schramm, D.N.
1992-03-01
The cosmological dark matter problem is reviewed. The Big Bang Nucleosynthesis constraints on the baryon density are compared with the densities implied by visible matter, dark halos, dynamics of clusters, gravitational lenses, large-scale velocity flows, and the {Omega} = 1 flatness/inflation argument. It is shown that (1) the majority of baryons are dark; and (2) non-baryonic dark matter is probably required on large scales. It is also noted that halo dark matter could be either baryonic or non-baryonic. Descrimination between ``cold`` and ``hot`` non-baryonic candidates is shown to depend on the assumed ``seeds`` that stimulate structure formation. Gaussian density fluctuations, such as those induced by quantum fluctuations, favor cold dark matter, whereas topological defects such as strings, textures or domain walls may work equally or better with hot dark matter. A possible connection between cold dark matter, globular cluster ages and the Hubble constant is mentioned. Recent large-scale structure measurements, coupled with microwave anisotropy limits, are shown to raise some questions for the previously favored density fluctuation picture. Accelerator and underground limits on dark matter candidates are also reviewed.
Schramm, D.N.
1992-03-01
The cosmological dark matter problem is reviewed. The Big Bang Nucleosynthesis constraints on the baryon density are compared with the densities implied by visible matter, dark halos, dynamics of clusters, gravitational lenses, large-scale velocity flows, and the {Omega} = 1 flatness/inflation argument. It is shown that (1) the majority of baryons are dark; and (2) non-baryonic dark matter is probably required on large scales. It is also noted that halo dark matter could be either baryonic or non-baryonic. Descrimination between cold'' and hot'' non-baryonic candidates is shown to depend on the assumed seeds'' that stimulate structure formation. Gaussian density fluctuations, such as those induced by quantum fluctuations, favor cold dark matter, whereas topological defects such as strings, textures or domain walls may work equally or better with hot dark matter. A possible connection between cold dark matter, globular cluster ages and the Hubble constant is mentioned. Recent large-scale structure measurements, coupled with microwave anisotropy limits, are shown to raise some questions for the previously favored density fluctuation picture. Accelerator and underground limits on dark matter candidates are also reviewed.
Asymptotically Safe Dark Matter
Sannino, Francesco; Shoemaker, Ian M.
2015-01-01
We introduce a new paradigm for dark matter (DM) interactions in which the interaction strength is asymptotically safe. In models of this type, the coupling strength is small at low energies but increases at higher energies, and asymptotically approaches a finite constant value. The resulting...... searches are the primary ways to constrain or discover asymptotically safe dark matter....
Asymptotically Safe Dark Matter
Sannino, Francesco; Shoemaker, Ian M.
2015-01-01
We introduce a new paradigm for dark matter (DM) interactions in which the interaction strength is asymptotically safe. In models of this type, the coupling strength is small at low energies but increases at higher energies, and asymptotically approaches a finite constant value. The resulting...... searches are the primary ways to constrain or discover asymptotically safe dark matter....
Blanchet, Luc
2015-01-01
Massive gravity theories have been developed as viable IR modifications of gravity motivated by dark energy and the problem of the cosmological constant. On the other hand, modified gravity and modified dark matter theories were developed with the aim of solving the problems of standard cold dark matter at galactic scales. Here we propose to adapt the framework of ghost-free massive bigravity theories to reformulate the problem of dark matter at galactic scales. We investigate a promising alternative to dark matter called dipolar dark matter (DDM) in which two different species of dark matter are separately coupled to the two metrics of bigravity and are linked together by an internal vector field. We show that this model successfully reproduces the phenomenology of dark matter at galactic scales (i.e. MOND) as a result of a mechanism of gravitational polarisation. The model is safe in the gravitational sector, but because the two types of dark matter interact through the vector field, a ghostly degree of fre...
Gobato, Ricardo; Fedrigo, Desire Francine Gobato
2015-01-01
Our work is an approach between matter and energy. Using the famous equation E = mc^2, Einstein and the Law of Universal Gravitation of Newton, we estimate that a small amount matter converted into energy is needed to lift, using the gravitational potential energy equation on the surface, a mountain of solid iron or even Mount Everest.
Anderson, Lara B.; Gray, James; Raghuram, Nikhil; Taylor, Washington
2016-04-01
We explore a novel type of transition in certain 6D and 4D quantum field theories, in which the matter content of the theory changes while the gauge group and other parts of the spectrum remain invariant. Such transitions can occur, for example, for SU(6) and SU(7) gauge groups, where matter fields in a three-index antisymmetric representation and the fundamental representation are exchanged in the transition for matter in the two-index antisymmetric representation. These matter transitions are realized by passing through superconformal theories at the transition point. We explore these transitions in dual F-theory and heterotic descriptions, where a number of novel features arise. For example, in the heterotic description the relevant 6D SU(7) theories are described by bundles on K3 surfaces where the geometry of the K3 is constrained in addition to the bundle structure. On the F-theory side, non-standard representations such as the three-index antisymmetric representation of SU( N) require Weierstrass models that cannot be realized from the standard SU( N) Tate form. We also briefly describe some other situations, with groups such as Sp(3), SO(12), and SU(3), where analogous matter transitions can occur between different representations. For SU(3), in particular, we find a matter transition between adjoint matter and matter in the symmetric representation, giving an explicit Weierstrass model for the F-theory description of the symmetric representation that complements another recent analogous construction.
Kroustrup, Jonas
studies approach the paper acknowledges that management and project management technologies does matter, but comes in many shapes, and is performed differently in various socio-technical settings. The field of STS offers a new ground for a participatory and practice oriented approach to the development...... of a new direction in project management research that puts management matter into focus....
Dark Matter Detection in Space
Feng, Jonathan L.
2004-01-01
I review prospects for detecting dark matter in space-based experiments, with an emphasis on recent developments. I propose the ``Martha Stewart criterion'' for identifying dark matter candidates that are particularly worth investigation and focus on three that satisfy it: neutralino dark matter, Kaluza-Klein dark matter, and superWIMP gravitino dark matter.
The Top 10 Matters That Matter
2008-01-01
To review what matters most to the people of China,the country’s official Xinhua News Agency created a list of the 10 greatest changes in 2007.Here are the issues that reflect the pulse of the past year
Baudis, Laura
2015-01-01
One of the major challenges of modern physics is to decipher the nature of dark matter. Astrophysical observations provide ample evidence for the existence of an invisible and dominant mass component in the observable universe, from the scales of galaxies up to the largest cosmological scales. The dark matter could be made of new, yet undiscovered elementary particles, with allowed masses and interaction strengths with normal matter spanning an enormous range. Axions, produced non-thermally in the early universe, and weakly interacting massive particles (WIMPs), which froze out of thermal equilibrium with a relic density matching the observations, represent two well-motivated, generic classes of dark matter candidates. Dark matter axions could be detected by exploiting their predicted coupling to two photons, where the highest sensitivity is reached by experiments using a microwave cavity permeated by a strong magnetic field. WIMPs could be directly observed via scatters off atomic nuclei in underground, ultr...
Incompressibility of strange matter
Sinha, M N; Dey, J; Dey, M; Ray, S; Bhowmick, S; Sinha, Monika; Bagchi, Manjari; Dey, Jishnu; Dey, Mira; Ray, Subharthi; Bhowmick, Siddhartha
2002-01-01
Strange stars calculated from a realistic equation of state (EOS) show compact objects in the mass radius curve, when they are solved for gravitational fields via TOV equation. Many of the observed stars seem to fit in with this kind of compactness irrespective of whether they are X-ray pulsars, bursters or soft $\\gamma$ repeaters or radio pulsars. Calculated incompressibility of this strange matter shows continuity with that of nuclear matter. This is important in the cosmic separation of phase scenario. We compare our calculations of incompressibility with that of a nuclear matter EOS. This EOS has a continuous transition to ud-matter at about five times normal density. From a look at the consequent velocity of sound it is found that the transition to ud-matter seems necessary.
Active Ionospheric Generation of ELF/VLF Waves.
1985-08-15
extensions. 2. NONLINEAR INTERACTION OF TWO HF WAVE PACKETS WITH AN ELF WAVE IN THE LOWER IONOSPHERE We assume first that the two interactins hish... matter , besides its intrinsic scientific merit, has a broad spectrum of applications, ransins from ionospheric and magnetospheric probing to low...initial wave envelopes are rectansular and the decay waves have small amplitudes; specifically, we let 1a 2 1/1aL=O.O1, la 3 l=O.0. Because we have in mind
Perturbations of ultralight vector field dark matter
Cembranos, J A R; Jareño, S J Núñez
2016-01-01
We study the dynamics of cosmological perturbations in models of dark matter based on ultralight coherent vector fields. Very much as for scalar field dark matter, we find two different regimes in the evolution: for modes with $k^2\\ll {\\cal H}ma$, we have a particle-like behaviour indistinguishable from cold dark matter, whereas for modes with $k^2\\gg {\\cal H}ma$, we get a wave-like behaviour in which the sound speed is non-vanishing and of order $c_s^2\\simeq k^2/m^2a^2$. This implies that, also in these models, structure formation could be suppressed on small scales. However, unlike the scalar case, the fact that the background evolution contains a non-vanishing homogeneous vector field implies that, in general, the evolution of the three kinds of perturbations (scalar, vector and tensor) can no longer be decoupled at the linear level. More specifically, in the particle regime, the three types of perturbations are actually decoupled, whereas in the wave regime, the three vector field perturbations generate o...
Dark Matter Balls Help Supernovae to Explode
Froggatt, Colin D
2015-01-01
As a solution to the well-known problem that the shock wave potentially responsible for the explosion of a supernova actually tends to stall, we propose a new energy source arising from our model for dark matter. Our earlier model proposed that dark matter should consist of cm-large white dwarf-like objects kept together by a skin separating two different sorts of vacua. These dark matter balls or pearls will collect in the middle of any star throughout its lifetime. At some stage during the development of a supernova the balls will begin to take in neutrons and then other surrounding material. By passing into a ball nucleons fall through a potential of order 10 MeV, causing a severe production of heat - of order 10 foe for a solar mass of material eaten by the balls. The temperature in the iron core will thereby be raised, splitting up the iron into smaller nuclei. This provides a mechanism for reviving the shock wave when it arrives and making the supernova explosion really occur. The onset of the heating d...
Longitudinal nonlinear wave propagation through soft tissue.
Valdez, M; Balachandran, B
2013-04-01
In this paper, wave propagation through soft tissue is investigated. A primary aim of this investigation is to gain a fundamental understanding of the influence of soft tissue nonlinear material properties on the propagation characteristics of stress waves generated by transient loadings. Here, for computational modeling purposes, the soft tissue is modeled as a nonlinear visco-hyperelastic material, the geometry is assumed to be one-dimensional rod geometry, and uniaxial propagation of longitudinal waves is considered. By using the linearized model, a basic understanding of the characteristics of wave propagation is developed through the dispersion relation and in terms of the propagation speed and attenuation. In addition, it is illustrated as to how the linear system can be used to predict brain tissue material parameters through the use of available experimental ultrasonic attenuation curves. Furthermore, frequency thresholds for wave propagation along internal structures, such as axons in the white matter of the brain, are obtained through the linear analysis. With the nonlinear material model, the authors analyze cases in which one of the ends of the rods is fixed and the other end is subjected to a loading. Two variants of the nonlinear model are analyzed and the associated predictions are compared with the predictions of the corresponding linear model. The numerical results illustrate that one of the imprints of the nonlinearity on the wave propagation phenomenon is the steepening of the wave front, leading to jump-like variations in the stress wave profiles. This phenomenon is a consequence of the dependence of the local wave speed on the local deformation of the material. As per the predictions of the nonlinear material model, compressive waves in the structure travel faster than tensile waves. Furthermore, it is found that wave pulses with large amplitudes and small elapsed times are attenuated over shorter spans. This feature is due to the elevated
Bahcall, Neta A
2015-10-06
Most of the mass in the universe is in the form of dark matter--a new type of nonbaryonic particle not yet detected in the laboratory or in other detection experiments. The evidence for the existence of dark matter through its gravitational impact is clear in astronomical observations--from the early observations of the large motions of galaxies in clusters and the motions of stars and gas in galaxies, to observations of the large-scale structure in the universe, gravitational lensing, and the cosmic microwave background. The extensive data consistently show the dominance of dark matter and quantify its amount and distribution, assuming general relativity is valid. The data inform us that the dark matter is nonbaryonic, is "cold" (i.e., moves nonrelativistically in the early universe), and interacts only weakly with matter other than by gravity. The current Lambda cold dark matter cosmology--a simple (but strange) flat cold dark matter model dominated by a cosmological constant Lambda, with only six basic parameters (including the density of matter and of baryons, the initial mass fluctuations amplitude and its scale dependence, and the age of the universe and of the first stars)--fits remarkably well all the accumulated data. However, what is the dark matter? This is one of the most fundamental open questions in cosmology and particle physics. Its existence requires an extension of our current understanding of particle physics or otherwise point to a modification of gravity on cosmological scales. The exploration and ultimate detection of dark matter are led by experiments for direct and indirect detection of this yet mysterious particle.
The Mystery of Matter, World of the Atom Series.
Pollard, William G.
This booklet is one in the "World of the Atome Series" for junior high school students and their teachers. It describes the fascinating story of the search for the key to the structure of matter. These topics are reviewed: the chemical atom of the 19th century, the planetary atom, the wave atom, inside the elementary particles, and the mystery of…
Higgs particles interacting via a scalar Dark Matter field
Bhattacharya, Yajnavalkya; Darewych, Jurij
2016-07-01
We study a system of two Higgs particles, interacting via a scalar Dark Matter mediating field. The variational method in the Hamiltonian formalism of QFT is used to derive relativistic wave equations for the two-Higgs system, using a truncated Fock-space trial state. Approximate solutions of the two-body equations are used to examine the existence of Higgs bound states.
Smooth sandwich gravitational waves
Podolsky, J
1999-01-01
Gravitational waves which are smooth and contain two asymptotically flat regions are constructed from the homogeneous pp-waves vacuum solution. Motion of free test particles is calculated explicitly and the limit to an impulsive wave is also considered.
Georgi, Howard
1993-01-01
The first complete introduction to waves and wave phenomena by a renowned theorist. Covers damping, forced oscillations and resonance; normal modes; symmetries; traveling waves; signals and Fourier analysis; polarization; diffraction.
Matter Effects on Neutrino Oscillations in Different Supernova Models
Xu, Jing; Hu, Li-Jun; Li, Rui-Cheng; Guo, Xin-Heng; Young, Bing-Lin
2016-04-01
In recent years, with the development of simulations about supernova explosion, we have a better understanding about the density profiles and the shock waves in supernovae than before. There might be a reverse shock wave, another sudden change of density except the forward shock wave, or even no shock wave, emerging in the supernova. Instead of using the expression of the crossing probability at the high resonance, PH, we have studied the matter effects on neutrino oscillations in different supernova models. In detail, we have calculated the survival probability of ve (Ps) and the conversion probability of vx (Pc) in the Schrödinger equation within a simplified two-flavor framework for a certain case, in which the neutrino transfers through the supernova matter from an initial flavor eigenstate located at the core of the supernova. Our calculations was based on the data of density in three different supernova models obtained from simulations. In our work, we do not steepen the density gradient around the border of the shock wave, which differs to what was done in most of the other simulations. It is found that the mass and the density distribution of the supernova do make a difference on the behavior of Ps and Pc. With the results of Ps and Pc, we can estimate the number of ve (and vx) remained in the beam after they go through the matter in the supernova. Supported by National Science Foundation of China under Grant Nos. 11175020 and 11275025
Tensor Modes Damping in Matter and Vacuum Dominated Era
Khodagholizadeh, Jafar; Asgari, Ali A
2016-01-01
The present paper has developed an integro-differential equation to propagate cosmological gravitation waves in matter-dominated era in accounting for the presence of free streaming neutrinos as a traceless transverse tensor part of the anisotropic stress tensor. Its focus is on short and long wavelengths of GWs that enter the horizon in matter-dominated era. Results show that the anisotropic stress reduces the squared amplitude by $ 0.03\\%$ for wavelengths, entering the horizon during matter-dominated phase. This reduction is less for those wavelengths that enter the horizon at $ \\Lambda $ dominated era in flat spacetime. All of the calculations have been done in closed spacetime and the results have been compared with the radiation-dominated case for both flat and closed spacetimes. Finally the paper investigates the effect of closed background on the amplitude of the gravitational waves.
Self-consistent proton crystallization in dense neutron star matter
Kutschera, M. [Institute of Nuclear Physics, Cracow (Poland); Wojcik, W. [Politechnika Krakowska, Cracow (Poland)
1992-11-01
We construct a solid-like variational wave functions for protons localized in dense neutron star matter. The localized protons are centered on the lattice sites and the neutron background is described by periodic Bloch wave functions. The self-consistent periodic structure arises due to a collective mean field. For low proton fraction the periodic potential is weak and the neutron Fermi surface is well approximated by a sphere. With the Skyrme forces we find that the proton solid is of lower energy than a uniform matter for densities above n{sub l} {approx} 4 n{sub 0}, where n{sub 0} = 0.17 fm{sup -3} is the nuclear saturation density. We discuss implications of the proton crystallization for properties of dense matter in neutron stars. (author). 7 refs, 8 figs.
Classical and quantum cosmology with two perfect fluids: stiff matter and radiation
Alvarenga, F G; Freitas, R C; Gonçalves, S V B
2016-01-01
In this work the homogeneous and isotropic Universe of Friedmann-Robertson-Walker is studied in the presence of two fluids: stiff matter and radiation described by the Schutz's formalism. We obtain to the classic case the behaviour of the scale factor of the universe. For the quantum case the wave packets are constructed and the wave function of the universe is found.
Wave Propagation in Modified Gravity
Lindroos, Jan Ø; Mota, David F
2015-01-01
We investigate the propagation of scalar waves induced by matter sources in the context of scalar-tensor theories of gravity which include screening mechanisms for the scalar degree of freedom. The usual approach when studying these theories in the non-linear regime of cosmological perturbations is based on the assumption that scalar waves travel at the speed of light. Within General Relativity such approximation is good and leads to no loss of accuracy in the estimation of observables. We find, however, that mass terms and non-linearities in the equations of motion lead to propagation and dispersion velocities significantly different from the speed of light. As the group velocity is the one associated to the propagation of signals, a reduction of its value has direct impact on the behavior and dynamics of nonlinear structures within modified gravity theories with screening. For instance, the internal dynamics of galaxies and satellites submerged in large dark matter halos could be affected by the fact that t...
Wave diffraction by a cosmic string
Fernández-Núñez, Isabel [Departament de Física Quàntica i Astrofísica, Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona (Spain); Institut de Ciències del Cosmos (ICCUB), Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona (Spain); Bulashenko, Oleg, E-mail: oleg.bulashenko@ub.edu [Departament de Física Quàntica i Astrofísica, Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona (Spain)
2016-08-26
We show that if a cosmic string exists, it may be identified through characteristic diffraction pattern in the energy spectrum of the observed signal. In particular, if the string is on the line of sight, the wave field is shown to fit the Cornu spiral. We suggest a simple procedure, based on Keller's geometrical theory of diffraction, which allows to explain wave effects in conical spacetime of a cosmic string in terms of interference of four characteristic rays. Our results are supposed to be valid for scalar massless waves, including gravitational waves, electromagnetic waves, or even sound in case of condensed matter systems with analogous topological defects. - Highlights: • Gravitational waves could help us to reveal cosmic strings – topological defects of early Universe. • Wave diffraction in conical spacetime of a cosmic string is solved analytically. • The Cornu spiral is shown to appear when the string is on the line of sight. • For a string located within our galaxy, the highest amplification would occur at a frequency range of LIGO detector.
Soberman, R K; Soberman, Robert K.; Dubin, Maurice
2001-01-01
A comet-like, but magnitudes smaller, extremely low albedo interstellar meteoroid population of fragile aggregates with solar type composition, measured in space and terrestrially, is most probably the universal dark matter. Although non-baryonic particles cannot be excluded, only "Big Bang" cosmology predicts an appreciable fraction of such alternate forms. As more counter-physics hypotheses are added to fit observation to the expanding universe assumption, a classical physics alternative proffers dark matter interactive red shifts normally correlated with distance. The cosmic microwave background results from size-independent thermal plateau radiation that emanates from dark matter gravitationally drawn into the Galaxy.
Schumann Marc
2015-01-01
Full Text Available This article gives an overview on the status of experimental searches for dark matter at the end of 2014. The main focus is on direct searches for weakly interacting massive particles (WIMPs using underground-based low-background detectors, especially on the new results published in 2014. WIMPs are excellent dark matter candidates, predicted by many theories beyond the standard model of particle physics, and are expected to interact with the target nuclei either via spin-independent (scalar or spin-dependent (axial-vector couplings. Non-WIMP dark matter candidates, especially axions and axion-like particles are also briefly discussed.
Misra, Prasanta K
2012-01-01
Physics of Condensed Matter is designed for a two-semester graduate course on condensed matter physics for students in physics and materials science. While the book offers fundamental ideas and topic areas of condensed matter physics, it also includes many recent topics of interest on which graduate students may choose to do further research. The text can also be used as a one-semester course for advanced undergraduate majors in physics, materials science, solid state chemistry, and electrical engineering, because it offers a breadth of topics applicable to these majors. The book be
Fong, Richard; Doroshkevich, Andrei G.; Turchaninov, Victor I.
1995-07-01
The theory of the formation of large-scale structure in the universe through the action of gravitational instability imply the existence of substantial amounts of baryonic dark matter, of the order of 50% of the total baryon content in the universe, in the ``voids'' or under-dense regions seen in the large-scale distribution of galaxies. We discuss also the large-scale structure of dark matter expected in voids and the present and future possibilities for the observation of this baryonic dark matter in ``voids.''
Fong, R. [Department of Physics, University of Durham, Durham, DH1 3LE (United Kingdom); Doroshkevich, A.G. [Keldysh Institute of Applied Mathematics, 125047 Moscow (Russian Federation)]|[Teoretical Astrophysics Centrum, Blegsdamsvej 17, Copenhagen DK 2100 (Denmark); Turchaninov, V.I. [Keldysh Institute of Applied Mathematics, 125047 Moscow (Russian Federation)
1995-07-01
The theory of the formation of large-scale structure in the universe through the action of gravitational instability imply the existence of substantial amounts of baryonic dark matter, of the order of 50% of the total baryon content in the universe, in the ``voids`` or under-dense regions seen in the large-scale distribution of galaxies. We discuss also the large-scale structure of dark matter expected in voids and the present and future possibilities for the observation of this baryonic dark matter in ``voids.`` {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.
Resconi, Silvia; The ATLAS collaboration
2016-01-01
Results of Dark Matter searches in mono-X analysis with the ATLAS experiment at the Large Hadron Collider are reported. The data were collected in proton–proton collisions at a centre-of-mass energy of 13 TeV and correspond to an integrated luminosity of 3.2 fb-1. A description of the main characteristics of each analysis and how the main backgrounds are estimated is shown. The observed data are in agreement with the expected Standard Model backgrounds for all analysis described. Exclusion limits are presented for Dark Matter models including pair production of dark matter candidates.
Enabling Forbidden Dark Matter
Cline, James; Liu, Hongwan; Slatyer, Tracy; Xue, Wei
2017-01-01
The thermal relic density of dark matter is conventionally set by two-body annihilations. We point out that in many simple models, $3 \\to 2$ annihilations can play an important role in determining the relic density over a broad range of model parameters. This occurs when the two-body annihilation is kinematically forbidden, but the $3\\to 2$ process is allowed; we call this scenario "Not-Forbidden Dark Matter". We illustrate this mechanism for a vector portal dark matter model, showing that fo...
Schumann, Marc
2015-01-01
This article gives an overview on the status of experimental searches for dark matter at the end of 2014. The main focus is on direct searches for weakly interacting massive particles (WIMPs) using underground-based low-background detectors, especially on the new results published in 2014. WIMPs are excellent dark matter candidates, predicted by many theories beyond the standard model of particle physics, and are expected to interact with the target nuclei either via spin-independent (scalar) or spin-dependent (axial-vector) couplings. Non-WIMP dark matter candidates, especially axions and axion-like particles are also briefly discussed.
New Limits on Thermally annihilating Dark Matter from Neutrino Telescopes
Lopes, José
2016-01-01
We used a consistent and robust solar model to obtain upper limits placed by neutrino telescopes, such as Ice- Cube and Super-Kamiokande, on the Dark Matter-nucleon scattering cross-section, for a general model of Dark Matter with a velocity dependent (p-wave) thermally averaged cross-section. In this picture, the Boltzmann equation for the Dark Matter abundance is numerically solved satisfying the Dark Matter density measured from the Cosmic Microwave Background (CMB). We show that for lower cross-sections and higher masses, the Dark Matter annihilation rate drops sharply, resulting in upper bounds on the scattering cross-section one order of magnitude above those derived from a velocity independent (s-wave) annihilation cross-section. Our results show that upper limits on the scattering cross-section obtained from Dark Matter annihilating in the Sun are sensible to the uncertainty in current standard solar models, fluctuating a maximum of 20 % depending on the annihilation channel.
New Limits on Thermally Annihilating Dark Matter from Neutrino Telescopes
Lopes, J.; Lopes, I.
2016-08-01
We used a consistent and robust solar model to obtain upper limits placed by neutrino telescopes, such as IceCube and Super-Kamiokande, on the dark matter-nucleon scattering cross-section, for a general model of dark matter with a velocity dependent (p-wave) thermally averaged cross-section. In this picture, the Boltzmann equation for the dark matter abundance is numerically solved, satisfying the dark matter density measured from the cosmic microwave background. We show that for lower cross-sections and higher masses, the dark matter annihilation rate drops sharply, resulting in upper bounds on the scattering cross-section that are one order of magnitude above those derived from a velocity independent (s-wave) annihilation cross-section. Our results show that upper limits on the scattering cross-section obtained from dark matter annihilating in the Sun are sensible to the uncertainty in current standard solar models, fluctuating by a maximum of 20% depending on the annihilation channel.
Probing the Internal Composition of Neutron Stars with Gravitational Waves
Chatziioannou, Katerina; Klein, Antoine; Cornish, Neil; Yunes, Nicolas
2015-01-01
Gravitational waves from neutron star binary inspirals contain information about the equation of state of supranuclear matter. In the absence of definitive experimental evidence that determines the correct equation of state, a number of diverse models that give the pressure in a neutron star as function of its density have been proposed. These models differ not only in the approximations and techniques they use to solve the many-body Schr\\"odinger equation, but also in the neutron star composition they assume. We study whether gravitational wave observations of neutron star binaries in quasicircular inspirals will allow us to distinguish between equations of state of differing internal composition, thereby providing important information about the properties of extremely high density matter. We carry out a Bayesian model selection analysis, and find that second generation gravitational wave detectors can heavily constrain equations of state that contain only quark matter, but hybrid stars containing both norm...
Nonlinear Waves in a Cigar-Shaped Bose-Einstein Condensate with Dissipation
YANG Qiu-Ying; YANG Xiao-Xian; ZHANG Gui-Qing; SHI Yu-Ren; ZHANG Ying-Yue; DUAN Wen-Shan; CHEN Tian-Lun
2008-01-01
We discuss the possibIe nonlinear waves of atomic matter waves in a cigar-shaped Bose-Einstein condensate with dissipation. The waves can be described by a KdV-type equation. The KdV-type equation has a solitary wave solution. The amplitude, speed, and width of the wave vary exponentially with time t. The dissipative term of γ plays an important role for the wave amplitude, speed, and width. Comparisons have been given between the analytical solutions and the numerical results. It is shown that both are in good agreement.
Tidal deformability of dark matter clumps
Mendes, Raissa F P
2016-01-01
We analyze the tidal deformability of a clump of dark matter particles, modelled by the collisionless Boltzmann equation. We adopt a wave-mechanical approach to the problem, in which the dynamical equations are approximated by a set of Schr\\"{o}dinger-Poisson equations, within the limit that the effective de Broglie wavelength is comparable to the spatial variation scale of the particle distribution. We argue that such a treatment allows for a smaller number of coupled differential equations and more accessible perturbative analyses, while keeping the description within the dynamical timescale relatively accurate. Moreover, it provides an approximate mapping between perturbed boson star configurations and dynamical dark matter clumps. We present an analysis of the tidal deformability of a minimally-coupled boson star to illustrate this (approximate) correspondence.
Matos, T; Urena-Lopez, L A; Núñez, D
2001-01-01
This work is a review of the last results of research on the Scalar Field Dark Matter model of the Universe at cosmological and at galactic level. We present the complete solution to the scalar field cosmological scenario in which the dark matter is modeled by a scalar field $\\Phi$ with the scalar potential $V(\\Phi)=V_{0}(cosh {(\\lambda \\sqrt{\\kappa_{0}}\\Phi)}-1)$ and the dark energy is modeled by a scalar field $\\Psi$, endowed with the scalar potential $\\tilde{V}(\\Psi)= \\tilde{V_{0}}(\\sinh{(\\alpha \\sqrt{\\kappa_{0}}\\Psi)})^{\\beta}$, which together compose the 95% of the total matter energy in the Universe. The model presents successfully deals with the up to date cosmological observations, and is a good candidate to treat the dark matter problem at the galactic level.
Chung, Daniel J.H.; Riotto, Antonio; Chung, Daniel J. H.; Kolb, Edward W.; Riotto, Antonio
1999-01-01
We show that, contrary to the standard lore, dark matter may be superheavy (many orders of magnitude larger than the weak scale). We show that massive particles may be produced naturally during the transition from the inflationary phase to either a matter-dominated or radiation-dominated phase as a result of the expansion of the background spacetime acting on vacuum quantum fluctuations of the dark matter field. We find that as long as there are stable particles whose mass is of the order of the inflaton mass (presumably around 10^13 GeV), they will be produced in sufficient abundance to give Omega_0=1 quite independently of any details of the non-gravitational interactions of the dark-matter field.
Boiling Primordial Matter: 1968
Hagedorn, Rolf
2016-01-01
This introductory article presents in popular language how the view of the early Universe was evolving through 1968 under the influence of than new and recent insights about the thermodynamic properties of strongly interacting matter (by JR, editor).
Godbole, Rohini M
2010-01-01
In this article I trace the development of the human understanding of the "Heart of Matter" from early concepts of "elements" (or alternatively "Panchmahabhootas") to the current status of "quarks" and "leptons" as the fundamental constituents of matter, interacting together via exchange of the various force carrier particles called "gauge bosons" such as the photon, W/Z-boson etc. I would like to show how our understanding of the fundamental constituents of matter has gone hand in hand with our understanding of the fundamental forces in nature. I will also outline how the knowledge of particle physics at the "micro" scale of less than a Fermi(one millionth of a nanometer), enables us to offer explanations of Cosmological observations at the "macro" scale. Consequently these observations, may in turn, help us address some very fundamental questions of the Physics at the "Heart of the Matter".
王卫明
2011-01-01
matter一词用法灵活,既可以作名词,也可作动词。一、matter作名词,主要有以下三种意思：1.事情;问题。作复数时可意为＂事态,情况＂。例如：It is a matter of importance.这事很重要。How did matters stand？情况怎么样？2.物质。例如：The world is made up of matter.世界是由物质构成的。3.要紧事。例如：It makes no matter whether you come or not.你来不来都无关紧要。
Bignami, Giovanni Fabrizio
2006-01-01
"An experiment in Italy has found tantalizing but puzzling evidence for axions, one if the leading candidates for dark matter. The authors explain how a pair of spinning neutron stars should settle the issue once and for all." (3 pages)
Tom McLeish
2005-09-01
Full Text Available A new volume on soft materials ranges broadly across systems and techniques, experiment, and theory. Despite a lack of coherence, there is much of interest, which conveys the energy within soft-matter science, says
Matter Tracking Information System -
Department of Transportation — The Matter Tracking Information System (MTIS) principle function is to streamline and integrate the workload and work activity generated or addressed by our 300 plus...
Campbell, Peter
2000-01-01
Reviews the booklet "The Study of Matter" produced by the Institute of Physics as part of their Shaping the Future series. This booklet is designed for teachers of chemistry, physics, design and technology, and biology. (Author/CCM)
Full Text Available ... Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products For Consumers Home For Consumers Consumer Updates Expiration Dates Matter ... Should Know CDER FOIA Electronic Reading Room Related Consumer Updates How to Dispose of Unused Medicines Identifying ...
Davoudiasl, Hooman; Hooper, Dan; McDermott, Samuel D
2016-01-22
We describe a general scenario, dubbed "inflatable dark matter," in which the density of dark matter particles can be reduced through a short period of late-time inflation in the early Universe. The overproduction of dark matter that is predicted within many, otherwise, well-motivated models of new physics can be elegantly remedied within this context. Thermal relics that would, otherwise, be disfavored can easily be accommodated within this class of scenarios, including dark matter candidates that are very heavy or very light. Furthermore, the nonthermal abundance of grand unified theory or Planck scale axions can be brought to acceptable levels without invoking anthropic tuning of initial conditions. A period of late-time inflation could have occurred over a wide range of scales from ∼MeV to the weak scale or above, and could have been triggered by physics within a hidden sector, with small but not necessarily negligible couplings to the standard model.
Peplow, Mark
2006-01-01
"Unseen mass looks to be more "tepid" than thought. Astronomers have measured the temperature of dark matter for the first time. The discovery should help particle hunters to identify exactly what this mysterious substance is made of" (1 page)
Chiral magnetic plasmons in anomalous relativistic matter
Gorbar, E V; Shovkovy, I A; Sukhachov, P O
2016-01-01
The chiral plasmon modes of relativistic matter in background magnetic and strain-induced pseudomagnetic fields are studied in detail using the consistent chiral kinetic theory. The results reveal a number of anomalous features of these chiral magnetic and pseudomagnetic plasmons that could be used to identify them in experiment. In a system with nonzero electric (chiral) chemical potential, the background magnetic (pseudomagnetic) fields not only modify the values of the plasmon frequencies in the long wavelength limit, but also affect the qualitative dependence on the wave-vector. Similar modifications can be also induced by the chiral shift parameter in Weyl materials. Interestingly, even in the absence of the chiral shift and external fields, the chiral chemical potential alone leads to a splitting of plasmon energies at linear order in the wave vector.
New prospects and techniques for matter wave interferometry with ions
Schütz, Georg; Pooch, Andreas; Schneeweiss, Philipp; Rauschenbeutel, Arno; Hwang, Ing-Shouh; Stibor, Alexander
2013-01-01
We present new developments and potential applications for the first ion-interferometer realized by Maier et al. [1-4], that verified at the end of the last century biprism interference and diffraction of 3 keV helium ions. The design of the setup is based on a coherent field emission source, an electrostatically charged biprism wire as a beam splitter and a multi-channel plate detector. However, due to deficiencies of the coherent ion source in the setup of Maier et al., the interference signal was low, therefore long integration times had to be accepted. In addition, the production of a significant uncharged particle radiation produced a high background intensity. The rest of the instrument proved to have excellent electron and ion optical properties and a high mechanical and electrical stability. Here we describe in detail the original setup and the major innovations to overcome the deficiencies. We introduce a novel single-atom metal tip [5] as a stable, coherent and monochromatic field emission ion sourc...
Multiple photon-echo rephasing of coherent matter waves
Pan, Ruizhi; Yue, Xuguang; Xu, Xia; Lu, Haichang; Zhou, Xiaoji, E-mail: xjzhou@pku.edu.cn
2015-03-20
We investigate the multiple photon echo processes in a Bose–Einstein condensate (BEC) with inhomogeneous momentum broadening. By applying Bragg pulses with adjusted frequency mismatch to induce multiple rephasing, the BEC satisfies the coherence condition for successive superradiance. The atomic system can be efficiently transferred to a high momentum state step by step and emits multiple photon echo signals. These echo signals as a sequence show increasing widths and descending peaks, reflecting a residual dephasing effect due to kinetic-energy phase discrepancy during the population inversions. Our work may contribute to the coherence maintenance for ultracold atomic gas in the quantum information area and the high-precision measurement of atomic momentum width. - Highlights: • A multipulse protocol to induce multiple photon echo rephasing of a BEC is proposed. • Our method is a new and efficient way to transfer the BEC to high momentum modes. • Our method can extend a BEC's coherence time. • The echo sequence is analyzed to study the residual dephasing effect. • The echo decaying is useful in high-precision measurement of BEC's momentum width.
Cavity Cooling of Nanoparticles: Towards Matter-Wave experiments
Millen, James; Kuhn, Stefan; Arndt, Markus
2016-05-01
Levitated systems are a fascinating addition to the world of optically-controlled mechanical resonators. It is predicted that nanoparticles can be cooled to their c.o.m. ground state via the interaction with an optical cavity. By freeing the oscillator from clamping forces dissipation and decoherence is greatly reduced, leading to the potential to produce long-lived, macroscopically spread, mechanical quantum states, allowing tests of collapse models and any mass limit of quantum physics. Reaching the low pressures required to cavity-cool to the ground state has proved challenging. Our approach is to cavity cool a beam of nanoparticles in high vacuum. We can cool the c.o.m. motion of nanospheres a few hundred nanometers in size. Looking forward, we will utilize novel microcavities to enhance optomechanical cooling, preparing particles in a coherent beam ideally suited to ultra-high mass interferometry at 107 a.m.u.
Quantum jumps induced by matter-wave fluctuations
Torres, J M; Zippilli, S; Morigi, G
2010-01-01
We theoretically study the occurrence of quantum jumps in the resonance fluorescence of a trapped atom. Here, the atom is laser cooled in a configuration of level such that the occurrence of a quantum jump is associated to a change of the vibrational center-of-mass motion by one phonon. The statistics of the occurrence of the dark fluorescence period is studied as a function of the physical parameters and the corresponding features in the spectrum of resonance fluorescence are identified. We discuss the information which can be extracted on the atomic motion from the observation of a quantum jump in the considered setup.
Twin Matter Waves for Interferometry Beyond the Classical Limit
Lücke, Bernd; Scherer, Manuel; Kruse, Jens;
2011-01-01
Interferometers with atomic ensembles constitute an integral part of modern precision metrology. However, these interferometers are fundamentally restricted by the shot noise limit, which can only be overcome by creating quantum entanglement among the atoms. We used spin dynamics in Bose-Einstein...
Dual matter-wave inertial sensors in weightlessness
Barrett, Brynle; Antoni-Micollier, Laura; Chichet, Laure; Battelier, Baptiste; Lévèque, Thomas; Landragin, Arnaud; Bouyer, Philippe
2016-12-01
Quantum technology based on cold-atom interferometers is showing great promise for fields such as inertial sensing and fundamental physics. However, the finite free-fall time of the atoms limits the precision achievable on Earth, while in space interrogation times of many seconds will lead to unprecedented sensitivity. Here we realize simultaneous 87Rb-39K interferometers capable of operating in the weightless environment produced during parabolic flight. Large vibration levels (10-2 g Hz-1/2), variations in acceleration (0-1.8 g) and rotation rates (5° s-1) onboard the aircraft present significant challenges. We demonstrate the capability of our correlated quantum system by measuring the Eötvös parameter with systematic-limited uncertainties of 1.1 × 10-3 and 3.0 × 10-4 during standard- and microgravity, respectively. This constitutes a fundamental test of the equivalence principle using quantum sensors in a free-falling vehicle. Our results are applicable to inertial navigation, and can be extended to the trajectory of a satellite for future space missions.
García Sakai, Victoria; Chen, Sow-Hsin
2012-01-01
Dynamics of Soft Matter: Neutron Applications provides an overview of neutron scattering techniques that measure temporal and spatial correlations simultaneously, at the microscopic and/or mesoscopic scale. These techniques offer answers to new questions arising at the interface of physics, chemistry, and biology. Knowledge of the dynamics at these levels is crucial to understanding the soft matter field, which includes colloids, polymers, membranes, biological macromolecules, foams, emulsions towards biological & biomimetic systems, and phenomena involving wetting, friction, adhesion, or micr
Elastically Decoupling Dark Matter
Kuflik, Eric; Lorier, Nicolas Rey-Le; Tsai, Yu-Dai
2015-01-01
We present a novel dark matter candidate, an Elastically Decoupling Relic (ELDER), which is a cold thermal relic whose present abundance is determined by the cross-section of its elastic scattering on Standard Model particles. The dark matter candidate is predicted to have a mass ranging from a few to a few hundred MeV, and an elastic scattering cross-section with electrons, photons and/or neutrinos in the $10^{-3}-1$ fb range.
Candelas, Philip; Rajesh, G; Candelas, Philip; Perevalov, Eugene; Rajesh, Govindan
1998-01-01
We present an algorithm for obtaining the matter content of effective six-dimensional theories resulting from compactification of F-theory on elliptic Calabi-Yau threefolds which are hypersurfaces in toric varieties. The algorithm allows us to read off the matter content of the theory from the polyhedron describing the Calabi-Yau manifold. This is based on the generalized Green-Schwarz anomaly cancellation condition.
Elastically Decoupling Dark Matter.
Kuflik, Eric; Perelstein, Maxim; Lorier, Nicolas Rey-Le; Tsai, Yu-Dai
2016-06-03
We present a novel dark matter candidate, an elastically decoupling relic, which is a cold thermal relic whose present abundance is determined by the cross section of its elastic scattering on standard model particles. The dark matter candidate is predicted to have a mass ranging from a few to a few hundred MeV, and an elastic scattering cross section with electrons, photons and/or neutrinos in the 10^{-3}-1 fb range.
Alternatives to Dark Matter (?)
Aguirre, Anthony
2003-01-01
It has long been known that Newtonian dynamics applied to the visible matter in galaxies and clusters does not correctly describe the dynamics of those systems. While this is generally taken as evidence for dark matter it is in principle possible that instead Newtonian dynamics (and with it General Relativity) breaks down in these systems. Indeed there have been a number of proposals as to how standard gravitational dynamics might be modified so as to correctly explain galactic dynamics witho...
Interaction of gravitational waves with superconductors
Inan, N.A.; Thompson, J.J. [University of California, Schools of Natural Sciences, Merced, CA (United States); Chiao, R.Y. [University of California, Schools of Natural Sciences and Engineering, Merced, CA (United States)
2017-06-15
Applying the Helmholtz Decomposition theorem to linearized General Relativity leads to a gauge-invariant formulation where the transverse-traceless part of the metric perturbation describes gravitational waves in matter. Gravitational waves incident on a superconductor can be described by a linear London-like constituent equation characterized by a ''gravitational shear modulus'' and a corresponding plasma frequency and penetration depth. Electric-like and magnetic-like gravitational tensor fields are defined in terms of the strain field of a gravitational wave. It is shown that in the DC limit, the magnetic-like tensor field is expelled from the superconductor in a gravitational Meissner-like effect. The Cooper pair density is described by the Ginzburg-Landau theory embedded in curved space-time. The ionic lattice is modeled by quantum harmonic oscillators coupled to gravitational waves and characterized by quasi-energy eigenvalues for the phonon modes. The formulation predicts the possibility of a dynamical Casimir effect since the zero-point energy of the ionic lattice phonons is found to be modulated by the gravitational wave, in a quantum analog of a ''Weber-bar effect.'' Applying periodic thermodynamics and the Debye model in the low-temperature limit leads to a free energy density for the ionic lattice. Lastly, we relate the gravitational strain of space to the strain of matter to show that the response to a gravitational wave is far less for the Cooper pair density than for the ionic lattice. This predicts a charge separation effect in the superconductor as a result of the gravitational wave. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Can cellulite be treated with low-energy extracorporeal shock wave therapy?
Fiorenzo Angehrn
2008-01-01
Full Text Available Fiorenzo Angehrn1, Christoph Kuhn1, Axel Voss21Klinik Piano, Gottstattstrasse 24, Biel, Switzerland; 2SwiTech Medical AG, Kreuzlingen, SwitzerlandAbstract: The present study investigates the effects of low-energy defocused extracorporeal generated shock waves on collagen structure of cellulite afflicted skin. Cellulite measurement using high-resolution ultrasound technology was performed before and after low-energy defocused extracorporeal shock wave therapy (ESWT in 21 female subjects. ESWT was applied onto the skin at the lateral thigh twice a week for a period of six weeks. Results provide evidence that low-energy defocused ESWT caused remodeling of the collagen within the dermis of the tested region. Improving device-parameters and therapy regimes will be essential for future development of a scientific based approach to cellulite treatment.Keywords: cellulite (gynoid lipodystrophy, collagen structure of dermis, collagenometry high-resolution ultrasound of skin, low-energy defocused extracorporeal shock wave therapy (ESWT, septa of subcutaneous connective tissue
Harigaya, Keisuke; Lou, Hou Keong
2016-01-01
Motivated by gauge coupling unification and dark matter, we present an extension to the Standard Model where both are achieved by adding an extra new matter multiplet. Such considerations lead to a Grand Unified Theory with very heavy WIMPzilla dark matter, which has mass greater than ~10^7 GeV and must be produced before reheating ends. Naturally, we refer to this scenario as GUTzilla dark matter. Here we present a minimal GUTzilla model, adding a vector-like quark multiplet to the Standard Model. Proton decay constraints require the new multiplet to be both color and electroweak charged, which prompts us to include a new confining SU(3) gauge group that binds the multiplet into a neutral composite dark matter candidate. Current direct detection constraints are evaded due to the large dark matter mass; meanwhile, next-generation direct detection and proton decay experiments will probe much of the parameter space. The relic abundance is strongly dependent on the dynamics of the hidden confining sector, and we...
Stone J.R.
2013-12-01
Full Text Available The microscopic composition and properties of matter at super-saturation densities have been the subject of intense investigation for decades. The scarcity of experimental and observational data has led to the necessary reliance on theoretical models. There remains great uncertainty in these models which, of necessity, have to go beyond the over-simple assumption that high density matter consists only of nucleons and leptons. Heavy strange baryons, mesons and quark matter in different forms and phases have to be included to fulfil basic requirements of fundamental laws of physics. In this contribution latest developments in construction of the Equation of State (EoS of high-density matter at zero and finite temperature assuming different composition of matter will be discussed. Critical comparison of model EoS with available experimental data from heavy ion collisions and observations on neutron stars, including gravitational mass, radii and cooling patterns and data on X-ray burst sources and low mass X-ray binaries are made. Fundamental differences between the EoS of low-density, high temperature matter, such as is created in heavy ion collisions and of high-density, low temperature compact objects is discussed.
Carr, B.J. [Queen Mary and Westfield Coll., London (United Kingdom). Astronomy Unit]|[Fermi National Accelerator Lab., Batavia, IL (United States). NASA/Fermilab Astrophysics Center
1997-03-01
Dark matter may reside in galactic disks, galactic halos, clusters of galaxies and the background Universe. Cosmological nucleosynthesis arguments suggest that only some fraction of the baryons in the Universe are in visible form, so at least some of the dark matter problems could be baryonic. The dark matter in galactic disks (if real) is almost certainly baryonic and, in this case, it is either in white dwarfs or brown dwarfs. The dark matter in galactic halos could be at least partly baryonic and, in this case, it is likely to be contained in the remnants of a first generation of pregalactic or protogalatic stars. The various constrains on the nature of such remnants suggest that brown dwarfs are the most plausible candidates, although (rather perplexingly) microlensing searches currently favor white dwarfs. The dark matter in clusters or intergalactic space could be baryonic only if one gives up the standard cosmological nucleosynthesis scenario or assumes that the dark objects are primordial black holes which formed before nucleosynthesis. If it is non-baryonic and in the form of cold WIMPs (Weakly Interacting Massive Particles), then such particles should also provide some of the halo dark matter. 89 refs., 1 fig., 2 tabs.
Wind-wave amplification mechanisms: possible models for steep wave events in finite depth
P. Montalvo
2013-11-01
Full Text Available We extend the Miles mechanism of wind-wave generation to finite depth. A β-Miles linear growth rate depending on the depth and wind velocity is derived and allows the study of linear growth rates of surface waves from weak to moderate winds in finite depth h. The evolution of β is plotted, for several values of the dispersion parameter kh with k the wave number. For constant depths we find that no matter what the values of wind velocities are, at small enough wave age the β-Miles linear growth rates are in the known deep-water limit. However winds of moderate intensities prevent the waves from growing beyond a critical wave age, which is also constrained by the water depth and is less than the wave age limit of deep water. Depending on wave age and wind velocity, the Jeffreys and Miles mechanisms are compared to determine which of them dominates. A wind-forced nonlinear Schrödinger equation is derived and the Akhmediev, Peregrine and Kuznetsov–Ma breather solutions for weak wind inputs in finite depth h are obtained.