Spacecraft Tests of General Relativity
Anderson, John D.
1997-01-01
Current spacecraft tests of general relativity depend on coherent radio tracking referred to atomic frequency standards at the ground stations. This paper addresses the possibility of improved tests using essentially the current system, but with the added possibility of a space-borne atomic clock. Outside of the obvious measurement of the gravitational frequency shift of the spacecraft clock, a successor to the suborbital flight of a Scout D rocket in 1976 (GP-A Project), other metric tests would benefit most directly by a possible improved sensitivity for the reduced coherent data. For purposes of illustration, two possible missions are discussed. The first is a highly eccentric Earth orbiter, and the second a solar-conjunction experiment to measure the Shapiro time delay using coherent Doppler data instead of the conventional ranging modulation.
Testing general relativity on accelerators
Directory of Open Access Journals (Sweden)
Tigran Kalaydzhyan
2015-11-01
Full Text Available Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyze experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable – maximal energy of the scattered photons – would experience a significant shift in the ambient gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of resolution and expect our work to be a starting point of further high-precision studies on current and future accelerators, such as PETRA, European XFEL and ILC.
Testing General Relativity with Pulsar Timing
Directory of Open Access Journals (Sweden)
Stairs Ingrid H.
2003-01-01
Full Text Available Pulsars of very different types, including isolated objects and binaries (with short- and long-period orbits, and white-dwarf and neutron-star companions provide the means to test both the predictions of general relativity and the viability of alternate theories of gravity. This article presents an overview of pulsars, then discusses the current status of and future prospects for tests of equivalence-principle violations and strong-field gravitational experiments.
Tests of General Relativity with GW150914.
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2016-06-03
The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 10^{13} km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.
Testing General Relativity with Present and Future Astrophysical Observations
Berti, Emanuele; Cardoso, Vitor; Gualtieri, Leonardo; Pani, Paolo; Sperhake, Ulrich; Stein, Leo C; Wex, Norbert; Yagi, Kent; Baker, Tessa; Burgess, C P; Coelho, Flávio S; Doneva, Daniela; De Felice, Antonio; Ferreira, Pedro G; Freire, Paulo C C; Healy, James; Herdeiro, Carlos; Horbatsch, Michael; Kleihaus, Burkhard; Klein, Antoine; Kokkotas, Kostas; Kunz, Jutta; Laguna, Pablo; Lang, Ryan N; Li, Tjonnie G F; Littenberg, Tyson; Matas, Andrew; Mirshekari, Saeed; Okawa, Hirotada; Radu, Eugen; O'Shaughnessy, Richard; Sathyaprakash, Bangalore S; Broeck, Chris Van Den; Winther, Hans A; Witek, Helvi; Aghili, Mir Emad; Alsing, Justin; Bolen, Brett; Bombelli, Luca; Caudill, Sarah; Chen, Liang; Degollado, Juan Carlos; Fujita, Ryuichi; Gao, Caixia; Gerosa, Davide; Kamali, Saeed; Silva, Hector O; Rosa, João G; Sadeghian, Laleh; Sampaio, Marco; Sotani, Hajime; Zilhao, Miguel
2015-01-01
One century after its formulation, Einstein's general relativity has made remarkable predictions and turned out to be compatible with all experimental tests. Most (if not all) of these tests probe the theory in the weak-field regime, and there are theoretical and experimental reasons to believe that general relativity should be modified when gravitational fields are strong and spacetime curvature is large. The best astrophysical laboratories to probe strong-field gravity are black holes and neutron stars, whether isolated or in binary systems. We review the motivations to consider extensions of general relativity. We present a (necessarily incomplete) catalog of modified theories of gravity for which strong-field predictions have been computed and contrasted to Einstein's theory, and we summarize our current understanding of the structure and dynamics of compact objects in these theories. We discuss current bounds on modified gravity from binary pulsar and cosmological observations, and we highlight the poten...
Testing General Relativity Using Gravitational-Wave Observations
Indian Academy of Sciences (India)
Testing General Relativity Using Gravitational-Wave. Observations. Parameswaran Ajith ICTS-TIFR, Bangalore. On behalf of the LIGO Scientific Collaboration and. Virgo Collaboration. 27th Mid-Year Meeting of the Indian Academy of Sciences. 1 July 2016, IISc Bangalore. LIGO-G1601410-v2 indig ...
A superconducting gyroscope to test Einstein's general theory of relativity
Everitt, C. W. F.
1978-01-01
Schiff (1960) proposed a new test of general relativity based on measuring the precessions of the spin axes of gyroscopes in earth orbit. Since 1963 a Stanford research team has been developing an experiment to measure the two effects calculated by Schiff. The gyroscope consists of a uniform sphere of fused quartz 38 mm in diameter, coated with superconductor, electrically suspended and spinning at about 170 Hz in vacuum. The paper describes the proposed flight apparatus and the current state of development of the gyroscope, including techniques for manufacturing and measuring the gyro rotor and housing, generating ultralow magnetic fields, and mechanizing the readout.
Testing general relativity using golden black-hole binaries
Ghosh, Abhirup; Johnson-McDaniel, Nathan K; Mishra, Chandra Kant; Ajith, Parameswaran; Del Pozzo, Walter; Nichols, David A; Chen, Yanbei; Nielsen, Alex B; Berry, Christopher P L; London, Lionel
2016-01-01
The coalescences of stellar-mass black-hole binaries through their inspiral, merger, and ringdown are among the most promising sources for ground-based gravitational-wave (GW) detectors. If a GW signal is observed with sufficient signal-to-noise ratio, the masses and spins of the black holes can be estimated from just the inspiral part of the signal. Using these estimates of the initial parameters of the binary, the mass and spin of the final black hole can be uniquely predicted making use of general-relativistic numerical simulations. In addition, the mass and spin of the final black hole can be independently estimated from the merger-ringdown part of the signal. If the binary black hole dynamics is correctly described by general relativity, these independent estimates have to be consistent with each other. We present a Bayesian implementation of such a test of general relativity, and outline the expected constraints from upcoming GW observations using the second-generation of ground-based GW detectors.
Astrometric tests of General Relativity in the Solar system
Gai, M.; Vecchiato, A.; Riva, A.; Lattanzi, M. G.; Sozzetti, A.; Crosta, M. T.; Busonero, D.
2014-03-01
Micro-arcsec astronomy is able to verify the predictions of theoretical models of gravitation at a level adequate to constraint relevant parameters and select among different formulations. In particular, this concerns the weak field limit applicable to the Sun neighborhood, where competing models can be expressed in a common framework as the Parametrised Post-Newtonian and Parametrised Post-Post-Newtonian formulations. The mission Gaia is going to provide an unprecedented determination of the γ PPN parameter at the 10-6 level. Other recently proposed concepts, as GAME, may improve the precision on γ by one or two orders of magnitude and provide constraints on other crucial phenomenological aspects. We review the key concepts of astrometric tests of General Relativity and discuss a possible development scenario.
Classical tests of General Relativity in thick branes
Dahia, F.; de Albuquerque Silva, Alex
2015-02-01
Classical tests of General Relativity in braneworld scenarios have been investigated recently with the purpose of posing observational constraints on the parameters of some models of infinitely thin brane. Here we consider the motion of test particles in a thick brane scenario that corresponds to a regularized version of the Garriga-Tanaka solution, which describes a black hole solution in RSII model, in the weak field regime. By adapting a mechanism previously formulated in order to describe the confinement of massive tests particles in a domain wall (which simulates classically the trapping of the Dirac field in a domain wall), we study the influence of the brane thickness on the four-dimensional (4D) path of massless particles. Although the geometry is not warped and, therefore, the bound motion in the transverse direction is not decoupled from the movement in the 4D-world, we can find an explicit solution for the light deflection and the time delay, if the motion in the fifth direction is a high frequency oscillation. We verify that, owing to the transverse motion, the light deflection and the time delay depend on the energy of the light rays. This feature may lead to the phenomenon of gravitational rainbow. We also consider the problem from a semi-classical perspective, investigating the effects of the brane thickness on the motion of the zero-mode in the 4D-world.
Testing general relativity with present and future astrophysical observations
Berti, Emanuele; Barausse, Enrico; Cardoso, Vitor; Gualtieri, Leonardo; Pani, Paolo; Sperhake, Ulrich; Stein, Leo C.; Wex, Norbert; Yagi, Kent; Baker, Tessa; Burgess, C. P.; Coelho, Flávio S.; Doneva, Daniela; De Felice, Antonio; Ferreira, Pedro G.; Freire, Paulo C. C.; Healy, James; Herdeiro, Carlos; Horbatsch, Michael; Kleihaus, Burkhard; Klein, Antoine; Kokkotas, Kostas; Kunz, Jutta; Laguna, Pablo; Lang, Ryan N.; Li, Tjonnie G. F.; Littenberg, Tyson; Matas, Andrew; Mirshekari, Saeed; Okawa, Hirotada; Radu, Eugen; O'Shaughnessy, Richard; Sathyaprakash, Bangalore S.; Van Den Broeck, Chris; Winther, Hans A.; Witek, Helvi; Emad Aghili, Mir; Alsing, Justin; Bolen, Brett; Bombelli, Luca; Caudill, Sarah; Chen, Liang; Degollado, Juan Carlos; Fujita, Ryuichi; Gao, Caixia; Gerosa, Davide; Kamali, Saeed; Silva, Hector O.; Rosa, João G.; Sadeghian, Laleh; Sampaio, Marco; Sotani, Hajime; Zilhao, Miguel
2015-12-01
One century after its formulation, Einstein's general relativity (GR) has made remarkable predictions and turned out to be compatible with all experimental tests. Most of these tests probe the theory in the weak-field regime, and there are theoretical and experimental reasons to believe that GR should be modified when gravitational fields are strong and spacetime curvature is large. The best astrophysical laboratories to probe strong-field gravity are black holes and neutron stars, whether isolated or in binary systems. We review the motivations to consider extensions of GR. We present a (necessarily incomplete) catalog of modified theories of gravity for which strong-field predictions have been computed and contrasted to Einstein's theory, and we summarize our current understanding of the structure and dynamics of compact objects in these theories. We discuss current bounds on modified gravity from binary pulsar and cosmological observations, and we highlight the potential of future gravitational wave measurements to inform us on the behavior of gravity in the strong-field regime.
Comparison of Einstein-Boltzmann solvers for testing general relativity
Bellini, E.; Barreira, A.; Frusciante, N.; Hu, B.; Peirone, S.; Raveri, M.; Zumalacárregui, M.; Avilez-Lopez, A.; Ballardini, M.; Battye, R. A.; Bolliet, B.; Calabrese, E.; Dirian, Y.; Ferreira, P. G.; Finelli, F.; Huang, Z.; Ivanov, M. M.; Lesgourgues, J.; Li, B.; Lima, N. A.; Pace, F.; Paoletti, D.; Sawicki, I.; Silvestri, A.; Skordis, C.; Umiltà, C.; Vernizzi, F.
2018-01-01
We compare Einstein-Boltzmann solvers that include modifications to general relativity and find that, for a wide range of models and parameters, they agree to a high level of precision. We look at three general purpose codes that primarily model general scalar-tensor theories, three codes that model Jordan-Brans-Dicke (JBD) gravity, a code that models f (R ) gravity, a code that models covariant Galileons, a code that models Hořava-Lifschitz gravity, and two codes that model nonlocal models of gravity. Comparing predictions of the angular power spectrum of the cosmic microwave background and the power spectrum of dark matter for a suite of different models, we find agreement at the subpercent level. This means that this suite of Einstein-Boltzmann solvers is now sufficiently accurate for precision constraints on cosmological and gravitational parameters.
Testing General Relativity with the Shadow Size of Sgr A(*).
Johannsen, Tim; Broderick, Avery E; Plewa, Philipp M; Chatzopoulos, Sotiris; Doeleman, Sheperd S; Eisenhauer, Frank; Fish, Vincent L; Genzel, Reinhard; Gerhard, Ortwin; Johnson, Michael D
2016-01-22
In general relativity, the angular radius of the shadow of a black hole is primarily determined by its mass-to-distance ratio and depends only weakly on its spin and inclination. If general relativity is violated, however, the shadow size may also depend strongly on parametric deviations from the Kerr metric. Based on a reconstructed image of Sagittarius A^{*} (Sgr A^{*}) from a simulated one-day observing run of a seven-station Event Horizon Telescope (EHT) array, we employ a Markov chain Monte Carlo algorithm to demonstrate that such an observation can measure the angular radius of the shadow of Sgr A^{*} with an uncertainty of ∼1.5 μas (6%). We show that existing mass and distance measurements can be improved significantly when combined with upcoming EHT measurements of the shadow size and that tight constraints on potential deviations from the Kerr metric can be obtained.
Straumann, Norbert
2013-01-01
This book provides a completely revised and expanded version of the previous classic edition ‘General Relativity and Relativistic Astrophysics’. In Part I the foundations of general relativity are thoroughly developed, while Part II is devoted to tests of general relativity and many of its applications. Binary pulsars – our best laboratories for general relativity – are studied in considerable detail. An introduction to gravitational lensing theory is included as well, so as to make the current literature on the subject accessible to readers. Considerable attention is devoted to the study of compact objects, especially to black holes. This includes a detailed derivation of the Kerr solution, Israel’s proof of his uniqueness theorem, and a derivation of the basic laws of black hole physics. Part II ends with Witten’s proof of the positive energy theorem, which is presented in detail, together with the required tools on spin structures and spinor analysis. In Part III, all of the differential geomet...
PLANCK, the Satellite: a New Experimental Test of General Relativity
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Rabounski D.
2008-04-01
Full Text Available If the origin of a microwave background (EMB is the Earth, what would be its density and associated dipole anisotropy measured at different altitudes from the surface of the Earth? The mathematical methods of the General Theory of Relativity are applied herein to answer these questions. The density of the EMB is answered by means of Einstein's equations for the electromagnetic field of the Earth. The dipole anisotropy, which is due to the rapid motion of the source (the Earth in the weak intergalactic field, is analysed by using the geodesic equations for light-like particles (photons, which are mediators for electromagnetic radiation. It is shown that the EMB decreases with altitude so that the density of its energy at the altitude of the COBE orbit (900km is 0.68 times less than that at the altitude of a U2 aeroplane (25km. Furthermore, the density at the 2nd Lagrange point (1.5 million km, the position of the WMAP and PLANCK satellites should be only 10$^{-7}$ of the value detected by a U2 aeroplane or at the COBE orbit. The dipole anisotropy of the EMB doesn't depend on altitude from the surface of the Earth, it should be the same irrespective of the altitude at which measurements are taken. This result is in support to the experimental and observational analysis conducted by P.-M.Robitaille, according to which the 2.7K microwave background, first observed by Penzias and Wilson, is not of cosmic origin, but of the Earth, and is generated by the oceans. WMAP indicated the same anisotropy of the microwave background at the 2nd Lagrange point that near the Earth. Therefore when PLANCK, which is planned on July, 2008, will manifest the 2.7K monopole microwave signal deceased at the 2nd Langrange point, it will be a new experimental verification of Einstein's theory.
PLANCK, the Satellite: a New Experimental Test of General Relativity
Directory of Open Access Journals (Sweden)
Borissova L.
2008-04-01
Full Text Available If the origin of a microwave background (EMB is the Earth, what would be its density and associated dipole anisotropy measured at different altitudes from the surface of the Earth? The mathematical methods of the General Theory of Relativity are applied herein to answer these questions. The density of the EMB is answered by means of Einstein’s equations for the electromagnetic field of the Earth. The dipole anisotropy, which is due to the rapid motion of the source (the Earth in the weak intergalactic field, is analysed by using the geodesic equations for light-like particles (photons, which are mediators for electromagnetic radiation. It is shown that the EMB decreases with altitude so that the density of its energy at the altitude of the COBE orbit (900km is 0.68 times less than that at the altitude of a U2 aeroplane (25 km. Furthermore, the density at the 2nd Lagrange point (1.5 million km, the position of the WMAP and PLANCK satellites should be only 1E-7 of the value detected by a U2 aeroplane or at the COBE orbit. The dipole anisotropy of the EMB doesn’t depend on altitude from the surface of the Earth, it should be the same irrespective of the altitude at which measurements are taken. This result is in support to the experimental and observational analysis conducted by P.-M. Robitaille, according to which the 2.7 K microwave background, first observed by Penzias and Wilson, is not of cosmic origin, but of the Earth, and is generated by the oceans. WMAP indicated the same anisotropy of the microwave background at the 2nd Lagrange point that near the Earth. Therefore when PLANCK, which is planned on July, 2008, will manifest the 2.7 K monopole microwave signal deceased at the 2nd Langrange point, it will be a new experimental verification of Einstein’s theory.
A Test of General Relativity with MESSENGER Mission Data
Genova, A.; Mazarico, E.; Goossens, S. J.; Lemoine, F. G.; Neumann, G. A.; Nicholas, J. B.; Rowlands, D. D.; Smith, D. E.; Zuber, M. T.; Solomon, S. C.
2016-12-01
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft initiated collection of scientific data from the innermost planet during its first flyby of Mercury in January 2008. After two additional Mercury flybys, MESSENGER was inserted into orbit around Mercury on 18 March 2011 and operated for more than four Earth years through 30 April 2015. Data acquired during the flyby and orbital phases have provided crucial information on the formation and evolution of Mercury. The Mercury Laser Altimeter (MLA) and the radio science system, for example, obtained geodetic observations of the topography, gravity field, orientation, and tides of Mercury, which helped constrain its surface and deep interior structure. X-band radio tracking data collected by the NASA Deep Space Network (DSN) allowed the determination of Mercury's gravity field to spherical harmonic degree and order 100, as well as refinement of the planet's obliquity and estimation of the tidal Love number k2. These geophysical parameters are derived from the range-rate observables that measure precisely the motion of the spacecraft in orbit around the planet. However, the DSN stations acquired two other kinds of radio tracking data, range and delta-differential one-way ranging, which also provided precise measurements of Mercury's ephemeris. The proximity of Mercury's orbit to the Sun leads to a significant perihelion precession, which was used by Einstein as confirmation of general relativity (GR) because of its inconsistency with the effects predicted from classical Newtonian theory. MESSENGER data allow the estimation of the GR parameterized post-Newtonian (PPN) coefficients γ and β. Furthermore, determination of Mercury's orbit also allows estimation of the gravitational parameter (GM) and the flattening (J2) of the Sun. We modified our orbit determination software, NASA GSFC's GEODYN II, to enable simultaneous orbit integration of both MESSENGER and the planet Mercury. The
A new golden age: testing general relativity with cosmology.
Bean, Rachel; Ferreira, Pedro G; Taylor, Andy
2011-12-28
Gravity drives the evolution of the Universe and is at the heart of its complexity. Einstein's field equations can be used to work out the detailed dynamics of space and time and to calculate the emergence of large-scale structure in the distribution of galaxies and radiation. Over the past few years, it has become clear that cosmological observations can be used not only to constrain different world models within the context of Einstein gravity but also to constrain the theory of gravity itself. In this article, we look at different aspects of this new field in which cosmology is used to test theories of gravity with a wide range of observations.
A possible new test of general relativity with Juno
Iorio, L
2013-01-01
The expansion in multipoles of the gravitational potential of a rotating body affects the orbital motion of a test particle orbiting it with long-term perturbations both at a classical and at a relativistic level. In this preliminary sensitivity analysis, we show that, for the first time, the J2 c^-2 effects could be measured by the ongoing Juno mission in the gravitational field of Jupiter during its yearlong science phase (10 November 2016-5 October 2017) thanks to its high eccentricity (e=0.947) and to the huge oblateness of Jupiter (J2=1.47 10^-2). The semi-major axis a and the perijove \\omega\\ of Juno are expected to be shifted by \\Delta a =700-900 m and \\Delta\\omega = 50-60 milliarcseconds, respectively, over 1-2 yr. A numerical analysis shows also that the expected J2c^-2 range-rate signal for Juno should be as large as 280 microns per second during a typical 6 h pass at its closest approach. Independent analyses previously performed by other researchers about the measurability of the Lense-Thirring ef...
Canuto, V
2015-01-01
This is an English translation of the Italian version of an encyclopedia chapter that appeared in the Italian Encyclopedia of the Physical Sciences, edited by Bruno Bertotti (1994). Following requests from colleagues we have decided to make it available to a more general readership. We present the motivation for constructing General Relativity, provide a short discussion of tensor algebra, and follow the set up of Einstein equations. We discuss briefly the initial value problem, the linear approximation and how should non gravitational physics be described in curved spacetime.
Khriplovich, I. B
2005-01-01
This book offers an alternative to other textbooks on the subject, providing a more specific discussion of numerous general relativistic effects for readers who have knowledge of classical mechanics and electrodynamics, including special relativity. Coverage includes gravitational lensing, signal retardation in the gravitational field of the Sun, the Reissner-Nordström solution, selected spin effects, the resonance transformation of an electromagnetic wave into a gravitational one, and the entropy and temperature of black holes. The book includes numerous problems at various levels of difficulty, making it ideal also for independent study by a broad readership of advanced students and researchers. I.B. Khriplovich is Chief Researcher, Budker Institute of Nuclear Physics, Novosibirsk, and Chair of Theoretical Physics at Novosibirsk University. Dr. Khriplovich is a Corresponding Member of the Russian Academy of Sciences. He has been awarded the Dirac Medal ``For the advancement of theoretical physics'' by Univ...
Classical tests of general relativity: Brane-world Sun from minimal geometric deformation
Casadio, R.; Ovalle, J.; da Rocha, Roldão
2015-05-01
We consider a solution of the effective four-dimensional brane-world equations, obtained from the general relativistic Schwarzschild metric via the principle of minimal geometric deformation, and investigate the corresponding signatures stemming from the possible existence of a warped extra-dimension. In particular, we derive bounds on an extra-dimensional parameter, closely related with the fundamental gravitational length, from the experimental results of the classical tests of general relativity in the Solar system.
Relative age effects in fitness testing in a general school sample: how relative are they?
Veldhuizen, Scott; Cairney, John; Hay, John; Faught, Brent
2015-01-01
When children or adolescents are grouped by age or year of birth, older individuals tend to outperform younger ones. These phenomena are known as relative age effects (RAEs). RAEs may result directly from differences in maturation, but may also be associated with psychological, pedagogic or other factors. In this article, we attempt to quantify RAEs in a simple fitness task and to identify the mechanisms operating. Data come from a 5-year study of 2278 individuals that included repeated administrations of the 20 m shuttle run. We use mixed-effect modelling to characterise change over time and then examine residuals from these models for evidence of an effect for age relative to peers or for season of birth. Age alone appears to account for RAEs in our sample, with no effects for age relative to peers or month of birth. Age grouping produces large disparities for girls under 12, moderate ones for boys of all ages and negligible ones for girls between 12 and 15. RAEs for this task and population appear to arise from simple age differences. Similar methods may be useful in determining whether other explanations of RAEs are necessary in other contexts. Evaluation processes that take age into account have the potential to mitigate RAEs in general settings.
Barbuto, John E; Moss, Jennifer A
2006-08-01
The relations of intrinsic and extrinsic motivation with use of consultative, legitimating, and pressure influence tactics were examined using validity generalization procedures. 5 to 7 field studies with cumulative samples exceeding 800 were used to test each relationship. Significance was found for relation between agents' intrinsic motivation and their use of consultative influence tactics and agents' extrinsic motivation and their use of legitimating influence tactics.
Classic tests of General Relativity described by brane-based spherically symmetric solutions
Cuzinatto, R R; de Montigny, M; Khanna, F C; da Silva, J M Hoff
2014-01-01
We discuss a way to obtain information about higher dimensions from observations by studying a brane-based spherically symmetric solution. The three classic tests of General Relativity are analyzed in details: the perihelion shift of the planet Mercury, the deflection of light by the Sun, and the gravitational redshift of atomic spectral lines. The braneworld version of these tests exhibits an additional parameter $b$ related to the fifth-coordinate. This constant $b$ can be constrained by comparison with observational data for massive and massless particles.
Classic tests of General Relativity described by brane-based spherically symmetric solutions
Energy Technology Data Exchange (ETDEWEB)
Cuzinatto, R.R. [Universidade Federal de Alfenas, Instituto de Ciencia e Tecnologia, Pocos de Caldas, MG (Brazil); Pompeia, P.J. [Departamento de Ciencia e Tecnologia Aeroespacial, Instituto de Fomento e Coordenacao Industrial, Sao Jose dos Campos, SP (Brazil); Departamento de Ciencia e Tecnologia Aeroespacial, Instituto Tecnologico de Aeronautica, Sao Jose dos Campos, SP (Brazil); De Montigny, M. [University of Alberta, Theoretical Physics Institute, Edmonton, AB (Canada); University of Alberta, Campus Saint-Jean, Edmonton, AB (Canada); Khanna, F.C. [University of Alberta, Theoretical Physics Institute, Edmonton, AB (Canada); TRIUMF, Vancouver, BC (Canada); University of Victoria, Department of Physics and Astronomy, PO box 1700, Victoria, BC (Canada); Silva, J.M.H. da [Universidade Estadual Paulista, Departamento de Fisica e Quimica, Guaratingueta, SP (Brazil)
2014-08-15
We discuss a way to obtain information about higher dimensions from observations by studying a brane-based spherically symmetric solution. The three classic tests of General Relativity are analyzed in detail: the perihelion shift of the planet Mercury, the deflection of light by the Sun, and the gravitational redshift of atomic spectral lines. The braneworld version of these tests exhibits an additional parameter b related to the fifth-coordinate. This constant b can be constrained by comparison with observational data for massive and massless particles. (orig.)
Testing General Relativity with Low-Frequency, Space-Based Gravitational-Wave Detectors.
Gair, Jonathan R; Vallisneri, Michele; Larson, Shane L; Baker, John G
2013-01-01
We review the tests of general relativity that will become possible with space-based gravitational-wave detectors operating in the ∼ 10-5 - 1 Hz low-frequency band. The fundamental aspects of gravitation that can be tested include the presence of additional gravitational fields other than the metric; the number and tensorial nature of gravitational-wave polarization states; the velocity of propagation of gravitational waves; the binding energy and gravitational-wave radiation of binaries, and therefore the time evolution of binary inspirals; the strength and shape of the waves emitted from binary mergers and ringdowns; the true nature of astrophysical black holes; and much more. The strength of this science alone calls for the swift implementation of a space-based detector; the remarkable richness of astrophysics, astronomy, and cosmology in the low-frequency gravitational-wave band make the case even stronger.
Testing General Relativity with Low-Frequency, Space-Based Gravitational-Wave Detectors
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John G. Baker
2013-09-01
Full Text Available We review the tests of general relativity that will become possible with space-based gravitational-wave detectors operating in the ∼ 10^{-5} – 1 Hz low-frequency band. The fundamental aspects of gravitation that can be tested include the presence of additional gravitational fields other than the metric; the number and tensorial nature of gravitational-wave polarization states; the velocity of propagation of gravitational waves; the binding energy and gravitational-wave radiation of binaries, and therefore the time evolution of binary inspirals; the strength and shape of the waves emitted from binary mergers and ringdowns; the true nature of astrophysical black holes; and much more. The strength of this science alone calls for the swift implementation of a space-based detector; the remarkable richness of astrophysics, astronomy, and cosmology in the low-frequency gravitational-wave band make the case even stronger.
Hees, A.; Do, T.; Ghez, A. M.; Martinez, G. D.; Naoz, S.; Becklin, E. E.; Boehle, A.; Chappell, S.; Chu, D.; Dehghanfar, A.; Kosmo, K.; Lu, J. R.; Matthews, K.; Morris, M. R.; Sakai, S.; Schödel, R.; Witzel, G.
2017-05-01
We demonstrate that short-period stars orbiting around the supermassive black hole in our Galactic center can successfully be used to probe the gravitational theory in a strong regime. We use 19 years of observations of the two best measured short-period stars orbiting our Galactic center to constrain a hypothetical fifth force that arises in various scenarios motivated by the development of a unification theory or in some models of dark matter and dark energy. No deviation from general relativity is reported and the fifth force strength is restricted to an upper 95% confidence limit of |α | confidence upper limit on a linear drift of the argument of periastron of the short-period star S0-2 of |ω˙ S0-2| self-consistent test of the gravitational theory using orbital dynamic in a strong gravitational regime, that of a supermassive black hole. A sensitivity analysis for future measurements is also presented.
Gravity Probe B: final results of a space experiment to test general relativity.
Everitt, C W F; DeBra, D B; Parkinson, B W; Turneaure, J P; Conklin, J W; Heifetz, M I; Keiser, G M; Silbergleit, A S; Holmes, T; Kolodziejczak, J; Al-Meshari, M; Mester, J C; Muhlfelder, B; Solomonik, V G; Stahl, K; Worden, P W; Bencze, W; Buchman, S; Clarke, B; Al-Jadaan, A; Al-Jibreen, H; Li, J; Lipa, J A; Lockhart, J M; Al-Suwaidan, B; Taber, M; Wang, S
2011-06-03
Gravity Probe B, launched 20 April 2004, is a space experiment testing two fundamental predictions of Einstein's theory of general relativity (GR), the geodetic and frame-dragging effects, by means of cryogenic gyroscopes in Earth orbit. Data collection started 28 August 2004 and ended 14 August 2005. Analysis of the data from all four gyroscopes results in a geodetic drift rate of -6601.8±18.3 mas/yr and a frame-dragging drift rate of -37.2±7.2 mas/yr, to be compared with the GR predictions of -6606.1 mas/yr and -39.2 mas/yr, respectively ("mas" is milliarcsecond; 1 mas=4.848×10(-9) rad).
Testing General Relativity with the Radio Science Experiment of the BepiColombo mission to Mercury
Schettino, Giulia; Tommei, Giacomo
2016-09-01
The relativity experiment is part of the Mercury Orbiter Radio science Experiment (MORE) on-board the ESA/JAXA BepiColombo mission to Mercury. Thanks to very precise radio tracking from the Earth and accelerometer, it will be possible to perform an accurate test of General Relativity, by constraining a number of post-Newtonian and related parameters with an unprecedented level of accuracy. The Celestial Mechanics Group of the University of Pisa developed a new dedicated software, ORBIT14, to perform the simulations and to determine simultaneously all the parameters of interest within a global least squares fit. After highlighting some critical issues, we report on the results of a full set of simulations, carried out in the most up-to-date mission scenario. For each parameter we discuss the achievable accuracy, in terms of a formal analysis through the covariance matrix and, furthermore, by the introduction of an alternative, more representative, estimation of the errors. We show that, for example, an accuracy of some parts in 10^-6 for the Eddington parameter β and of 10^-5 for the Nordtvedt parameter η can be attained, while accuracies at the level of 5×10^-7 and 1×10^-7 can be achieved for the preferred frames parameters α1 and α2, respectively.
Testing General Relativity with the Radio Science Experiment of the BepiColombo mission to Mercury
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Giulia Schettino
2016-09-01
Full Text Available The relativity experiment is part of the Mercury Orbiter Radio science Experiment (MORE on-board the ESA/JAXA BepiColombo mission to Mercury. Thanks to very precise radio tracking from the Earth and accelerometer, it will be possible to perform an accurate test of General Relativity, by constraining a number of post-Newtonian and related parameters with an unprecedented level of accuracy. The Celestial Mechanics Group of the University of Pisa developed a new dedicated software, ORBIT14, to perform the simulations and to determine simultaneously all the parameters of interest within a global least squares fit. After highlighting some critical issues, we report on the results of a full set of simulations, carried out in the most up-to-date mission scenario. For each parameter we discuss the achievable accuracy, in terms of a formal analysis through the covariance matrix and, furthermore, by the introduction of an alternative, more representative, estimation of the errors. We show that, for example, an accuracy of some parts in 10 − 6 for the Eddington parameter β and of 10 − 5 for the Nordtvedt parameter η can be attained, while accuracies at the level of 5 × 10 − 7 and 1 × 10 − 7 can be achieved for the preferred frames parameters α 1 and α 2 , respectively.
An effective formalism for testing extensions to General Relativity with gravitational waves
Endlich, Solomon; Gorbenko, Victor; Huang, Junwu; Senatore, Leonardo
2017-09-01
The recent direct observation of gravitational waves (GW) from merging black holes opens up the possibility of exploring the theory of gravity in the strong regime at an unprecedented level. It is therefore interesting to explore which extensions to General Relativity (GR) could be detected. We construct an Effective Field Theory (EFT) satisfying the following requirements. It is testable with GW observations; it is consistent with other experiments, including short distance tests of GR; it agrees with widely accepted principles of physics, such as locality, causality and unitarity; and it does not involve new light degrees of freedom. The most general theory satisfying these requirements corresponds to adding to the GR Lagrangian operators constructed out of powers of the Riemann tensor, suppressed by a scale comparable to the curvature of the observed merging binaries. The presence of these operators modifies the gravitational potential between the compact objects, as well as their effective mass and current quadrupoles, ultimately correcting the waveform of the emitted GW.
The Moon as a Laser-ranged Test Body for General Relativity and New Gravitational Physics
Dell'Agnello, Simone; Currie, Douglas
Since the 1970s Lunar Laser Ranging (LLR) to the Apollo/Lunokhod Cube Corner Retroreflector (CCR) Arrays supplied some of the best tests of General Relativity (GR): possible changes in the gravitational constant, gravitational self-energy (PPN parameter beta), weak equivalence principle, geodetic precession, inverse-square force-law. Secondly, LLR has provided significant information on the composition of the deep interior of the Moon. LLR physics analysis also allows to set constraints on extensions of GR (like spacetime torsion) and, possibly, on new gravitational physics which may explain the gravitational universe without Dark Matter and Dark Energy (like, for example, Non-Minimally Coupled gravity, NMC). LLR is the only Apollo/Lunokhod experiment still in operation, since 45 years. In the 1970s Apollo/Lunokohd LLR Arrays contributed a negligible fraction of the ranging error budget. Since the ranging capabilities of ground stations improved by more than two orders of magnitude, now, because of the lunar librations, Apollo/Lunokhod CCR arrays dominate the error budget. With the US/Italy project "LLRRA21/MoonLIGHT (Lunar Laser Ranging Retroreflector Array for the 21st century / Moon Laser Instrumentation for General relativity High accuracy Tests)", University of Maryland and INFN-LNF developed and tested a next-generation LLR payload made by a single, large CCR (100 mm diameter), unaffected by the effect of librations. In fact, we will show that MoonLIGHT reflectors will improve the LLR accuracy by a factor of ten to one hundred in a few years. INFN-LNF also developed a laser retroreflector micropayload to be deployed on the lunar surface to be laser-ranged by lunar orbiters. The latter micropayload will further extend the physics reach of Apollo, Lunokhod and MoonLIGHT CCRs to improve all precision tests of GR and new gravitational physics using LLR data. As an added value for the LRR and SLR (Satellite Laser ranging) disciplines INFN-LNF built and is
Corrigendum to ;Testing general relativity on accelerators; [Phys. Lett. B 750 (2015) 112-116
Kalaydzhyan, Tigran
2017-11-01
I worked on Ref. [1] initially, but disagreement with the author of Ref. [1] on the physical conclusions led to this work. As a result there are textual overlaps with Ref. [1]. The paper differs in many ways from Ref. [1] and, even though some of the mathematical expressions look similar on a superficial level, I obtained opposite conclusions to the ones proposed in Ref. [1]. In particular, Ref. [1] states that the considered experiments contradict general relativity, while I state that they confirm validity of the general relativity within the given experimental precision.
Del Pozzo, Walter; Mandel, Ilya; Vecchio, Alberto
2014-01-01
The second generation of gravitational-wave detectors is scheduled to start operations in 2015. Gravitational-wave signatures of compact binary coalescences could be used to accurately test the strong-field dynamical predictions of general relativity. Computationally expensive data analysis pipelines, including TIGER, have been developed to carry out such tests. As a means to cheaply assess whether a particular deviation from general relativity can be detected, Cornish et al. and Vallisneri recently proposed an approximate scheme to compute the Bayes factor between a general-relativity gravitational-wave model and a model representing a class of alternative theories of gravity parametrised by one additional parameter. This approximate scheme is based on only two easy-to-compute quantities: the signal-to-noise ratio of the signal and the fitting factor between the signal and the manifold of possible waveforms within general relativity. In this work, we compare the prediction from the approximate formula agains...
Experimental Test of the State Estimation-Reversal Tradeoff Relation in General Quantum Measurements
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Geng Chen
2014-06-01
Full Text Available When a measurement has limited strength, only partial information, regarding the initial state, is extracted, and, correspondingly, there is a probability to reverse its effect on the system and retrieve the original state. Recently, a clear and direct quantitative description of this complementary relationship, in terms of a tradeoff relation, was developed by Y. K. Cheong and S. W. Lee. [Phys. Rev. Lett. 109, 150402 (2012]. Here, this tradeoff relation is experimentally verified using polarization-encoded single photons from a quantum dot. Measurement operators representing a complete range, from not affecting the system to a projection to a single polarization state, are realized. In addition, for each measurement operator, an optimal reversal operator is also implemented. The upper bound of the tradeoff relation is mapped to experimental parameters representing the measurement strength. Our results complement the theoretical work and provide a hands-on characterization of general quantum measurements.
Ridgely, Charles T.
2010-01-01
Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced…
Hees, A; Do, T; Ghez, A M; Martinez, G D; Naoz, S; Becklin, E E; Boehle, A; Chappell, S; Chu, D; Dehghanfar, A; Kosmo, K; Lu, J R; Matthews, K; Morris, M R; Sakai, S; Schödel, R; Witzel, G
2017-05-26
We demonstrate that short-period stars orbiting around the supermassive black hole in our Galactic center can successfully be used to probe the gravitational theory in a strong regime. We use 19 years of observations of the two best measured short-period stars orbiting our Galactic center to constrain a hypothetical fifth force that arises in various scenarios motivated by the development of a unification theory or in some models of dark matter and dark energy. No deviation from general relativity is reported and the fifth force strength is restricted to an upper 95% confidence limit of |α|black hole. A sensitivity analysis for future measurements is also presented.
Introduction to general relativity
Parthasarthy, R
2016-01-01
INTRODUCTION TO GENERAL RELATIVITY begins with a description of the geometry of curved space, explaining geodesics, parallel transport, covariant differentiation, geodesic deviation and spacetime symmetry by killing vectors. It then introduces Einstein's theory of gravitation followed by Schwarzschild solution with its relevance to Positive Mass theorem. The three tests for Einstein's gravity are explained. Other exact solutions such as Vaidya, Kerr and Reisner - Nordstrom metric are included. In the Chapter on cosmological solutions, a detailed description of Godel metric is provided. It then introduces five dimensional spacetime of Kaluza showing the unification of gravity with electromagnetism. This is extended to include non-Abelian gauge theory by invoking compact extra dimensions. Explicit expressions in this case for Christoffel connections and ricci tensor are derived and the higher dimensional gravity action is shown to compactification are given.
Directory of Open Access Journals (Sweden)
Crothers S. J.
2005-10-01
Full Text Available Relativistic motion in the gravitational field of a massive body is governed by the external metric of a spherically symmetric extended object. Consequently, any solution for the point-mass is inadequate for the treatment of such motions since it pertains to a fictitious object. I therefore develop herein the physics of the standard tests of General Relativity by means of the generalised solution for the field external to a sphere of incompressible homogeneous fluid.
Ridgely, Charles T.
2010-07-01
Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced by an observer in general coordinates. The general force is then applied to the local co-moving coordinate system of a uniformly accelerating observer, leading to an expression of the inertial force experienced by the observer. Next, applying the general force in Schwarzschild coordinates is shown to lead to familiar expressions of the gravitational force. As a more complex demonstration, the general force is applied to an observer in Boyer-Lindquist coordinates near a rotating, Kerr black hole. It is then shown that when the angular momentum of the black hole goes to zero, the force on the observer reduces to the force on an observer held stationary in Schwarzschild coordinates. As a final consideration, the force on an observer moving in rotating coordinates is derived. Expressing the force in terms of Christoffel symbols in rotating coordinates leads to familiar expressions of the centrifugal and Coriolis forces on the observer. It is envisioned that the techniques presented herein will be most useful to graduate level students, as well as those undergraduate students having experience with general relativity and tensor analysis.
Effects of dark energy perturbations on cosmological tests of general relativity
Dossett, Jason N.; Ishak, Mustapha
2013-11-01
Cosmological tests to distinguish between dark energy (DE) and modifications to gravity are a promising route to obtain clues on the origin of cosmic acceleration. We study here the robustness of these tests to the presence of DE density, velocity, and anisotropic stress perturbations. We find that the dispersion in the growth index parameter remains small enough to distinguish between extreme cases of DE models and some commonly used modified gravity models. The sign of the slope parameter for a redshift-dependent growth index was found to be inconsistent as an additional test in extreme cases of DE models with perturbations. Next, we studied the effect of DE perturbations on the modified growth (MG) parameters that enter the perturbed Einstein equations. We find that while the dark energy perturbations affect the MG parameters, the deviations remain smaller than those due to modified gravity models. Additionally, the deviations due to DE perturbations with a nonzero effective sound speed occur at scale ranges that are completely different than those due to some modified gravity models such as the f(R) models. In the case of modified gravity models with zero anisotropic stress at late times, the simultaneous determination of the effective dark energy equation of state and the MG parameters can provide the distinction between these models and DE. The growth index test was found to be the most robust to these perturbations. The scale dependence of the MG parameters in some cases of modified gravity constitutes a clear-cut discriminant regardless of any DE perturbations. In summary, we find that the currently proposed cosmological tests to distinguish between DE and modified gravity are robust to DE perturbations even for extreme cases. This is certainly the case even for DE models with equations of state of DE that fall well outside of current cosmological constraints.
Lectures on general relativity
Papapetrou, Achille
1974-01-01
This book is an elaboration of lecture notes for the graduate course on General Rela tivity given by the author at Boston University in the spring semester of 1972. It is an introduction to the subject only, as the time available for the course was limited. The author of an introduction to General Relativity is faced from the beginning with the difficult task of choosing which material to include. A general criterion as sisting in this choice is provided by the didactic character of the book: Those chapters have to be included in priority, which will be most useful to the reader in enabling him to understand the methods used in General Relativity, the results obtained so far and possibly the problems still to be solved. This criterion is not sufficient to ensure a unique choice. General Relativity has developed to such a degree, that it is impossible to include in an introductory textbook of a reasonable length even a very condensed treatment of all important problems which have been discussed unt...
Elements of general relativity
Agakov, Vsevolod G.; Zel'Manov, Abram L.
The main principles of general relativity (GR) are expounded, and some of its astronomical applications are discussed. Particular emphasis is placed on mathematical methods of GR developed by Zel'manov, i.e., methods of chronometrically and kinemetrically invariant quantities, and the orthometric form of the monad formalism. The application of Zel'manov's methods to problems of relativistic cosmology are considered, and a semiinverse method for solving the Einstein gravitation equations is developed.
Directory of Open Access Journals (Sweden)
Dragan Branković
2012-09-01
Full Text Available Teaching physical education and physical training of children, should be appropriate to their age abilities and needs. Acquire the diversified movement experience is a priority of physical education in junior school age. Students fourth grade of primary school - age 10-11 years, in the sensitive period for developing coordination and speed capabilities. Sports game handball and mode of the game "mini-handball", which is adapted to students age abilities and spatial characteristics of the majority of primary schools, abundant with various tasks, specifically dominated by natural forms of movement - running, jumping, throwing. Therefore, handball has a significant role in solving the tasks of physical education. The specific motor tests and relations with the general motor skills are particularly important for continuous monitoring of motor development of children. The survey was conducted on 79 boys fourth grade of primary school who participated in the electoral sport of handball in the regular physical education classes. The results of the handball test "ball slalom" and its relation with general motor skills of students fourth grade of primary school, should contribute to the perception of the value of handball as the content of physical education, but also to contribute to the selection and forecast performance of children in handball.
General Relativity and Gravitation
Ashtekar, Abhay; Berger, Beverly; Isenberg, James; MacCallum, Malcolm
2015-07-01
Part I. Einstein's Triumph: 1. 100 years of general relativity George F. R. Ellis; 2. Was Einstein right? Clifford M. Will; 3. Cosmology David Wands, Misao Sasaki, Eiichiro Komatsu, Roy Maartens and Malcolm A. H. MacCallum; 4. Relativistic astrophysics Peter Schneider, Ramesh Narayan, Jeffrey E. McClintock, Peter Mészáros and Martin J. Rees; Part II. New Window on the Universe: 5. Receiving gravitational waves Beverly K. Berger, Karsten Danzmann, Gabriela Gonzalez, Andrea Lommen, Guido Mueller, Albrecht Rüdiger and William Joseph Weber; 6. Sources of gravitational waves. Theory and observations Alessandra Buonanno and B. S. Sathyaprakash; Part III. Gravity is Geometry, After All: 7. Probing strong field gravity through numerical simulations Frans Pretorius, Matthew W. Choptuik and Luis Lehner; 8. The initial value problem of general relativity and its implications Gregory J. Galloway, Pengzi Miao and Richard Schoen; 9. Global behavior of solutions to Einstein's equations Stefanos Aretakis, James Isenberg, Vincent Moncrief and Igor Rodnianski; Part IV. Beyond Einstein: 10. Quantum fields in curved space-times Stefan Hollands and Robert M. Wald; 11. From general relativity to quantum gravity Abhay Ashtekar, Martin Reuter and Carlo Rovelli; 12. Quantum gravity via unification Henriette Elvang and Gary T. Horowitz.
Ghosh, Abhirup; Johnson-McDaniel, Nathan K.; Ghosh, Archisman; Kant Mishra, Chandra; Ajith, Parameswaran; Del Pozzo, Walter; Berry, Christopher P. L.; Nielsen, Alex B.; London, Lionel
2018-01-01
Advanced LIGO’s recent observations of gravitational waves (GWs) from merging binary black holes have opened up a unique laboratory to test general relativity (GR) in the highly relativistic regime. One of the tests used to establish the consistency of the first LIGO event with a binary black hole merger predicted by GR was the inspiral-merger-ringdown consistency test. This involves inferring the mass and spin of the remnant black hole from the inspiral (low-frequency) part of the observed signal and checking for the consistency of the inferred parameters with the same estimated from the post-inspiral (high-frequency) part of the signal. Based on the observed rate of binary black hole mergers, we expect the advanced GW observatories to observe hundreds of binary black hole mergers every year when operating at their design sensitivities, most of them with modest signal to noise ratios (SNRs). Anticipating such observations, this paper shows how constraints from a large number of events with modest SNRs can be combined to produce strong constraints on deviations from GR. Using kludge modified GR waveforms, we demonstrate how this test could identify certain types of deviations from GR if such deviations are present in the signal waveforms. We also study the robustness of this test against reasonable variations of a variety of different analysis parameters.
Coley, Alan A.; Wiltshire, David L.
2017-05-01
General relativity is a set of physical and geometric principles, which lead to a set of (Einstein) field equations that determine the gravitational field and to the geodesic equations that describe light propagation and the motion of particles on the background. But open questions remain, including: what is the scale on which matter and geometry are dynamically coupled in the Einstein equations? Are the field equations valid on small and large scales? What is the largest scale on which matter can be coarse grained while following a geodesic of a solution to Einstein’s equations? We address these questions. If the field equations are causal evolution equations, whose average on cosmological scales is not an exact solution of the Einstein equations, then some simplifying physical principle is required to explain the statistical homogeneity of the late epoch Universe. Such a principle may have its origin in the dynamical coupling between matter and geometry at the quantum level in the early Universe. This possibility is hinted at by diverse approaches to quantum gravity which find a dynamical reduction to two effective dimensions at high energies on one hand, and by cosmological observations which are beginning to strongly restrict the class of viable inflationary phenomenologies on the other. We suggest that the foundational principles of general relativity will play a central role in reformulating the theory of spacetime structure to meet the challenges of cosmology in the 21st century.
Gravitational-Wave Tests of General Relativity with Ground-Based Detectors and Pulsar-Timing Arrays
Directory of Open Access Journals (Sweden)
Nicolás Yunes
2013-11-01
Full Text Available This review is focused on tests of Einstein's theory of general relativity with gravitational waves that are detectable by ground-based interferometers and pulsar-timing experiments. Einstein’s theory has been greatly constrained in the quasi-linear, quasi-stationary regime, where gravity is weak and velocities are small. Gravitational waves will allow us to probe a complimentary, yet previously unexplored regime: the non-linear and dynamical strong-field regime. Such a regime is, for example, applicable to compact binaries coalescing, where characteristic velocities can reach fifty percent the speed of light and gravitational fields are large and dynamical. This review begins with the theoretical basis and the predicted gravitational-wave observables of modified gravity theories. The review continues with a brief description of the detectors, including both gravitational-wave interferometers and pulsar-timing arrays, leading to a discussion of the data analysis formalism that is applicable for such tests. The review ends with a discussion of gravitational-wave tests for compact binary systems.
Gravitational-Wave Tests of General Relativity with Ground-Based Detectors and Pulsar-Timing Arrays.
Yunes, Nicolás; Siemens, Xavier
2013-01-01
This review is focused on tests of Einstein's theory of general relativity with gravitational waves that are detectable by ground-based interferometers and pulsar-timing experiments. Einstein's theory has been greatly constrained in the quasi-linear, quasi-stationary regime, where gravity is weak and velocities are small. Gravitational waves will allow us to probe a complimentary, yet previously unexplored regime: the non-linear and dynamical strong-field regime. Such a regime is, for example, applicable to compact binaries coalescing, where characteristic velocities can reach fifty percent the speed of light and gravitational fields are large and dynamical. This review begins with the theoretical basis and the predicted gravitational-wave observables of modified gravity theories. The review continues with a brief description of the detectors, including both gravitational-wave interferometers and pulsar-timing arrays, leading to a discussion of the data analysis formalism that is applicable for such tests. The review ends with a discussion of gravitational-wave tests for compact binary systems.
Pseudo-complex general relativity
Hess, Peter O; Greiner, Walter
2016-01-01
This volume presents an pseudo-complex extension of General Relativity which addresses these issues and presents proposals for experimental examinations in strong fields near a large mass. General Relativity is a beautiful and well tested theory of gravitation. Nevertheless, it implies conceptual problems like the creation of singularities (Black Holes) as a result of the collapse of large masses, or the appearance of event horizons which exclude parts of the space-time from the observation of external observers. The mathematical and geometrical foundations of this extension are displayed in detail, and applications including orbits and accretion disks around large central masses, neutron stars or cosmological models are introduced. Calculations both for classical and extended applications are often executed in the form of problems with extensive solutions, which makes this volume also a valuable resource for any student of General Relativity.
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Gravitation. [Book on general relativity
Misner, C. W.; Thorne, K. S.; Wheeler, J. A.
1973-01-01
This textbook on gravitation physics (Einstein's general relativity or geometrodynamics) is designed for a rigorous full-year course at the graduate level. The material is presented in two parallel tracks in an attempt to divide key physical ideas from more complex enrichment material to be selected at the discretion of the reader or teacher. The full book is intended to provide competence relative to the laws of physics in flat space-time, Einstein's geometric framework for physics, applications with pulsars and neutron stars, cosmology, the Schwarzschild geometry and gravitational collapse, gravitational waves, experimental tests of Einstein's theory, and mathematical concepts of differential geometry.
General relativity basics and beyond
Date, Ghanashyam
2015-01-01
A Broad Perspective on the Theory of General Relativity and Its Observable Implications General Relativity: Basics and Beyond familiarizes students and beginning researchers with the basic features of the theory of general relativity as well as some of its more advanced aspects. Employing the pedagogical style of a textbook, it includes essential ideas and just enough background material needed for readers to appreciate the issues and current research. Basics The first five chapters form the core of an introductory course on general relativity. The author traces Einstein’s arguments and presents examples of space-times corresponding to different types of gravitational fields. He discusses the adaptation of dynamics in a Riemannian geometry framework, the Einstein equation and its elementary properties, and different phenomena predicted or influenced by general relativity. Beyond Moving on to more sophisticated features of general relativity, the book presents the physical requirements of a well-defined de...
The Confrontation between General Relativity and Experiment
Directory of Open Access Journals (Sweden)
Will Clifford
2001-01-01
Full Text Available The status of experimental tests of general relativity and of theoretical frameworks for analysing them are reviewed. Einstein's equivalence principle (EEP is well supported by experiments such as the Eötvös experiment, tests of special relativity, and the gravitational redshift experiment. Future tests of EEP and of the inverse square law will search for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected in an amount that agrees with general relativity to half a percent using the Hulse-Taylor binary pulsar, and new binary pulsar systems may yield further improvements.When direct observation of gravitational radiation from astrophysical sources begins, new tests of general relativity will be possible.
Generalizations of Heisenberg uncertainty relation
Energy Technology Data Exchange (ETDEWEB)
Trifonov, D.A. [Institute for Nuclear Research, Sofia (Bulgaria)
2002-09-01
A survey on the generalizations of Heisenberg uncertainty relation and a general scheme for their entangled extensions to several states and observables is presented. The scheme is illustrated on the examples of one and two states and canonical quantum observables, and spin and quasi-spin components. Several new uncertainty relations are displayed. (author)
A generalized memory test algorithm
Milner, E. J.
1982-01-01
A general algorithm for testing digital computer memory is presented. The test checks that (1) every bit can be cleared and set in each memory work, and (2) bits are not erroneously cleared and/or set elsewhere in memory at the same time. The algorithm can be applied to any size memory block and any size memory word. It is concise and efficient, requiring the very few cycles through memory. For example, a test of 16-bit-word-size memory requries only 384 cycles through memory. Approximately 15 seconds were required to test a 32K block of such memory, using a microcomputer having a cycle time of 133 nanoseconds.
Directory of Open Access Journals (Sweden)
Bondarescu Ruxandra
2015-01-01
Full Text Available The successful miniaturisation of extremely accurate atomic clocks and atom interferometers invites prospects for satellite missions to perform precision experiments. We discuss the effects predicted by general relativity and alternative theories of gravity that can be detected by a clock, which orbits the Earth. Our experiment relies on the precise tracking of the spacecraft using its observed tick-rate. The spacecraft’s reconstructed four-dimensional trajectory will reveal the nature of gravitational perturbations in Earth’s gravitational field, potentially differentiating between different theories of gravity. This mission can measure multiple relativistic effects all during the course of a single experiment, and constrain the Parametrized Post-Newtonian Parameters around the Earth. A satellite carrying a clock of fractional timing inaccuracy of Δ f / f ∼ 10−16 in an elliptic orbit around the Earth would constrain the PPN parameters |β − 1|, |γ − 1| ≲ 10−6. We also briefly review potential constraints by atom interferometers on scalar tensor theories and in particular on Chameleon and dilaton models.
The Confrontation between General Relativity and Experiment.
Will, Clifford M
2014-01-01
The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed and updated. Einstein's equivalence principle (EEP) is well supported by experiments such as the Eötvös experiment, tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, the Nordtvedt effect in lunar motion, and frame-dragging. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and a growing family of other binary pulsar systems is yielding new tests, especially of strong-field effects. Current and future tests of relativity will center on strong gravity and gravitational waves.
Energy Technology Data Exchange (ETDEWEB)
Ciufolini, Ignazio [Universita del Salento, Dipartimento Ingegneria dell' Innovazione, Lecce (Italy); Sapienza Universita di Roma, Scuola di Ingegneria Aerospaziale, Rome (Italy); Paolozzi, Antonio; Paris, Claudio [Sapienza Universita di Roma, Scuola di Ingegneria Aerospaziale, Rome (Italy); Museo della Fisica e Centro Studi e Ricerche Enrico Fermi, Rome (Italy); Pavlis, Erricos C. [University of Maryland, Joint Center for Earth Systems Technology (JCET), Baltimore County (United States); Koenig, Rolf [GFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam, Potsdam (Germany); Ries, John [University of Texas at Austin, Center for Space Research, Austin (United States); Gurzadyan, Vahe; Khachatryan, Harutyun; Mirzoyan, Sergey [Alikhanian National Laboratory and Yerevan State University, Center for Cosmology and Astrophysics, Yerevan (Armenia); Matzner, Richard [University of Texas at Austin, Theory Center, Austin (United States); Penrose, Roger [University of Oxford, Mathematical Institute, Oxford (United Kingdom); Sindoni, Giampiero [Sapienza Universita di Roma, DIAEE, Rome (Italy)
2016-03-15
We present a test of general relativity, the measurement of the Earth's dragging of inertial frames. Our result is obtained using about 3.5 years of laser-ranged observations of the LARES, LAGEOS, and LAGEOS 2 laser-ranged satellites together with the Earth gravity field model GGM05S produced by the space geodesy mission GRACE. We measure μ = (0.994 ± 0.002) ± 0.05, where μ is the Earth's dragging of inertial frames normalized to its general relativity value, 0.002 is the 1-sigma formal error and 0.05 is our preliminary estimate of systematic error mainly due to the uncertainties in the Earth gravity model GGM05S. Our result is in agreement with the prediction of general relativity. (orig.)
Ciufolini, Ignazio; Paolozzi, Antonio; Pavlis, Erricos C; Koenig, Rolf; Ries, John; Gurzadyan, Vahe; Matzner, Richard; Penrose, Roger; Sindoni, Giampiero; Paris, Claudio; Khachatryan, Harutyun; Mirzoyan, Sergey
2016-01-01
We present a test of general relativity, the measurement of the Earth's dragging of inertial frames. Our result is obtained using about 3.5 years of laser-ranged observations of the LARES, LAGEOS, and LAGEOS 2 laser-ranged satellites together with the Earth gravity field model GGM05S produced by the space geodesy mission GRACE. We measure [Formula: see text], where [Formula: see text] is the Earth's dragging of inertial frames normalized to its general relativity value, 0.002 is the 1-sigma formal error and 0.05 is our preliminary estimate of systematic error mainly due to the uncertainties in the Earth gravity model GGM05S. Our result is in agreement with the prediction of general relativity.
The confrontation between general relativity and experiment
Indian Academy of Sciences (India)
The binary pulsar provides tests of gravitational wave damping and of strong-field general relativity. Future experiments, such as the gravity probe B gyroscope experiment, a satellite test of the equivalence principle, and tests of gravity at short distance to look for extra spatial dimensions could further constrain alternatives to ...
Energy Technology Data Exchange (ETDEWEB)
Pallister, Sam [University of Bristol, School of Mathematics, Bristol (United Kingdom); Coop, Simon [The Barcelona Institute of Science and Technology, ICFO-Institut de Ciencies Fotoniques, Barcelona (Spain); Formichella, Valerio [Politecnico di Torino, Torino (Italy); Istituto Nazionale di Ricerca Metrologica (INRiM), Torino (Italy); Gampierakis, Nicolas [University of East Anglia, School of Natural Sciences, Norwich (United Kingdom); Notaro, Virginia [Sapienza University of Rome, Department of Mechanical and Aerospace Engineering, Rome (Italy); Knott, Paul [University of Sussex, Department of Physics and Astronomy, Brighton (United Kingdom); Azevedo, Rui [Faculdade de Ciencias da Universidade do Porto, Porto (Portugal); Buchheim, Nikolaus [Max Planck Institute of Quantum Optics, Garching (Germany); De Carvalho, Silvio [University of Applied Sciences Wiener Neustadt, Aerospace Engineering Department, Wiener Neustadt (Austria); Jaervelae, Emilia [Aalto University Metsaehovi Radio Observatory, Kylmaelae (Finland); Aalto University Department of Radio Science and Engineering, Aalto (Finland); Laporte, Matthieu [Universite Paris Diderot, APC (AstroParticule et Cosmologie), Paris (France); Kaikkonen, Jukka-Pekka [Aalto University, Low Temperature Laboratory, Department of Applied Physics, Aalto (Finland); Meshksar, Neda [Leibniz University Hanover, Albert Einstein Institute, Hanover (Germany); Nikkanen, Timo [Aalto University Department of Radio Science and Engineering, Aalto (Finland); Finnish Meteorological Institute, Radar and Space Technology Research Group, Helsinki (Finland); Yttergren, Madeleine [Chalmers University of Technology, Physics and Astronomy, Goeteborg (Sweden)
2017-12-15
In this paper we propose an experiment designed to observe a general-relativistic effect on single photon interference. The experiment consists of a folded Mach-Zehnder interferometer, with the arms distributed between a single Earth orbiter and a ground station. By compensating for other degrees of freedom and the motion of the orbiter, this setup aims to detect the influence of general relativistic time dilation on a spatially superposed single photon. The proposal details a payload to measure the required effect, along with an extensive feasibility analysis given current technological capabilities. (orig.)
Testing General Relativity with the Reflection Spectrum of the Supermassive Black Hole in 1H0707-495
Cao, Zheng; Nampalliwar, Sourabh; Bambi, Cosimo; Dauser, Thomas; García, Javier A.
2018-02-01
Recently, we have extended the x-ray reflection model relxill to test the spacetime metric in the strong gravitational field of astrophysical black holes. In the present Letter, we employ this extended model to analyze XMM-Newton, NuSTAR, and Swift data of the supermassive black hole in 1H0707-495 and test deviations from a Kerr metric parametrized by the Johannsen deformation parameter α13. Our results are consistent with the hypothesis that the spacetime metric around the black hole in 1H0707-495 is described by the Kerr solution.
DEFF Research Database (Denmark)
Hietala, M; Hakonen, A; Aro, A R
1995-01-01
In the present study we explore the attitudes of the Finnish population toward genetic testing by conducting a questionnaire study of a stratified sample of the population as well as of family members of patients with a severe hereditary disease, aspartylglucosaminuria (AGU). The questionnaire ev...
General relativity and gravitational waves
Weber, Johanna
1961-01-01
An internationally famous physicist and electrical engineer, the author of this text was a pioneer in the investigation of gravitational waves. Joseph Weber's General Relativity and Gravitational Waves offers a classic treatment of the subject. Appropriate for upper-level undergraduates and graduate students, this text remains ever relevant. Brief but thorough in its introduction to the foundations of general relativity, it also examines the elements of Riemannian geometry and tensor calculus applicable to this field.Approximately a quarter of the contents explores theoretical and experimenta
General relativity 50 years old
1966-01-01
In May 1916, 'The Foundations of General Relativity Theory' by Albert Einstein was published in 'Annalen der Physik'. Fifty years later, this major contribution to scientific thought still has a rather isolated position with respect to the main-stream of scientific theory. (In contrast, the Special Theory of Relativity is one of the cornerstones of sub-nuclear physics.) To mark the anniversary of the publication of Einstein's paper a theoretician from CERN discusses the theory and its present status.
Dimensional Analysis and General Relativity
Lovatt, Ian
2009-01-01
Newton's law of gravitation is a central topic in the first-year physics curriculum. A lecturer can go beyond the physical details and use the history of gravitation to discuss the development of scientific ideas; unfortunately, the most recent chapter in this history, general relativity, is not covered in first-year courses. This paper discusses…
Iafolla, V.; Fiorenza, E.; Lefevre, C.; Lucchesi, D. M.; Morbidini, A.; Nozzoli, S.; Peron, R.; Persichini, M.; Reale, A.; Santoli, F.; Lorenzini, E. C.; Shapiro, I. I.; Ashenberg, J.; Bombardelli, C.; Glashow, S.
This paper reports the development of an experiment (TEPEE/GReAT) to test the Equivalence Principle (EP) at a level of accuracy equal to (5 × 10-15), by means of a differential accelerometer free falling in a cryogenic vacuum capsule released from a stratospheric balloon. Such an accuracy requires resolving a very small signal out of the instrument's intrinsic noise and the noise associated with the instrument's motion. Imperfections in the construction of the detector introduce gravity gradient noise that it is possible to separate from the violation signal spinning the detector around an horizontal axis in order to have the EP violation signal and the gravity gradients one modulated at two different frequencies. Experimental results on prototype instruments showing high sensitivity and common mode rejection factor are shown.
The genesis of general relativity
Norton, John; Renn, Jürgen; Sauer, Tilman; Stachel, John
2007-01-01
This four-volume work represents the most comprehensive documentation and study of the creation of general relativity; one of the fundamental physical theories of the 20th century. It comprises key sources from Einstein and others who from the late 19th to the early 20th century contributed to this monumental development. Some of these sources are presented here in translation for the first time. Einstein’s famous Zurich notebook, which documents the pivotal steps toward general relativity, is reproduced here for the first time and transcribed in its entirety. The volumes offer detailed commentaries and analyses of these sources that are based on a close reading of these documents supplemented by interpretations by the leading historians of relativity. All in all, the facets of this work, based on more than a decade of research, combine to constitute one of the most in-depth studies of a scientific revolution ever written.
Meidam, Jeroen; Tsang, Ka Wa; Goldstein, Janna; Agathos, Michalis; Ghosh, Archisman; Haster, Carl-Johan; Raymond, Vivien; Samajdar, Anuradha; Schmidt, Patricia; Smith, Rory; Blackburn, Kent; Del Pozzo, Walter; Field, Scott E.; Li, Tjonnie; Pürrer, Michael; Van Den Broeck, Chris; Veitch, John; Vitale, Salvatore
2018-02-01
Thanks to the recent discoveries of gravitational wave signals from binary black hole mergers by Advanced Laser Interferometer Gravitational Wave Observatory and Advanced Virgo, the genuinely strong-field dynamics of spacetime can now be probed, allowing for stringent tests of general relativity (GR). One set of tests consists of allowing for parametrized deformations away from GR in the template waveform models and then constraining the size of the deviations, as was done for the detected signals in previous work. In this paper, we construct reduced-order quadratures so as to speed up likelihood calculations for parameter estimation on future events. Next, we explicitly demonstrate the robustness of the parametrized tests by showing that they will correctly indicate consistency with GR if the theory is valid. We also check to what extent deviations from GR can be constrained as information from an increasing number of detections is combined. Finally, we evaluate the sensitivity of the method to possible violations of GR.
Conformal Methods in General Relativity
Valiente Kroon, Juan A.
2016-07-01
List of symbols; Preface; 1. Introduction; Part I. Geometric Tools: 2. Differential Geometry; 3. Spacetime spinors; 4. Space spinors; 5. Conformal Geometry; Part II. General Relativity and Conformal Geometry: 6. Conformal extensions of exact solutions; 7. Asymptotic simplicity; 8. The conformal Einstein field equations; 9. Matter models; 10. Asymptotics; Part III. Methods of PDE Theory: 11. The conformal constraint equations; 12. Methods of the theory of hyperbolic differential equations; 13. Hyperbolic reductions; 14. Causality and the Cauchy problem in General Relativity; Part IV. Applications: 15. De Sitter-like spacetimes; 16. Minkowski-like spacetimes; 17. Anti-de Sitter-like spacetimes; 18. Characteristic problems for the conformal field equations; 19. Static solutions; 20. Spatial infinity; 21. Perspectives; References; Index.
General Relativity by Kawaguchi geometry
Directory of Open Access Journals (Sweden)
Tanaka Erico
2013-09-01
Full Text Available We construct a parameterisation invariant Lagrange theory of fields up to second order by using multivector bundles and Kawaguchi geometry. In this setup, the spacetime is an dynamical object which is a submanifold of the greater manifold, and the actual spacetime is the solution of Euler-Lagrange equations. Such theory is a reasonable mathematical foundation to describe an extended theory of Einstein’s general relativity, and is capable of being a stage for unification with other physical fields.
Results from Numerical General Relativity
Baker, John G.
2011-01-01
For several years numerical simulations have been revealing the details of general relativity's predictions for the dynamical interactions of merging black holes. I will review what has been learned of the rich phenomenology of these mergers and the resulting gravitational wave signatures. These wave forms provide a potentially observable record of the powerful astronomical events, a central target of gravitational wave astronomy. Asymmetric radiation can produce a thrust on the system which may accelerate the single black hole resulting from the merger to high relative velocity.
General Relativity, Time and Determinism
Isenberg, James
2016-01-01
Einstein's theory of general relativity models the physical universe using spacetimes which satisfy Einstein's gravitational field equations. To date, Einstein's theory has been enormously successful in modeling observed gravitational phenomena, both at the astrophysical and the cosmological levels. The collection of spacetime solutions of Einstein's equations which have been effectively used for modeling the physical universe is a very small subset of the full set of solutions. Among this larger set, there are many spacetimes in which strange phenomena related to time are present: There are solutions containing regions in which determinism and the predictability of experimental outcomes breaks down (the Taub-NUT spacetimes), and there others in which the breakdown of determinism occurs everywhere (the G\\"odel universe). Should the existence of these strange solutions lead us to question the usefulness of Einstein's theory in modeling physical phenomena? Should it instead lead us to seriously search for stran...
Brownian Motion and General Relativity
O'Hara, Paul
2013-01-01
We construct a model of Brownian Motion on a pseudo-Riemannian manifold associated with general relativity. There are two aspects of the problem: The first is to define a sequence of stopping times associated with the Brownian "kicks" or impulses. The second is to define the dynamics of the particle along geodesics in between the Brownian kicks. When these two aspects are taken together, we can associate various distributions with the motion. We will find that the statistics of space-time events will obey a temperature dependent four dimensional Gaussian distribution defined over the quaternions which locally can be identified with Minkowski space. Analogously, the statistics of the 4-velocities will obey a kind of Maxwell-Juttner distribution. In contrast to previous work, our processes are characterized by two independent proper time variables defined with respect to the laboratory frame: a discrete one corresponding to the stopping times when the impulses take place and a continuous one corresponding to th...
Joore, I.K.; Reukers, D.F.M.; Donker, G.A.; Sighem, A.I. van; Coul, E.L. Op de; Prins, J.M.; Geerlings, S.E.; Barth, R.E.; Bergen, J.E. van; Broek, I.V. van den
2016-01-01
OBJECTIVES: Prior research has shown that Dutch general practitioners (GPs) do not always offer HIV testing and the number of undiagnosed HIV patients remains high. We aimed to further investigate the frequency and reasons for (not) testing for HIV and the contribution of GPs to the diagnosis of HIV
Joore, I.K.; Reukers, D.F.M.; Donker, G.A.; Sighem, A.I. van; Coul, E.L.M. Op de; Prins, J.M.; Geerlings, S.E.; Barth, S.R.E.; Bergen, J.E.A.M. van; Broek, I.V.F. van den
2016-01-01
Objectives: Prior research has shown that Dutch general practitioners (GPs) do not always offer HIV testing and the number of undiagnosed HIV patients remains high. We aimed to further investigate the frequency and reasons for (not) testing for HIV and the contribution of GPs to the diagnosis of HIV
Do, Tuan
2017-08-01
The short-period star S0-2 will reach its closest approach to the supermassive black hole at the Galactic center in 2018 at a separation of event will offer the first of a series of tests of General Relativity with stellar orbits around a supermassive black hole, an unexplored regime for tests of gravity. While S0-2 has been monitored for over 20 years with high angular resolution measurements from the ground, the astrometric reference frame is currently not stable enough for GR tests. The current reference frame is constructed using observations of 7 radio masers with narrow-field adaptive optics imaging from the ground. While this method provides a reference frame that is stable enough to measure the Keplerian orbits, it does not meet the more stringent requirements needed to measure post-Newtonian effects such as the precession of the periapse of the orbit. The small number of reference stars and the systematic errors associated with using large mosaics to observe these stars limit the accuracy of this method. We propose to construct a new reference frame for tests of gravity with WFC3-IR observations in Cycles 25, 26, & 27. When combined with absolute positions and proper motions from GAIA, these observations will provide the required precision in the reference frame. The WFC3-IR field of view has over 1000 times greater areal coverage than the narrow-field AO observations, providing 3 times the number of absolute reference sources from GAIA. The proposed observations build on a legacy of HST, GAIA, and adaptive optics data to open an era of gravitational science with orbits at the Galactic center.
The confrontation between general relativity and experiment
Will, C. M.
1980-01-01
Experiments that test the foundations of gravitation theory in terms of the Einstein equivalence principle are discussed along with solar system tests of general relativity at the post-Newtonian level. These include classical (light-deflection, time delay and perihelion shift) tests as well as tests of the strong equivalence principle. The binary pulsar is discussed as an extra-solar-system gravitational testing ground, and attention is given to the multipolarity of the waves and the amount of radiation damping. The mass function, periastron shift, redshift-Doppler parameter and rate of change of the orbit period (Pb) of the binary pulsar are also considered, and it is suggested that the measurement of Pb represents the first observation of the effects of gravitational radiation.
9 CFR 113.5 - General testing.
2010-01-01
... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false General testing. 113.5 Section 113.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES... General testing. (a) No biological product shall be released prior to the completion of tests prescribed...
General Relativity and John Archibald Wheeler
Ciufolini, Ignazio
2010-01-01
Observational and experimental data pertaining to gravity and cosmology are changing our view of the Universe. General relativity is a fundamental key for the understanding of these observations and its theory is undergoing a continuing enhancement of its intersection with observational and experimental data. These data include direct observations and experiments carried out in our solar system, among which there are direct gravitational wave astronomy, frame dragging and tests of gravitational theories from solar system and spacecraft observations. This book explores John Archibald Wheeler's seminal and enduring contributions in relativistic astrophysics and includes: the General Theory of Relativity and Wheeler's influence; recent developments in the confrontation of relativity with experiments; the theory describing gravitational radiation, and its detection in Earth-based and space-based interferometer detectors as well as in Earth-based bar detectors; the mathematical description of the initial value pro...
Action Principle for the Generalized Harmonic Formulation of General Relativity
Brown, J David
2010-01-01
An action principle for the generalized harmonic formulation of general relativity is presented. The action is a functional of the spacetime metric and the gauge source vector. The Z4 formulation of general relativity also can be defined by an action principle, as discussed by Bona, Bona--Casas and Palenzuela. The relationship between the generalized harmonic and Z4 actions is presented in detail.
General measure of Enterprising Tendency test
Caird, Sally
2013-01-01
The General measure of Enterprising Tendency test (GET2) is a measure of enterprising tendency developed for educational use and self assessment. It measures five entrepreneurial attributes, namely Need for achievement, Need for Autonomy, Creative Tendency, Calculated Risk taking and Locus of control, providing interpretation for this enterprising attributes. Since 1998 there has been considerable worldwide interest in the test of General Enterprising Tendency (GET test) developed and tested ...
Perturbative dynamics of quantum general relativity
Donoghue, John F.
1997-01-01
The quantum theory of General Relativity at low energy exists and is of the form called "effective field theory". In this talk I describe the ideas of effective field theory and its application to General Relativity.
General relativity with applications to astrophysics
Straumann, Norbert
2004-01-01
This text provides a comprehensive and timely introduction to general relativity The foundations of the theory in Part I are thoroughly developed together with the required mathematical background from differential geometry in Part III The six chapters in Part II are devoted to tests of general relativity and to many of its applications Binary pulsars are studied in considerable detail Much space is devoted to the study of compact objects, especially to black holes This includes a detailed derivation of the Kerr solution, Israel's proof of his uniqueness theorem, and derivations of the basic laws of black hole physics The final chapter of this part contains Witten's proof of the positive energy theorem The book addresses undergraduate and graduate students in physics, astrophysics and mathematics It is very well structured and should become a standard text for a modern treatment of gravitational physics The clear presentation of differential geometry makes it also useful for string theory and other fields of ...
Solar system dynamics in general relativity
Battista, Emmanuele; Esposito, Giampiero; Di Fiore, Luciano; Simo, Jules; Grado, Aniello
2016-01-01
Recent work in the literature has advocated using the Earth-Moon-planetoid Lagrangian points as observables, in order to test general relativity and effective field theories of gravity in the solar system. However, since the three-body problem of classical celestial mechanics is just an approximation of a much more complicated setting, where all celestial bodies in the solar system are subject to their mutual gravitational interactions, while solar radiation pressure and other sources of nongravitational perturbations also affect the dynamics, it is conceptually desirable to improve the current understanding of solar system dynamics in general relativity, as a first step towards a more accurate theoretical study of orbital motion in the weak-gravity regime. For this purpose, starting from the Einstein equations in the de Donder-Lanczos gauge, this paper arrives first at the Levi-Civita Lagrangian for the geodesic motion of celestial bodies, showing in detail under which conditions the effects of internal stru...
Numerical Hydrodynamics in General Relativity
Directory of Open Access Journals (Sweden)
Font José A.
2000-05-01
Full Text Available The current status of numerical solutions for the equations of ideal general relativistic hydrodynamics is reviewed. Different formulations of the equations are presented, with special mention of conservative and hyperbolic formulations well-adapted to advanced numerical methods. A representative sample of available numerical schemes is discussed and particular emphasis is paid to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. A comprehensive summary of relevant astrophysical simulations in strong gravitational fields, including gravitational collapse, accretion onto black holes and evolution of neutron stars, is also presented.
Numerical Hydrodynamics in General Relativity
Directory of Open Access Journals (Sweden)
Font José A.
2003-01-01
Full Text Available The current status of numerical solutions for the equations of ideal general relativistic hydrodynamics is reviewed. With respect to an earlier version of the article, the present update provides additional information on numerical schemes, and extends the discussion of astrophysical simulations in general relativistic hydrodynamics. Different formulations of the equations are presented, with special mention of conservative and hyperbolic formulations well-adapted to advanced numerical methods. A large sample of available numerical schemes is discussed, paying particular attention to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. A comprehensive summary of astrophysical simulations in strong gravitational fields is presented. These include gravitational collapse, accretion onto black holes, and hydrodynamical evolutions of neutron stars. The material contained in these sections highlights the numerical challenges of various representative simulations. It also follows, to some extent, the chronological development of the field, concerning advances on the formulation of the gravitational field and hydrodynamic equations and the numerical methodology designed to solve them.
A logic road from special relativity to general relativity
Andréka, Hajnal; Madarász, Judit X.; Németi, István; Székely, Gergely
2010-01-01
We present a streamlined axiom system of special relativity in first-order logic. From this axiom system we "derive" an axiom system of general relativity in two natural steps. We will also see how the axioms of special relativity transform into those of general relativity. This way we hope to make general relativity more accessible for the non-specialist.
Barendregt, C.S.; Laan, A.J.; Bongers, I.L.; van Nieuwenhuizen, Ch.
2016-01-01
This study investigated the longitudinal relation between general well-being and self-esteem of male adolescents with severe psychiatric disorders. Moreover, the transition out of secure residential care was studied. Adolescents (N = 172) were assessed three times with 6 months between each
General score tests for regression models incorporating 'robust' variance estimates
David Clayton; Joanna Howson
2002-01-01
Stata incorporates commands for carrying out two of the three general approaches to asymptotic significance testing in regression models, namely likelihood ratio (lrtest) and Wald tests (testparms). However, the third approach, using "score" tests, has no such general implementation. This omission is particularly serious when dealing with "clustered" data using the Huber-White approach. Here the likelihood ratio test is lost, leaving only the Wald test. This has relatively poor asymptotic pro...
Conformal methods in general relativity
Valiente Kroon, Juan A
2016-01-01
This book offers a systematic exposition of conformal methods and how they can be used to study the global properties of solutions to the equations of Einstein's theory of gravity. It shows that combining these ideas with differential geometry can elucidate the existence and stability of the basic solutions of the theory. Introducing the differential geometric, spinorial and PDE background required to gain a deep understanding of conformal methods, this text provides an accessible account of key results in mathematical relativity over the last thirty years, including the stability of de Sitter and Minkowski spacetimes. For graduate students and researchers, this self-contained account includes useful visual models to help the reader grasp abstract concepts and a list of further reading, making this the perfect reference companion on the topic.
Pulsar timing and general relativity
Backer, D. C.; Hellings, R. W.
1986-01-01
Techniques are described for accounting for relativistic effects in the analysis of pulsar signals. Design features of instrumentation used to achieve millisecond accuracy in the signal measurements are discussed. The accuracy of the data permits modeling the pulsar physical characteristics from the natural glitches in the emissions. Relativistic corrections are defined for adjusting for differences between the pulsar motion in its spacetime coordinate system relative to the terrestrial coordinate system, the earth's motion, and the gravitational potentials of solar system bodies. Modifications of the model to allow for a binary pulsar system are outlined, including treatment of the system as a point mass. Finally, a quadrupole model is presented for gravitational radiation and techniques are defined for using pulsars in the search for gravitational waves.
Point massive particle in General Relativity
Katanaev, M. O.
2013-10-01
It is well known that the Schwarzschild solution describes the gravitational field outside compact spherically symmetric mass distribution in General Relativity. In particular, it describes the gravitational field outside a point particle. Nevertheless, what is the exact solution of Einstein's equations with -type source corresponding to a point particle is not known. In the present paper, we prove that the Schwarzschild solution in isotropic coordinates is the asymptotically flat static spherically symmetric solution of Einstein's equations with -type energy-momentum tensor corresponding to a point particle. Solution of Einstein's equations is understood in the generalized sense after integration with a test function. Metric components are locally integrable functions for which nonlinear Einstein's equations are mathematically defined. The Schwarzschild solution in isotropic coordinates is locally isometric to the Schwarzschild solution in Schwarzschild coordinates but differs essentially globally. It is topologically trivial neglecting the world line of a point particle. Gravity attraction at large distances is replaced by repulsion at the particle neighborhood.
General relativity and mathematics; Relatividad General y Matematicas
Energy Technology Data Exchange (ETDEWEB)
Mars, M.
2015-07-01
General relativity is more than a theory of gravity, since any physical process occupies space and lasts for a time, forcing to reconcile that physical theory that describes what the dynamic nature of space-time itself. (Author)
Introduction to general relativity and cosmology
Berger, Mitchell A
2018-01-01
The textbook aims to present general relativity and modern cosmology in a friendly form suitable for advanced undergraduates. The text begins with a self-contained introduction to the theory of manifolds and then develops the tools needed to understand curved spaces and curved spacetimes. Special relativity can then be understood in a geometrical context, bypassing some of the difficulties students have when encountering relativistic effects (e.g. time dilation and length contraction) for the first time. The theory of curvature and its effects leads to the Einstein field equations and its classic tests in the precession of Mercury and the deflection of starlight. The second part of the book covers modern cosmology, starting with the evolution equations for the expansion of the universe. The microwave background, evidence for dark matter, and the clustering of galaxies are examined in detail.
On solar system dynamics in general relativity
Battista, Emmanuele; Esposito, Giampiero; di Fiore, Luciano; Dell'Agnello, Simone; Simo, Jules; Grado, Aniello
Recent work in the literature has advocated using the Earth-Moon-planetoid Lagrangian points as observables, in order to test general relativity and effective field theories of gravity in the solar system. However, since the three-body problem of classical celestial mechanics is just an approximation of a much more complicated setting, where all celestial bodies in the solar system are subject to their mutual gravitational interactions, while solar radiation pressure and other sources of nongravitational perturbations also affect the dynamics, it is conceptually desirable to improve the current understanding of solar system dynamics in general relativity, as a first step towards a more accurate theoretical study of orbital motion in the weak-gravity regime. For this purpose, starting from the Einstein equations in the de Donder-Lanczos gauge, this paper arrives first at the Levi-Civita Lagrangian for the geodesic motion of planets, showing in detail under which conditions the effects of internal structure and finite extension get canceled in general relativity to first post-Newtonian order. The resulting nonlinear ordinary differential equations for the motion of planets and satellites are solved for the Earth’s orbit about the Sun, written down in detail for the Sun-Earth-Moon system, and investigated for the case of planar motion of a body immersed in the gravitational field produced by the other bodies (e.g. planets with their satellites). At this stage, we prove an exact property, according to which the fourth-order time derivative of the original system leads to a linear system of ordinary differential equations. This opens an interesting perspective on forthcoming research on planetary motions in general relativity within the solar system, although the resulting equations remain a challenge for numerical and qualitative studies. Last, the evaluation of quantum corrections to location of collinear and noncollinear Lagrangian points for the planar restricted
Centennial of general relativity a celebration
2017-01-01
It has been over 100 years since the presentation of the Theory of General Relativity by Albert Einstein, in its final formulation, to the Royal Prussian Academy of Sciences. To celebrate 100 years of general relativity, World Scientific publishes this volume with a dual goal: to assess the current status of the field of general relativity in broad terms, and discuss future directions. The volume thus consists of broad overviews summarizing major developments over the past decades and their perspective contributions.
McClelland, Keri; Glazer, Kelsey Samantha; Overduin, James; Miskiewicz, Chris; Eney, Brian; Mouette, Jean
2018-01-01
We describe a student-led project to image two seventh-magnitude stars on either side of the Sun during the solar eclipse of August 21, 2017. Both stars were within one solar radius of the Sun, and according to Einstein’s theory of General Relativity, their positions would have been shifted away from the Sun by 1 arcsec. We observed the eclipse from three different sites along the path of totality (Lexington, South Carolina; Indian Valley, Idaho; Madras, Oregon). All three sites were clear, but the brightness of the solar corona has complicated the analysis. We present preliminary results using our best images from the site in Idaho.
General Relativity in the Undergraduate Physics Curriculum
Hartle, James B.
2005-01-01
Einstein's general relativity is increasingly important in contemporary physics on the frontiers of both the very largest distance scales (astrophysics and cosmology) and the very smallest(elementary particle physics). This paper makes the case for a `physics first' approach to introducing general relativity to undergraduate physics majors.
General Relativity in (1 + 1) Dimensions
Boozer, A. D.
2008-01-01
We describe a theory of gravity in (1 + 1) dimensions that can be thought of as a toy model of general relativity. The theory should be a useful pedagogical tool, because it is mathematically much simpler than general relativity but shares much of the same conceptual structure; in particular, it gives a simple illustration of how gravity arises…
Motivations for antigravity in General Relativity
Chardin, G.
1997-08-01
We present arguments showing that it is natural to interpret the negative mass part of the Kerr solution as representing the geometry experienced by antimatter. The C, P and T discrete transformations are considered for this geometry. The C and T properties of the proposed identification are found to be in agreement with the usual representation of antimatter. In addition, we conjecture a property of perfect stigmatism through Kerr wormholes which allows General Relativity to mimic antigravity. Kerr wormholes would then act as “supermirrors” reversing the C, P and T images of an object seen through it. This interpretation is subject to several experimental tests and able to provide an explanation, without any free parameter, of the “CP” violation observed in the neutral kaon system.
Motivations for antigravity in General Relativity
Energy Technology Data Exchange (ETDEWEB)
Chardin, G. [DSM/DAPNIA/SPP, CEN-Saclay (France)
1997-08-15
We present arguments showing that it is natural to interpret the negative mass part of the Kerr solution as representing the geometry experienced by antimatter. The C, P and T discrete transformations are considered for this geometry. The C and T properties of the proposed identification are found to be in agreement with the usual representation of antimatter. In addition, we conjecture a property of perfect stigmatism through Kerr wormholes which allows General Relativity to mimic antigravity. Kerr wormholes would then act as 'supermirrors' reversing the C, P and T images of an object seen through it. This interpretation is subject to several experimental tests and able to provide an explanation, without any free parameter, of the 'CP' violation observed in the neutral kaon system.
On thick domain walls in general relativity
Goetz, Guenter; Noetzold, Dirk
1989-01-01
Planar scalar field configurations in general relativity differ considerably from those in flat space. It is shown that static domain walls of finite thickness in curved space-time do not possess a reflection symmetry. At infinity, the space-time tends to the Taub vacuum on one side of the wall and to the Minkowski vacuum (Rindler space-time) on the other. Massive test particles are always accelerated towards the Minkowski side, i.e., domain walls are attractive on the Taub side, but repulsive on the Minkowski side (Taub-vacuum cleaner). It is also proved that the pressure in all directions is always negative. Finally, a brief comment is made concerning the possibility of infinite, i.e., bigger than horizon size, domain walls in our universe. All of the results are independent of the form of the potential V(phi) greater than or equal to 0 of the scalar field phi.
Larièpe, A; Moreau, L; Laborde, J; Bauland, C; Mezmouk, S; Décousset, L; Mary-Huard, T; Fiévet, J B; Gallais, A; Dubreuil, P; Charcosset, A
2017-02-01
General and specific combining abilities of maize hybrids between 288 inbred lines and three tester lines were highly related to population structure and genetic distance inferred from SNP data. Many studies have attempted to provide reliable and quick methods to identify promising parental lines and combinations in hybrid breeding programs. Since the 1950s, maize germplasm has been organized into heterotic groups to facilitate the exploitation of heterosis. Molecular markers have proven efficient tools to address the organization of genetic diversity and the relationship between lines or populations. The aim of the present work was to investigate to what extent marker-based evaluations of population structure and genetic distance may account for general (GCA) and specific (SCA) combining ability components in a population composed of 800 inter and intra-heterotic group hybrids obtained by crossing 288 inbred lines and three testers. Our results illustrate a strong effect of groups identified by population structure analysis on both GCA and SCA components. Including genetic distance between parental lines of hybrids in the model leads to a significant decrease of SCA variance component and an increase in GCA variance component for all the traits. The latter suggests that this approach can be efficient to better estimate the potential combining ability of inbred lines when crossed with unrelated lines, and limits the consequences of tester choice. Significant residual GCA and SCA variance components of models taking into account structure and/or genetic distance highlight the variation available for breeding programs within structure groups.
Van Patten, R. A.; Everitt, C. W. F.
1976-01-01
In 1918, Lense and Thirring calculated that a moon in orbit around a massive rotating planet would experience a nodal dragging effect due to general relativity. We describe an experiment to measure this effect by means of two counter-orbiting drag-free satellites in polar orbit about the earth. For a 2-1/2 year experiment, the measurement should approach an accuracy of 1%. An independent measurement of the geodetic precession of the orbit plane due to the motion about the sun may also be possible to about 10% accuracy. In addition to precision tracking data from existing ground stations, satellite-to-satellite Doppler data are taken at points of passing near the poles to yield an accurate measurement of the separation distance between the two satellites. New geophysical information on both earth harmonics and tidal effects is inherent in this polar ranging data.
Test Reviews: GEPT--General English Proficiency Test
Roever, Carsten; Pan, Yi-Ching
2008-01-01
The General English Proficiency Test (GEPT) was developed in 1999, commissioned by the Ministry of Education in Taiwan. The purpose of the test is to provide individuals with a gauge of their English language proficiency and assist employers and educational institutions in selection and placement. Also, it aims to encourage the study of English…
Black hole dynamics in general relativity
Indian Academy of Sciences (India)
Abstract. Basic features of dynamical black holes in full, non-linear general relativity are summarized in a pedagogical fashion. Qualitative properties of the evolution of various horizons follow directly from the celebrated Raychaudhuri equation.
Einstein and General Relativity: Historical Perspectives.
Chandrasekhar, S.
1979-01-01
This paper presented in the 1978 Oppenheimer Memorial Lecture at Los Alamos Scientific Laboratories on August 17, 1978, discusses Einstein's contributions to physics, in particular, his discovery of the general theory of relativity. (HM)
An observer principle for general relativity
Dupre, Maurice J
2014-01-01
We give a mathematical uniqueness theorem which in particular shows that symmetric tensors in general relativity are uniquely determined by their monomial functions on the light cone. Thus, for an observer to observe a tensor at an event in general relativity is to contract with the velocity vector of the observer, repeatedly to the rank of the tensor. Thus two symmetric tensors observed to be equal by all observers at a specific event are necessarily equal at that event.
A golden age of general relativity? Some remarks on the history of general relativity
Goenner, Hubert
2017-03-01
This article deals with the concepts "renaissance" and "low water mark between 1925 and 1955" of general relativity suggested in the literature. By empirical data, it is shown that no such period did exist. Research on general relativity continued continuously since the 1920s interrupted only by the second world war. On a broad scale, research on general relativity started only after 1945.
Teaching General Relativity to the Layperson
Egdall, Mark
2009-01-01
This paper describes a lay course on general relativity (GR) given at the Osher Lifelong Learning Institute at Florida International University. It is presented in six hour-and-a-half weekly sessions. Other courses offered by the author include special relativity (which precedes the course described here), quantum theory, and cosmology. Students…
Maximilien Brice
2010-01-01
26th August 2010 - World Meteorological Organization Secretary-General M. Jarraud signing the guest book with CERN Director-General R. Heuer and visiting the LHC superconducting magnet test hall with Technology Department Head F. Bordry; throughout accompanied by M. Bona, CERN Relations with International Organisations
Relational Coordination in Danish General Practice
DEFF Research Database (Denmark)
Lundstrøm, Sanne Lykke
and relationship networks through which work is coordinated across functional and organisational boundaries. Previous studies have shown that relational coordination is positively associated with delivery of care for patients with chronic illness. Organisational social capital is used when analysing...... the psychosocial work environment in organisations, and is seen as a powerful resources for improving organisational performance. Relational coordination and organisational social capital may oer new insight and opportunities for general practice to learn. General practice provides cost-efficient, first......This PhD dissertation is a product of my PhD project carried out in collaboration between DTU Management Engineering, The Technical University of Denmark, Research Unit for General Practice at University of Southern Denmark, and Research Unit for General Practice at University of Copenhagen...
Introduction to 2-spinors in general relativity
O'Donnell, Peter
2003-01-01
This book deals with 2-spinors in general relativity, beginning by developing spinors in a geometrical way rather than using representation theory, which can be a little abstract. This gives the reader greater physical intuition into the way in which spinors behave. The book concentrates on the algebra and calculus of spinors connected with curved space-time. Many of the well-known tensor fields in general relativity are shown to have spinor counterparts. An analysis of the Lanczos spinor concludes the book, and some of the techniques so far encountered are applied to this. Exercises play an i
Toposes in General Theory of Relativity
Guts, Alexandr K.; Grinkevich, Egor B.
1996-01-01
We study in this paper different topos-theoretical approaches to the problem of construction of General Theory of Relativity. In general case the resulting space-time theory will be non-classical, different from that of the usual Einstein theory of space-time. This is a new theory of space-time, created in a purely logical manner. Four possibitities are investigated: axiomatic approach to causal theory of space-time, the smooth toposes as a models of Theory of Relativity, Synthetic Theory of ...
2011-09-14
... General Service Fluorescent Lamps, General Service Incandescent Lamps, and Incandescent Reflector Lamps... proposing to revise its test procedures for general service fluorescent lamps (GSFLs) and general service... Procedures for General Service Fluorescent Lamps, General Service Incandescent Lamps, and Incandescent...
Black hole dynamics in general relativity
Indian Academy of Sciences (India)
69, No. 1. — journal of. July 2007 physics pp. 77–92. Black hole dynamics in general relativity. ABHAY ASHTEKAR. 1,2. 1. Institute for Gravitational Physics and Geometry, Physics Department,. Penn State University, University Park, PA 16802, USA. 2. Institute for Theoretical Physics, University of Utrecht, Princetonplein 5,.
Summary of classical general relativity workshop
Indian Academy of Sciences (India)
In the classical general relativity workshop, ten lectures were presented on various topics. The topics included aspects of black-hole physics, gravitational collapse and the formation of black holes, specific stellar models like a superdense star, method of extracting solutions by exploiting Noether symmetry, brane world and.
The rocket problem in general relativity
Henriques, Pedro G
2011-01-01
We derive the covariant optimality conditions for rocket trajectories in general relativity, with and without a bound on the magnitude of the proper acceleration. The resulting theory is then applied to solve two specific problems: the minimum fuel consumption transfer between two galaxies in a FLRW model, and between two stable circular orbits in the Schwarzschild spacetime.
Generalization of Gibbs Entropy and Thermodynamic Relation
Park, Jun Chul
2010-01-01
In this paper, we extend Gibbs's approach of quasi-equilibrium thermodynamic processes, and calculate the microscopic expression of entropy for general non-equilibrium thermodynamic processes. Also, we analyze the formal structure of thermodynamic relation in non-equilibrium thermodynamic processes.
General relativity at 75: how right was einstein?
Will, C M
1990-11-09
The status of experimental tests of general relativity is reviewed on the occasion of its 75th anniversary. Einstein's equivalence principle is well supported by experiments such as the Eötvös experiment, tests of special relativity, and the gravitational redshift experiment. Tests of general relativity have reached high precision, including the light deflection and the perihelion advance of Mercury, proposed by Einstein 75 years ago, and new tests such as the Shapiro time delay and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected to an accuracy of 1 percent on the basis of measurements of the binary pulsar. The status of the "fifth force" is discussed, along with the frontiers of experimental relativity, including proposals for testing relativistic gravity with advanced technology and spacecraft.
BOOK REVIEW: Modern Canonical Quantum General Relativity
Kiefer, Claus
2008-06-01
The open problem of constructing a consistent and experimentally tested quantum theory of the gravitational field has its place at the heart of fundamental physics. The main approaches can be roughly divided into two classes: either one seeks a unified quantum framework of all interactions or one starts with a direct quantization of general relativity. In the first class, string theory (M-theory) is the only known example. In the second class, one can make an additional methodological distinction: while covariant approaches such as path-integral quantization use the four-dimensional metric as an essential ingredient of their formalism, canonical approaches start with a foliation of spacetime into spacelike hypersurfaces in order to arrive at a Hamiltonian formulation. The present book is devoted to one of the canonical approaches—loop quantum gravity. It is named modern canonical quantum general relativity by the author because it uses connections and holonomies as central variables, which are analogous to the variables used in Yang Mills theories. In fact, the canonically conjugate variables are a holonomy of a connection and the flux of a non-Abelian electric field. This has to be contrasted with the older geometrodynamical approach in which the metric of three-dimensional space and the second fundamental form are the fundamental entities, an approach which is still actively being pursued. It is the author's ambition to present loop quantum gravity in a way in which every step is formulated in a mathematically rigorous form. In his own words: 'loop quantum gravity is an attempt to construct a mathematically rigorous, background-independent, non-perturbative quantum field theory of Lorentzian general relativity and all known matter in four spacetime dimensions, not more and not less'. The formal Leitmotiv of loop quantum gravity is background independence. Non-gravitational theories are usually quantized on a given non-dynamical background. In contrast, due to
A short course in general relativity
Foster, James
2006-01-01
Suitable for a one-semester course in general relativity for senior undergraduates or beginning graduate students, this text clarifies the mathematical aspects of Einstein's theory of relativity without sacrificing physical understanding. The text begins with an exposition of those aspects of tensor calculus and differential geometry needed for a proper treatment of the subject. The discussion then turns to the spacetime of general relativity and to geodesic motion. A brief consideration of the field equations is followed by a discussion of physics in the vicinity of massive objects, including an elementary treatment of black holes and rotating objects. The main text concludes with introductory chapters on gravitational radiation and cosmology. This new third edition has been updated to take account of fresh observational evidence and experiments. It includes new sections on the Kerr solution (in Chapter 4) and cosmological speeds of recession (in Chapter 6). A more mathematical treatment of tensors and manif...
Wu, Ning
2006-01-01
For a long time, it is generally believed that spin-spin interactions can only exist in a theory where Lorentz symmetry is gauged, and a theory with spin-spin interactions is not perturbatively renormalizable. But this is not true. By studying the motion of a spinning particle in gravitational field, it is found that there exist spin-spin interactions in gauge theory of gravity. Its mechanism is that a spinning particle will generate gravitomagnetic field in space-time, and this gravitomagnet...
Generalized F test and generalized deviance test in two-way ANOVA models for randomized trials.
Shen, Juan; He, Xuming
2014-01-01
We consider the problem of detecting treatment effects in a randomized trial in the presence of an additional covariate. By reexpressing a two-way analysis of variance (ANOVA) model in a logistic regression framework, we derive generalized F tests and generalized deviance tests, which provide better power in detecting common location-scale changes of treatment outcomes than the classical F test. The null distributions of the test statistics are independent of the nuisance parameters in the models, so the critical values can be easily determined by Monte Carlo methods. We use simulation studies to demonstrate how the proposed tests perform compared with the classical F test. We also use data from a clinical study to illustrate possible savings in sample sizes.
Gravity An Introduction to Einstein's General Relativity
Hartle, James B
2003-01-01
The aim of this groundbreaking new book is to bring general relativity into the undergraduate curriculum and make this fundamental theory accessible to all physics majors. Using a "physics first" approach to the subject, renowned relativist James B. Hartle provides a fluent and accessible introduction that uses a minimum of new mathematics and is illustrated with a wealth of exciting applications. The emphasis is on the exciting phenomena of gravitational physics and the growing connection between theory and observation. The Global Positioning System, black holes, X-ray sources, pulsars, quasars, gravitational waves, the Big Bang, and the large scale structure of the universe are used to illustrate the widespread role of how general relativity describes a wealth of everyday and exotic phenomena.
Generalizing the spatial relative risk function.
Sarojinie Fernando, W T P; Hazelton, Martin L
2014-04-01
The spatial relative risk function is defined as the ratio of densities describing respectively the spatial distribution of cases and controls. It has proven to be an effective tool for visualizing spatial variation in risk in many epidemiological applications over the past 20 years. We discuss the generalization of this function to spatio-temporal case-control data, and also to situations where there are covariates available that may affect the spatial patterns of disease. We examine estimation of the generalized relative risk functions using kernel smoothing, including asymptotic theory and data-driven bandwidth selection. We also consider construction of tolerance contours. Our methods are illustrated on spatio-temporal data describing the 2001 outbreak of foot-and-mouth disease in the United Kingdom, with farm size as a covariate. Copyright © 2013 Elsevier Ltd. All rights reserved.
Special relativity, electrodynamics, and general relativity from Newton to Einstein
Kogut, John B
2018-01-01
Special Relativity, Electrodynamics and General Relativity: From Newton to Einstein, Second Edition, is intended to teach (astro)physics, astronomy, and cosmology students how to think about special and general relativity in a fundamental, but accessible, way. Designed to render any reader a "master of relativity," everything on the subject is comprehensible and derivable from first principles. The book emphasizes problem solving, contains abundant problem sets, and is conveniently organized to meet the needs of both student and instructor. Fully revised, updated and expanded second edition Includes new chapters on magnetism as a consequence of relativity and electromagnetism Contains many improved and more engaging figures Uses less algebra resulting in more efficient derivations Enlarged discussion of dynamics and the relativistic version of Newton's second law
Relativity the special and the general theory
Einstein, Albert
2015-01-01
After completing the final version of his general theory of relativity in November 1915, Albert Einstein wrote a book about relativity for a popular audience. His intention was "to give an exact insight into the theory of relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical apparatus of theoretical physics." The book remains one of the most lucid explanations of the special and general theories ever written. In the early 1920s alone, it was translated into ten languages, and fifteen editions in the original German appeared over the course of Einstein's lifetime. This new edition of Einstein's celebrated book features an authoritative English translation of the text along with an introduction and a reading companion by Hanoch Gutfreund and Jürgen Renn that examines the evolution of Einstein's thinking and casts his ideas in a broader present-day context. A special chapter explores the history...
The confrontation between general relativity and experiment
Indian Academy of Sciences (India)
The best tests of local Lorentz invariance are the 'mass anisotropy' or 'Hughes–. Drever' experiments. A simple way of interpreting these experiments is to suppose that a non-metric coupling to the electromagnetic interactions results in a change in the speed of electromagnetic radiation c relative to the limiting speed of the.
Premetric equivalent of general relativity: Teleparallelism
Itin, Yakov; Hehl, Friedrich W.; Obukhov, Yuri N.
2017-04-01
In general relativity (GR), the metric tensor of spacetime is essential since it represents the gravitational potential. In other gauge theories (such as electromagnetism), the so-called premetric approach succeeds in separating the purely topological field equation from the metric-dependent constitutive law. We show here that GR allows for a premetric formulation, too. For this purpose, we apply the teleparallel approach of gravity, which represents GR as a gauge theory based on the translation group. We formulate the metric-free topological field equation and a general linear constitutive law between the basic field variables. The requirement of local Lorentz invariance turns the model into a full equivalent of GR. Our approach opens a way for a natural extension of GR to diverse geometrical structures of spacetime.
General Relativity As an Aether Theory
Dupre, Maurice J
2010-01-01
Most early twentieth century relativists --- Lorentz, Einstein, Eddington, for examples --- claimed that general relativity was merely a theory of the aether. We shall confirm this claim by deriving the Einstein equations using aether theory. We shall use a combination of Lorentz's and Kelvin's conception of the aether. Our derivation of the Einstein equations will not use the vanishing of the covariant divergence of the stress-energy tensor, but instead equate the Ricci tensor to the sum of the usual stress-energy tensor and a stress-energy tensor for the aether, a tensor based on Kelvin's aether theory. A crucial first step is generalizing the Cartan formalism of Newtonian gravity to allow spatial curvature, as conjectured by Gauss and Riemann.
Numerical Hydrodynamics and Magnetohydrodynamics in General Relativity
Directory of Open Access Journals (Sweden)
Font José A.
2008-09-01
Full Text Available This article presents a comprehensive overview of numerical hydrodynamics and magnetohydrodynamics (MHD in general relativity. Some significant additions have been incorporated with respect to the previous two versions of this review (2000, 2003, most notably the coverage of general-relativistic MHD, a field in which remarkable activity and progress has occurred in the last few years. Correspondingly, the discussion of astrophysical simulations in general-relativistic hydrodynamics is enlarged to account for recent relevant advances, while those dealing with general-relativistic MHD are amply covered in this review for the first time. The basic outline of this article is nevertheless similar to its earlier versions, save for the addition of MHD-related issues throughout. Hence, different formulations of both the hydrodynamics and MHD equations are presented, with special mention of conservative and hyperbolic formulations well adapted to advanced numerical methods. A large sample of numerical approaches for solving such hyperbolic systems of equations is discussed, paying particular attention to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. As previously stated, a comprehensive summary of astrophysical simulations in strong gravitational fields is also presented. These are detailed in three basic sections, namely gravitational collapse, black-hole accretion, and neutron-star evolutions; despite the boundaries, these sections may (and in fact do overlap throughout the discussion. The material contained in these sections highlights the numerical challenges of various representative simulations. It also follows, to some extent, the chronological development of the field, concerning advances in the formulation of the gravitational field, hydrodynamics and MHD equations and the numerical methodology designed to solve them. To keep the length of this article reasonable
Numerical Hydrodynamics and Magnetohydrodynamics in General Relativity.
Font, José A
2008-01-01
This article presents a comprehensive overview of numerical hydrodynamics and magneto-hydrodynamics (MHD) in general relativity. Some significant additions have been incorporated with respect to the previous two versions of this review (2000, 2003), most notably the coverage of general-relativistic MHD, a field in which remarkable activity and progress has occurred in the last few years. Correspondingly, the discussion of astrophysical simulations in general-relativistic hydrodynamics is enlarged to account for recent relevant advances, while those dealing with general-relativistic MHD are amply covered in this review for the first time. The basic outline of this article is nevertheless similar to its earlier versions, save for the addition of MHD-related issues throughout. Hence, different formulations of both the hydrodynamics and MHD equations are presented, with special mention of conservative and hyperbolic formulations well adapted to advanced numerical methods. A large sample of numerical approaches for solving such hyperbolic systems of equations is discussed, paying particular attention to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. As previously stated, a comprehensive summary of astrophysical simulations in strong gravitational fields is also presented. These are detailed in three basic sections, namely gravitational collapse, black-hole accretion, and neutron-star evolutions; despite the boundaries, these sections may (and in fact do) overlap throughout the discussion. The material contained in these sections highlights the numerical challenges of various representative simulations. It also follows, to some extent, the chronological development of the field, concerning advances in the formulation of the gravitational field, hydrodynamics and MHD equations and the numerical methodology designed to solve them. To keep the length of this article reasonable, an effort has
The mathematical theory of general relativity
Katkar, L N
2014-01-01
This book is prepared for M. Sc. Students of Mathematics and Physics. The aim of writing this book is to give the reader a feeling for the necessity and beauty of the laws of general relativity. The contents of the book will attract both mathematicians and physicists which provides motivation and applications of many ideas and powerful mathematical methods of modern analysis and differential geometry. An attempt has been made to make the presentation comprehensive, rigorous and yet simple. Most calculations and transformations have been carried out in great detail. KEY FEATURE: Numerous solved examples using the well known mathematical techniques viz., the tensors and the differential forms in each chapter.
Modelling of general relativity phenomena with photonics
Fernández Núñez, Isabel Dèlia
2014-01-01
Treball final de màster oficial fet en col·laboració amb Universitat Autònoma de Barcelona (UAB), Universitat de Barcelona (UB) i Institut de Ciències Fotòniques (ICFO) [ANGLÈS] Metamaterials are man-made artificial materials whose electromagnetic parameters the permittivity and permeability are determined by its internal structure rather than their substance. An analogy between the electrodynamics of these new materials and general relativity is discussed. Based on this analogy, the possi...
Time asymmetric extensions of general relativity
Cortes, Marina; Smolin, Lee
2015-01-01
We describe a class of modified gravity theories that deform general relativity in a way that breaks time reversal invariance and, very mildly, locality. The algebra of constraints, local physical degrees of freedom, and their linearized equations of motion, are unchanged, yet observable effects may be present on cosmological scales, which have implications for the early history of the universe. This is achieved in the Hamiltonian framework, in a way that requires the constant mean curvature gauge conditions and is, hence, inspired by shape dynamics.
100 Years of General Theory of Relativity
2015-01-01
The Symposium will celebrate the 100th anniversary of Einstein's four papers on General Relativity, which he submitted to the Preussische Akademie der Wissenschaften during November 1915. A review of the history of the creation of Einstein's masterpiece, from its roots in Bern, the important steps forward in Zurich and up to its completion in Berlin will be followed by an extensive overview covering the later developments up to present-day research. This will include discussions on the impact of the theory on our view of the universe as well as on progress in technology for everyday life.
New Area Law in General Relativity.
Bousso, Raphael; Engelhardt, Netta
2015-08-21
We report a new area law in general relativity. A future holographic screen is a hypersurface foliated by marginally trapped surfaces. We show that their area increases monotonically along the foliation. Future holographic screens can easily be found in collapsing stars and near a big crunch. Past holographic screens exist in any expanding universe and obey a similar theorem, yielding the first rigorous area law in big bang cosmology. Unlike event horizons, these objects can be identified at finite time and without reference to an asymptotic boundary. The Bousso bound is not used, but it naturally suggests a thermodynamic interpretation of our result.
42 CFR 84.99 - Man tests; testing conditions; general requirements.
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Man tests; testing conditions; general requirements. 84.99 Section 84.99 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.99...
Software Testing Overview on Different Generalization Levels
Kuļešovs, Ivans; Arnicane, Vineta; Arnicans, Guntis; Borzovs, Juris
2013-01-01
There are many different views on software testing co-exist even within the borders of one organization. That is why we have decided to prepare software testing overview on metalevel indicating main influencers that make this difference. While gathering the details about meta-level elements we have performed some structuring of elements from lower level of software testing such as testing oracles and testing approaches, methods, and techniques. The overview preparation has resu...
Von Neumann's quantization of general relativity
Arbuzov, A. B.; Cherny, A. Yu.; Cirilo-Lombardo, D. J.; Nazmitdinov, R. G.; Han, Nguyen Suan; Pavlov, A. E.; Pervushin, V. N.; Zakharov, A. F.
2017-05-01
Von Neumann's procedure is applied to quantizing general relativity. Initial data for dynamical variables in the Planck epoch, where the Hubble parameter value coincided with the Planck mass are quantized. These initial data are defined in terms of the Fock orthogonal simplex in the tangent Minkowski spacetime and the Dirac conformal interval. The Einstein cosmological principle is used to average the logarithm of the determinant of the spatial metric over the spatial volume of the visible Universe. The splitting of general coordinate transformations into diffeomorphisms and transformations of the initial data is introduced. In accordance with von Neumann's procedure, the vacuum state is treated is a quantum ensemble that is degenerate in quantum numbers of nonvacuum states. The distribution of the vacuum state leads to the Casimir effect in gravidynamics in just the same way as in electrodynamics. The generating functional for perturbation theory in gravidynamics is found by solving the quantum energy constraint. The applicability range of gravidynamics is discussed along with the possibility of employing this theory to interpret modern observational data.
An Introduction to General Relativity and Cosmology
Plebanski, Jerzy; Krasinski, Andrzej
2012-09-01
1. How the theory of relativity came into being (a brief historical sketch); Part I. Elements of Differential Geometry: 2. A short sketch of two-dimensional differential geometries; 3. Tensors, tensor densities; 4. Covariant derivatives; 5. Parallel transport and geodesic lines; 6. Curvature of a manifold: flat manifolds; 7. Riemannian geometry; 8. Symmetries of Rieman spaces, invariance of tensors; 9. Methods to calculate the curvature quickly - Cartan forms and algebraic computer programs; 10. The spatially homogeneous Bianchi-type spacetimes; 11. The Petrov classification by the spinor method; Part II. The Gravitation Theory: 12. The Einstein equations and the sources of a gravitational field; 13. The Maxwell and Einstein-Maxwell equations and the Kaluza-Klein theory; 14. Spherically symmetric gravitational field of isolated objects; 15. Relativistic hydrodynamics and thermodynamics; 16. Relativistic cosmology I: general geometry; 17. Relativistic cosmology II: the Robertson-Walker geometry; 18. Relativistic cosmology III: the Lemaître-Tolman geometry; 19. Relativistic cosmology IV: generalisations of L-T and related geometries; 20. The Kerr solution; 21. Subjects omitted in this book; References.
Moisture related test protocols for HVS testing
CSIR Research Space (South Africa)
Denneman, E
2008-10-01
Full Text Available In order to provide guidance on the possible methodologies for evaluating specifically moisture related pavement response using the Heavy Vehicle Simulator (HVS), this paper describes the objectives, potential effects and available methods...
Dynamic Administration of a General Intelligence Test.
1991-01-01
Learning and Individual Differences , Vol...reOrOxlucion ,m any sorm reserved ISSN �-6080 124 LEARNING AND INDIVIDUAL DIFFERENCES VOLUME 3. ,UMER 2. 11 results show that dynamic testing (involving cues...days of pilot testing during which proctors determined the typical item solution latencies. 126 LEARNING AND INDIVIDUAL DIFFERENCES vOLuM 3. NULiEA
General relativity in hyperextended chaotic inflation
Susperregi, M
1999-01-01
We address the question of whether general relativity (GR) is an 'attractor' in a universe governed by hyperextended chaotic inflation (HCI). HCI results from the combination of chaotic inflation and a theory of gravity that is equivalent to Brans-Dicke (BD) gravity within the horizon scale. Globally it differs from BD gravity in that omega is a dynamical parameter that depends on the BD field PHI. As is well known, GR is recovered from BD gravity in the limit omega -> infinity and large values of PHI. A substantial difficulty in studying HCI is to find and adequate model for the functional dependence of omega. In this paper we employ the analogy between the BD field in HCI and the dilaton field in string theory to construct an ansatz for omega(PHI). The string theory analogy is based on the principle of least coupling of Polyakov and Damour which states that the dilaton and metric fields decouple asymptotically. Based on this principle, we investigate the question of whether a large value of omega is predomi...
Particle Pair Production in Cosmological General Relativity
Oliveira, Firmin J
2012-01-01
The Cosmological General Relativity of Carmeli, a 5-dimensional theory of time, space and velocity, predicts the existence of an acceleration $a_0 = c / \\tau$ due to the expansion of the universe, where $c$ is the speed of light in vacuum, $\\tau = 1/h$ is the Hubble-Carmeli time constant, where $h$ is the Hubble constant at zero distance and no gravity. The Carmeli force on a particle of mass $m$ is $F_c = m a_0$, a fifth force in nature. The fields resulting from the solution of the Einstein field equations in 5-D CGR and the Carmeli force are used to hypothesize the production of a particle and its antiparticle. The mass of each particle is found to be $m=\\tau c^3 / 4 G$, where $G$ is Newton's constant. The vacuum mass density derived from the physics is $\\rho_{vac} = -3/8 \\pi G \\tau^2$. The cosmological constant is then given by $\\Lambda = 3 / \\tau^2$. We derive an expression for $\\tau$ given by $\\tau = \\sqrt{(45 \\zeta (1 - g) c^3 \\hbar^3) / (4\\pi^3 G \\mu \\alpha^2 k^3 \\beta^3 T^3)}$, where $\\zeta$ is the b...
Einstein's Jury The Race to Test Relativity
Crelinsten, Jeffrey
2006-01-01
Einstein's Jury is the dramatic story of how astronomers in Germany, England, and America competed to test Einstein's developing theory of relativity. Weaving a rich narrative based on extensive archival research, Jeffrey Crelinsten shows how these early scientific debates shaped cultural attitudes we hold today. The book examines Einstein's theory of general relativity through the eyes of astronomers, many of whom were not convinced of the legitimacy of Einstein's startling breakthrough. These were individuals with international reputations to uphold and benefactors and shareholders to p
Generalization of Pain-Related Fear Based on Conceptual Knowledge.
Meulders, Ann; Vandael, Kristof; Vlaeyen, Johan W S
2017-05-01
Increasing evidence suggests that pain-related fear is key to the transition from acute to chronic pain. Previous research has shown that perceptual similarity with a pain-associated movement fosters the generalization of fear to novel movements. Perceptual generalization of pain-related fear is adaptive as it enables individuals to extrapolate the threat value of one movement to another without the necessity to learn anew. However, excessive spreading of fear to safe movements may become maladaptive and may lead to sustained anxiety, dysfunctional avoidance behaviors, and severe disability. A hallmark of human cognition is the ability to extract conceptual knowledge from a learning episode as well. Although this conceptual pathway may be important to understand fear generalization in chronic pain, research on this topic is lacking. We investigated acquisition and generalization of concept-based pain-related fear. During acquisition, unique exemplars of one action category (CS+; e.g., opening boxes) were followed by pain, whereas exemplars of another action category (CS-; e.g., closing boxes) were not. Subsequently, spreading of pain-related fear to novel exemplars of both action categories was tested. Participants learned to expect the pain to occur and reported more pain-related fear to the exemplars of the CS+ category compared with those of the CS- category. During generalization, fear and expectancy generalized to novel exemplars of the CS+ category, but not to the CS- category. This pattern was not corroborated in the eyeblink startle measures. This is the first study that demonstrates that pain-related fear can be acquired and generalized based on conceptual knowledge. Copyright © 2016. Published by Elsevier Ltd.
General Relativity Revisited: Generalized Nordstr\\"om Theory
Bengtsson, Johan
2016-01-01
In 1945 Einstein concluded that [1]: 'The present theory of relativity is based on a division of physical reality into a metric field (gravitation) on the one hand, and into an electromagnetic field and matter on the other hand. In reality space will probably be of a uniform character and the present theory be valid only as a limiting case. For large densities of field and of matter, the field equations and even the field variables which enter into them will have no real significance.'. The dichotomy can be resolved by introducing a scalar field/potential algebraically related to the Ricci tensor for which the corresponding metric is free of additional singularities. Hence, although a fundamentally nonlinear theory, the scalar field/potential provides an analytic framework for interacting particles; described by linear superposition. The stress tensor for the scalar field includes both the sources of and the energy-momentum for the gravitational field, and has zero covariant and ordinary divergence. Hence, th...
Gamma and Related Functions Generalized for Sequences
Ollerton, R. L.
2008-01-01
Given a sequence g[subscript k] greater than 0, the "g-factorial" product [big product][superscript k] [subscript i=1] g[subscript i] is extended from integer k to real x by generalizing properties of the gamma function [Gamma](x). The Euler-Mascheroni constant [gamma] and the beta and zeta functions are also generalized. Specific examples include…
Gravitational Wave in Linear General Relativity
Cubillos, D. J.
2017-07-01
General relativity is the best theory currently available to describe the interaction due to gravity. Within Albert Einstein's field equations this interaction is described by means of the spatiotemporal curvature generated by the matter-energy content in the universe. Weyl worked on the existence of perturbations of the curvature of space-time that propagate at the speed of light, which are known as Gravitational Waves, obtained to a first approximation through the linearization of the field equations of Einstein. Weyl's solution consists of taking the field equations in a vacuum and disturbing the metric, using the Minkowski metric slightly perturbed by a factor ɛ greater than zero but much smaller than one. If the feedback effect of the field is neglected, it can be considered as a weak field solution. After introducing the disturbed metric and ignoring ɛ terms of order greater than one, we can find the linearized field equations in terms of the perturbation, which can then be expressed in terms of the Dalambertian operator of the perturbation equalized to zero. This is analogous to the linear wave equation in classical mechanics, which can be interpreted by saying that gravitational effects propagate as waves at the speed of light. In addition to this, by studying the motion of a particle affected by this perturbation through the geodesic equation can show the transversal character of the gravitational wave and its two possible states of polarization. It can be shown that the energy carried by the wave is of the order of 1/c5 where c is the speed of light, which explains that its effects on matter are very small and very difficult to detect.
A century of general relativity: astrophysics and cosmology.
Blandford, R D
2015-03-06
One hundred years after its birth, general relativity has become a highly successful physical theory in the sense that it has passed a large number of experimental and observational tests and finds extensive application to a wide variety of cosmic phenomena. It remains an active area of research as new tests are on the way, epitomized by the exciting prospect of detecting gravitational waves from merging black holes. General relativity is the essential foundation of the standard model of cosmology and underlies our description of the black holes and neutron stars that are ultimately responsible for the most powerful and dramatic cosmic sources. Its interface with physics on the smallest and largest scales will continue to provide fertile areas of investigation in its next century. Copyright © 2015, American Association for the Advancement of Science.
Introduction to General Relativity and Black Holes (3/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (1/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (5/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (2/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (4/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Electromagnetic Radiation Reaction in General Relativity.
O'Donnell, Nuala
Available from UMI in association with The British Library. This thesis examines the electromagnetic radiation reaction felt by a charged body falling freely in an external gravitational field in general relativity. The original objective was to find a new derivation of the radiation reaction force F^{i} of DeWitt and DeWitt^1 which was calculated for the special case of a point charge falling in slow motion in a weak, static gravitational field: F ^{i} = {2over 3}e^2R^{i}_{0j0 }v^{j}. This may be thought of as a local expression since it involves the particle's velocity v^{j } and the local Riemann curvature tensor R ^{i}_{0j0}. Its derivation involves integrals over the whole history of the particle, covering distances of approximately the length scale on which R^{i}_{0j0 } changes. This is different from calculations of the Abraham-Lorentz force of flat space-time involving integrals over distances only a few times the size of the charge. This work was motivated by the wish to find a "local" derivation of the local reaction force. Using Schutz's^2 local initial value method to solve the problem of a charged, rigid, spherically symmetric body moving in an external gravitational field of arbitrary metric. Calculations are done in a Riemann normal coordinate system ^3 and are only valid in a normal neighbourhood of the origin, where geodesics have not begun to cross one another. We solve Maxwell's equations for the self -force by making a slow-motion approximation and keeping terms to first order only in the Riemann tensor and velocity. It is surprising that we find no local radiation reaction. Consider two particles in a static spacetime with the same initial conditions at t = 0. Particle A is that of DeWitt and DeWitt; it feels a reaction force F^{i} = {2over 3}e^2R^{i }_{0j0}v^{j}. Particle B is accelerated from rest to the same small velocity; it feels no reaction force. The two particles therefore follow different trajectories. We conclude that there is a
General Information about AIDS-Related Lymphoma
... spreading to the central nervous system (CNS). For treatment, AIDS-related lymphomas are grouped based on where they ... only to patients who have not started treatment. Treatment of AIDS-related lymphoma combines treatment of the lymphoma with ...
The New Aspects of General Relativity
Rabounski, D
2004-01-01
The study represents developments of A. L. Zelmanov's mathematical apparatus of chronometric invariants (physical observable values in General Relaivity), defined as the projections of four-dimensional values on time lines and the spatial section. Employing the mathematical methods gives new directions in the theory of fields.
2012-01-27
... Fluorescent Lamps, General Service Incandescent Lamps, and Incandescent Reflector Lamps AGENCY: Office of... the test procedures for general service fluorescent lamps (GSFLs), general service incandescent lamps... Standards Incorporated by Reference 1. ANSI C78.81-2010 for General Service Fluorescent Lamps 2. IES LM-9...
General Theory of Relativity: Will It Survive the Next Decade?
Bertolami, Orfeu; Paramos, Jorge; Turyshev, Slava G.
2006-01-01
The nature of gravity is fundamental to our understanding of our own solar system, the galaxy and the structure and evolution of the Universe. Einstein's general theory of relativity is the standard model that is used for almost ninety years to describe gravitational phenomena on these various scales. We review the foundations of general relativity, discuss the recent progress in the tests of relativistic gravity, and present motivations for high-accuracy gravitational experiments in space. We also summarize the science objectives and technology needs for the laboratory experiments in space with laboratory being the entire solar system. We discuss the advances in our understanding of fundamental physics anticipated in the near future and evaluate discovery potential for the recently proposed gravitational experiments.
Matroidal Structure of Generalized Rough Sets Based on Tolerance Relations
Directory of Open Access Journals (Sweden)
Hui Li
2014-01-01
of the generalized rough set based on the tolerance relation. The matroid can also induce a new relation. We investigate the connection between the original tolerance relation and the induced relation.
40 CFR 86.130-96 - Test sequence; general requirements.
2010-07-01
... and the running loss test are not required. (b) The vehicle test for fuel spitback during fuel... to prevent abnormal fuel distribution. (e) If tests are invalidated after collection of emission data... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Test sequence; general requirements...
Test Performance Related Dysfunctional Beliefs
Directory of Open Access Journals (Sweden)
Recep TÜTÜNCÜ
2012-11-01
Full Text Available Objective: Examinations by using tests are very frequently used in educational settings and successful studying before the examinations is a complex matter to deal with. In order to understand the determinants of success in exams better, we need to take into account not only emotional and motivational, but also cognitive aspects of the participants such as dysfunctional beliefs. Our aim is to present the relationship between candidates’ characteristics and distorted beliefs/schemata just before an examination. Method: The subjects of the study were 30 female and 30 male physicians who were about to take the medical specialization exam (MSE in Turkey. Dysfunctional Attitude Scale (DAS and Young Schema Questionnaire Short Form (YSQ-SF were applied to the subjects. The statistical analysis was done using the F test, Mann-Whitney, Kruskal-Wallis, chi-square test and spearman’s correlation test. Results: It was shown that some of the DAS and YSQ-SF scores were significantly higher in female gender, in the group who could not pass the exam, who had repetitive examinations, who had their first try taking an examination and who were unemployed at the time of the examination. Conclusion: Our findings indicate that candidates seeking help before MSE examination could be referred for cognitive therapy or counseling even they do not have any psychiatric diagnosis due to clinically significant cognitive distortion. Measurement and treatment of cognitive distortions that have negative impact on MSE performance may improve the cost-effectiveness and mental well being of the young doctors.
"A regression error specification test (RESET) for generalized linear models".
Sunil Sapra
2005-01-01
Generalized linear models (GLMs) are generalizations of linear regression models, which allow fitting regression models to response data that follow a general exponential family. GLMs are used widely in social sciences for fitting regression models to count data, qualitative response data and duration data. While a variety of specification tests have been developed for the linear regression model and are routinely applied for testing for misspecification of functional form, omitted variables,...
Gravitation experiments at Stanford. [using general relativity theory
Lipa, J. A.
1980-01-01
The experimental situation in post-Newtonian gravitation is briefly reviewed in order to reexamine the extent to which experiment supports or refutes general relativity. A description is given of the equivalence principle project, the gyroscope experiment, and the search for gravity waves. It is noted that even though some doubt has been cast on the value of the perihelion advance and the gravitational redshift as precise tests of general relativity in the past few years, many competing theories have been ruled out; in particular, the results from the Viking mission significantly reduce the credibility of the Brans-Dicke theory (Brans and Dicke, 1961). The dimensionless constant omega in this theory is now forced to exceed 50, while the value originally proposed was 6 (omega being infinity in general relativity). It is noted that the gyro experiment described is capable of putting much tighter limits on this parameter, and together with the other experiments in progress will help place gravitational theory on a firmer experimental footing.
Fundamental optimal relation of a generalized irreversible Carnot ...
Indian Academy of Sciences (India)
Abstract. The fundamental optimal relation between heating load and coefficient of performance (COP) of a generalized irreversible Carnot heat pump is derived based on a new generalized heat transfer law, which includes the generalized convective heat transfer law and generalized radiative heat transfer law, ...
BOOK REVIEW: Advanced Mechanics and General Relativity Advanced Mechanics and General Relativity
Louko, Jorma
2011-04-01
Joel Franklin's textbook `Advanced Mechanics and General Relativity' comprises two partially overlapping, partially complementary introductory paths into general relativity at advanced undergraduate level. Path I starts with the Lagrangian and Hamiltonian formulations of Newtonian point particle motion, emphasising the action principle and the connection between symmetries and conservation laws. The concepts are then adapted to point particle motion in Minkowski space, introducing Lorentz transformations as symmetries of the action. There follows a focused development of tensor calculus, parallel transport and curvature, using examples from Newtonian mechanics and special relativity, culminating in the field equations of general relativity. The Schwarzschild solution is analysed, including a detailed discussion of the tidal forces on a radially infalling observer. Basics of gravitational radiation are examined, highlighting the similarities to and differences from electromagnetic radiation. The final topics in Path I are equatorial geodesics in Kerr and the motion of a relativistic string in Minkowski space. Path II starts by introducing scalar field theory on Minkowski space as a limit of point masses connected by springs, emphasising the action principle, conservation laws and the energy-momentum tensor. The action principle for electromagnetism is introduced, and the coupling of electromagnetism to a complex scalar field is developed in a detailed and pedagogical fashion. A free symmetric second-rank tensor field on Minkowski space is introduced, and the action principle of general relativity is recovered from coupling the second-rank tensor to its own energy-momentum tensor. Path II then merges with Path I and, supplanted with judicious early selections from Path I, can proceed to the Schwarzschild solution. The choice of material in each path is logical and focused. A notable example in Path I is that Lorentz transformations in Minkowki space are introduced
Derivation of Einstein-Cartan theory from general relativity
Petti, Richard J
2013-01-01
General relativity cannot describe exchange of intrinsic and orbital angular momentum. In 1922 E. Cartan proposed extending general relativity by including affine torsion, which resolves this problem. In 1986 the author published a derivation of Einstein Cartan theory from general relativity with classical spin, with no additional assumptions. This paper summarizes the derivation and adds simpler explanations of the derivation and correction of a factor of 2.
The Two-Dimensional Analogue of General Relativity
Lemos, José P. S.; Sá, Paulo M.
1993-01-01
General Relativity in three or more dimensions can be obtained by taking the limit $\\omega\\rightarrow\\infty$ in the Brans-Dicke theory. In two dimensions General Relativity is an unacceptable theory. We show that the two-dimensional closest analogue of General Relativity is a theory that also arises in the limit $\\omega\\rightarrow\\infty$ of the two-dimensional Brans-Dicke theory.
Physical constraints on causality-violating spacetimes in general relativity
Janca, Andrew Joseph
The theoretical possibility of global causality violation has long been a problem within general relativity, for there exists a large number of model spacetimes known to admit closed time-like curves, trajectories allowing a timelike observer to return to some point in her own past. However, nearly all such known models have some unphysical feature. These physicality issues rendered causality-violation to the status of an interesting but safely theoretical problem until twenty years ago, when the appearance of a new type of causality-violating model spacetime and the subsequent proliferation of new models admitting closed timelike curves forced the attention of the community to the issue, and made causality violation and its possible physical consequences an active area of research within general relativity. This paper focuses on some of the older causality-violating spacetimes which model matter sources with cylindrical symmetry. By describing how cylindrically-symmetric solutions can be embedded within a spatially bounded and physically realistic body which outwardly has the symmetry of a torus or ring, it is shown that the chief problem of physical plausibility which these older solutions possess can be resolved. The intention is to make these models active candidates for consideration in future experiments to test general relativity's prediction that causality violation is a phenomenon that could be observed in the real world. Attending chapters describe physical systems other than rotating objects that can alter a local observer's experience of time to a substantial extent, including an electrically-charged massive shell slowing time in its interior (though not affecting causality) and a class of trajectories in the Reissner-Nordstrom background that could in principle allow a timelike observer to reverse her personal arrow of time relative to other observers in the spacetime as a whole. The paper concludes with a discussion of one of the plausibility problems
Matzel, Louis D.; Grossman, Henya; Light, Kenneth; Townsend, David; Kolata, Stefan
2008-01-01
A defining characteristic of age-related cognitive decline is a deficit in general cognitive performance. Here we use a testing and analysis regimen that allows us to characterize the general learning abilities of young (3-5 mo old) and aged (19-21 mo old) male and female Balb/C mice. Animals' performance was assessed on a battery of seven diverse…
Quality of routine spirometry tests in Dutch general practices
Schermer, Tjard RJ; Crockett, Alan J; Poels, Patrick JP; van Dijke, Jacob J; Akkermans, Reinier P; Vlek, Hans F; Pieters, Willem R
2009-01-01
Background Spirometry is an indispensable tool for diagnosis and monitoring of chronic airways disease in primary care. Aim To establish the quality of routine spirometry tests in general practice, and explore associations between test quality and patient characteristics. Design of study Analysis of routine spirometry test records. Setting Fifteen general practices which had a working agreement with a local hospital pulmonary function laboratory for spirometry assessment regarding test quality and interpretation. Method Spirometry tests were judged by a pulmonary function technician and a chest physician. Proportions of test adequacy were analysed using markers for manoeuvre acceptability and test reproducibility derived from the 1994 American Thoracic Society spirometry guideline. Associations between quality markers and age, sex, and severity of obstruction were examined using logistic regression. Results Practices performed a mean of four (standard deviation = 2) spirometry tests per week; 1271 tests from 1091 adult patients were analysed; 96.4% (95% confidence interval [CI] = 95.6 to 97.2) of all tests consisted of ≥3 blows. With 60.6% of tests, forced expiratory time was the marker with the lowest acceptability rate. An overall 38.8% (95% CI = 36.0 to 41.6) of the tests met the acceptability as well as reproducibility criteria. Age, sex, and severity of obstruction were associated with test quality markers. Conclusion The quality of routine spirometry tests was better than in previous reports from primary care research settings, but there is still substantial room for improvement. Sufficient duration of forced expiratory time is the quality marker with the highest rate of inadequacy. Primary care professionals should be aware of patient characteristics that may diminish the quality of their spirometry tests. Further research is needed to establish to what extent spirometry tests that are inadequate, according to stringent international expert criteria
Quality of routine spirometry tests in Dutch general practices.
Schermer, T.R.J.; Crockett, A.J.; Poels, P.J.P.; Dijke, J.J. van; Akkermans, R.P.; Vlek, H.F.; Pieters, W.R.
2009-01-01
BACKGROUND: Spirometry is an indispensable tool for diagnosis and monitoring of chronic airways disease in primary care. AIM: To establish the quality of routine spirometry tests in general practice, and explore associations between test quality and patient characteristics. DESIGN OF STUDY: Analysis
40 CFR 86.151-98 - General requirements; refueling test.
2010-07-01
... vehicle shall be approximately level during all phases of the test sequence to prevent abnormal fuel... 40 Protection of Environment 18 2010-07-01 2010-07-01 false General requirements; refueling test... Regulations for 1977 and Later Model Year New Light-Duty Vehicles and New Light-Duty Trucks and New Otto-Cycle...
Fixing extensions to general relativity in the nonlinear regime
Cayuso, Juan; Ortiz, Néstor; Lehner, Luis
2017-10-01
The question of what gravitational theory could supersede General Relativity has been central in theoretical physics for decades. Many disparate alternatives have been proposed motivated by cosmology, quantum gravity and phenomenological angles, and have been subjected to tests derived from cosmological, solar system and pulsar observations typically restricted to linearized regimes. Gravitational waves from compact binaries provide new opportunities to probe these theories in the strongly gravitating/highly dynamical regimes. To this end however, a reliable understanding of the dynamics in such a regime is required. Unfortunately, most of these theories fail to define well posed initial value problems, which prevents at face value from meeting such challenge. In this work, we introduce a consistent program able to remedy this situation. This program is inspired in the approach to "fixing" viscous relativistic hydrodynamics introduced by Israel and Stewart in the late 70's. We illustrate how to implement this approach to control undesirable effects of higher order derivatives in gravity theories and argue how the modified system still captures the true dynamics of the putative underlying theories in 3 +1 dimensions. We sketch the implementation of this idea in a couple of effective theories of gravity, one in the context of Noncommutative Geometry, and one in the context of Chern-Simons modified General Relativity.
Parathyroid hormone-related protein blood test
... ency/article/003691.htm Parathyroid hormone-related protein blood test To use the sharing features on this page, ... measures the level of a hormone in the blood, called parathyroid hormone-related protein. How the Test is Performed A blood sample is needed . How ...
Differential forms and the geometry of general relativity
Dray, Tevian
2015-01-01
Differential Forms and the Geometry of General Relativity provides readers with a coherent path to understanding relativity. Requiring little more than calculus and some linear algebra, it helps readers learn just enough differential geometry to grasp the basics of general relativity.The book contains two intertwined but distinct halves. Designed for advanced undergraduate or beginning graduate students in mathematics or physics, most of the text requires little more than familiarity with calculus and linear algebra. The first half presents an introduction to general relativity that describes
Motivations for anti-gravity in general relativity
Energy Technology Data Exchange (ETDEWEB)
Chardin, G. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee
1996-05-01
Arguments are presented showing that it is natural to interpret the negative mass part of the Kerr solution as representing the geometry experienced by antimatter. The C, P and T discrete transformations are considered for this geometry. The C and T properties of the proposed identification are found to be in agreement with the usual representation of antimatter. In addition, a property of perfect stigmatism through Kerr wormholes which allows general relativity to mimic anti-gravity is conjectured. Kerr wormholes would then act as `super-mirrors` reversing the C, P and T images of an object seen through it. This interpretation is subjected to several experimental tests and able to provide an explanation, without any free parameter, of the `CP`-violation observed in the neutral kaon system. (K.A.). 37 refs.
Probing strong-field general relativity near black holes
CERN. Geneva; Alvarez-Gaumé, Luís
2005-01-01
Nature has sprinkled black holes of various sizes throughout the universe, from stellar mass black holes in X-ray sources to supermassive black holes of billions of solar masses in quasars. Astronomers today are probing the spacetime near black holes using X-rays, and gravitational waves will open a different view in the near future. These tools give us an unprecedented opportunity to test ultra-strong-field general relativity, including the fundamental theorem of the uniqueness of the Kerr metric and Roger Penrose's cosmic censorship conjecture. Already, fascinating studies of spectral lines are showing the extreme gravitational lensing effects near black holes and allowing crude measurements of black hole spin. When the ESA-NASA gravitational wave detector LISA begins its observations in about 10 years, it will make measurements of dynamical spacetimes near black holes with an accuracy greater even than that which theoreticians can reach with their computations today. Most importantly, when gravitational wa...
General scaling relations for locomotion in granular media
Slonaker, James; Motley, D. Carrington; Zhang, Qiong; Townsend, Stephen; Senatore, Carmine; Iagnemma, Karl; Kamrin, Ken
2017-05-01
Inspired by dynamic similarity in fluid systems, we have derived a general dimensionless form for locomotion in granular materials, which is validated in experiments and discrete element method (DEM) simulations. The form instructs how to scale size, mass, and driving parameters in order to relate dynamic behaviors of different locomotors in the same granular media. The scaling can be derived by assuming intrusion forces arise from resistive force theory or equivalently by assuming the granular material behaves as a continuum obeying a frictional yield criterion. The scalings are experimentally confirmed using pairs of wheels of various shapes and sizes under many driving conditions in a common sand bed. We discuss why the two models provide such a robust set of scaling laws even though they neglect a number of the complexities of granular rheology. Motivated by potential extraplanetary applications, the dimensionless form also implies a way to predict wheel performance in one ambient gravity based on tests in a different ambient gravity. We confirm this using DEM simulations, which show that scaling relations are satisfied over an array of driving modes even when gravity differs between scaled tests.
Test-taking anxiety among nursing & general college students.
Brewer, Thomas
2002-11-01
This study examined whether nursing students experience an unusual amount of debilitative anxiety in academic achievement, compared to general university students and provided senior psychiatric nursing students with a hands-on experience in research. A nonprobability convenience sample of 225 students was drawn from a university in the eastern United States. Alpert and Haber's Achievement Anxiety Test was administered to 94 nursing students and 131 general university students. Results indicated that nursing students do not have a statistically significantly higher debilitative anxiety than the general student population. However, all students experienced significantly higher levels of debilitative anxiety than were found by Alpert and Haber. Implications for academic nursing are discussed.
Einstein's general theory of relativity with modern applications in cosmology
Grøn, Øyvind
2007-01-01
Many of us have experienced the same; fallen and broken something. Yet supposedly, gravity is the weakest of the fundamental forces; it is claimed to be 10-15 times weaker than electromagnetism. Still, every one of us has more or less had a personal relationship with gravity. Einstein’s General Theory of Relativity: With Modern Applications in Cosmology by Oyvind Gron and Sigbjorn Hervik is about gravity and the concept of gravity as Albert Einstein saw it- curved spaces, four-dimensional manifolds and geodesics. The book starts with the 1st principals of relativity and an introduction to Einstein’s field equations. Next up are the three classical tests of the relativity theory and an introduction to black holes. The book contains several topics not found in other textbooks, such as Kaluza-Klein theory, anisotropic models of the universe, and new developments involving brane cosmology. Gron and Hervik have included a part in the book called "Advanced Topics." These topics range from the very edge of resea...
6th International Conference on the History of General Relativity
Eisenstaedt, Jean; The Universe of General Relativity; GR 6
2005-01-01
This volume from the Einstein Studies Series is based largely on papers presented at the Sixth International Conference on the History of General Relativity, held in Amsterdam on June 26-29, 2002. These contributions from notable experts offer both new and historical insights on gravitation, general relativity, cosmology, unified field theory, and the history of science. Topics discussed include the prehistory of special relativity, early attempts at a relativistic theory of gravitation, the beginnings of general relativity, the problem of motion in the context of relativity, conservation laws, the axiomatization of relativity, classical and contemporary cosmology, gravitation and electromagnetism, quantum gravity, and relativity as seen through the eyes of the public and renowned relativists. Contributors: K. Brading; G. Gale; H.F.M. Goenner; J. Goldberg; S. Katzir; D. Kennefick; H. Kragh; C. Lehner; U. Majer; J. Mattingly; E.T. Newman; J.D. Norton; J. Renn; R. Rynasiewicz; J.M. Sánchez-Ron; T. Sauer; C. Sm...
Poisson, Eric
2010-05-01
chapter 11 the student is introduced to black holes. A large part of the chapter is devoted to the study of geodesic motion in Schwarzschild spacetime, and this allows Schutz to make contact with the classical tests of general relativity: perihelion advance and light deflection. The singular behaviour of the Schwarzschild coordinates at the event horizon is described in detail. This reveals another weakness of the book: the Kruskal coordinates are simply written down, with no derivation and little motivation; it is a pity that Schutz did not choose to introduce the Eddington--Finkelstein coordinates, or the Painlevé-Gullstand coordinates, as easier alternatives. The chapter ends with a general discussion of black holes (including their place in astrophysics and a description of the Hawking effect) and a detailed presentation of the Kerr solution. The last chapter (chapter 12) is devoted to cosmology, and this is the part of the book that was the most thoroughly revised. The presentation begins with the enunciation of the cosmological principle and a derivation of the Friedmann-Lemaitre models. It continues with a discussion of cosmological dynamics in the presence of pressureless matter, radiation, and a cosmological constant (of which nobody wanted to be reminded at the time of the first edition). It concludes with an up-to-date review of cosmological measurements and a (very) brief history of the Universe, from the big bang to inflation, to recombination, to structure formation. The presentation of general relativity and its applications contained in this book is suitable for undergraduate students who would prefer the standard `math-first approach' to Hartle's `physics-first approach'. The student will learn the essentials of differential geometry in a gentle way, and will then apply these tools to physics in curved spacetime; all of this can be accomplished in a brisk one-semester course. The book leaves out many topics than can be found in more advanced texts, such
Input Range Testing for the General Mission Analysis Tool (GMAT)
Hughes, Steven P.
2007-01-01
This document contains a test plan for testing input values to the General Mission Analysis Tool (GMAT). The plan includes four primary types of information, which rigorously define all tests that should be performed to validate that GMAT will accept allowable inputs and deny disallowed inputs. The first is a complete list of all allowed object fields in GMAT. The second type of information, is test input to be attempted for each field. The third type of information is allowable input values for all objects fields in GMAT. The final piece of information is how GMAT should respond to both valid and invalid information. It is VERY important to note that the tests below must be performed for both the Graphical User Interface and the script!! The examples are illustrated using a scripting perspective, because it is simpler to write up. However, the test must be performed for both interfaces to GMAT.
General Theory of Relativity-The Power of Speculative Thought
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 4. General Theory of Relativity – The Power of Speculative Thought. Asit Banerjee. General Article Volume 11 Issue 4 April 2006 pp 45-55. Fulltext. Click here to view fulltext PDF. Permanent link:
Understanding General Relativity after 100 years: A matter of perspective
Dadhich, Naresh
2016-01-01
This is the centenary year of general relativity, it is therefore natural to reflect on what perspective we have evolved in 100 years. I wish to share here a novel perspective, and the insights and directions that ensue from it.
General and special education teachers' relations within teamwork ...
African Journals Online (AJOL)
General and special education teachers' relations within teamwork in inclusive education: socio-demographic characteristics. M Radiæ-Šestic, V Radovanovic, B Milanovic-Dobrota, S Slavkovic, A Langoviæ-Milicvic ...
Relations between task delegation and job satisfaction in general practice
DEFF Research Database (Denmark)
Riisgaard, Helle; Nexøe, Jørgen; Videbæk Le, Jette
2016-01-01
BACKGROUND: It has for years been discussed whether practice staff should be involved in patient care in general practice to a higher extent. The research concerning task delegation within general practice is generally increasing, but the literature focusing on its influence on general practition......BACKGROUND: It has for years been discussed whether practice staff should be involved in patient care in general practice to a higher extent. The research concerning task delegation within general practice is generally increasing, but the literature focusing on its influence on general...... task delegation and general practitioners' and their staff's job satisfaction and, additionally, 2) to review the evidence of possible explanations for this relation. METHODS: A systematic literature review. We searched the four databases PubMed, Cinahl, Embase, and Scopus systematically. The immediate....... They explored views and attitudes of the staff, encompassing nurses as well as practice managers. Only one of the included studies also explored general practitioners' views and attitudes, hence making it impossible to establish any syntheses on this relation. According to the studies, the staff's overall...
40 CFR 1065.701 - General requirements for test fuels.
2010-07-01
... 40 Protection of Environment 32 2010-07-01 2010-07-01 false General requirements for test fuels. 1065.701 Section 1065.701 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... procedure 1 Light distillate and light blends with residual ASTM D975-07b. Diesel Middle distillate ASTM...
Generalized Correlation Coefficient Based on Log Likelihood Ratio Test Statistic
Directory of Open Access Journals (Sweden)
Liu Hsiang-Chuan
2016-01-01
Full Text Available In this paper, I point out that both Joe’s and Ding’s strength statistics can only be used for testing the pair-wise independence, and I propose a novel G-square based strength statistic, called Liu’s generalized correlation coefficient, it can be used to detect and compare the strength of not only the pair-wise independence but also the mutual independence of any multivariate variables. Furthermore, I proved that only Liu’s generalized correlation coefficient is strictly increasing on its number of variables, it is more sensitive and useful than Cramer’s V coefficient, in other words, Liu generalized correlation coefficient is not only the G-square based strength statistic, but also an improved statistic for detecting and comparing the strengths of deferent associations of any two or more sets of multivariate variables, moreover, this new strength statistic can also be tested by G2.
A generalized association test based on U statistics.
Wei, Changshuai; Lu, Qing
2017-07-01
Second generation sequencing technologies are being increasingly used for genetic association studies, where the main research interest is to identify sets of genetic variants that contribute to various phenotypes. The phenotype can be univariate disease status, multivariate responses and even high-dimensional outcomes. Considering the genotype and phenotype as two complex objects, this also poses a general statistical problem of testing association between complex objects. We here proposed a similarity-based test, generalized similarity U (GSU), that can test the association between complex objects. We first studied the theoretical properties of the test in a general setting and then focused on the application of the test to sequencing association studies. Based on theoretical analysis, we proposed to use Laplacian Kernel-based similarity for GSU to boost power and enhance robustness. Through simulation, we found that GSU did have advantages over existing methods in terms of power and robustness. We further performed a whole genome sequencing (WGS) scan for Alzherimer's disease neuroimaging initiative data, identifying three genes, APOE , APOC1 and TOMM40 , associated with imaging phenotype. We developed a C ++ package for analysis of WGS data using GSU. The source codes can be downloaded at https://github.com/changshuaiwei/gsu . weichangshuai@gmail.com ; qlu@epi.msu.edu. Supplementary data are available at Bioinformatics online.
Thurstonian models for sensory discrimination tests as generalized linear models
DEFF Research Database (Denmark)
Brockhoff, Per B.; Christensen, Rune Haubo Bojesen
2010-01-01
Sensory discrimination tests such as the triangle, duo-trio, 2-AFC and 3-AFC tests produce binary data and the Thurstonian decision rule links the underlying sensory difference 6 to the observed number of correct responses. In this paper it is shown how each of these four situations can be viewed...... as a so-called generalized linear model. The underlying sensory difference 6 becomes directly a parameter of the statistical model and the estimate d' and it's standard error becomes the "usual" output of the statistical analysis. The d' for the monadic A-NOT A method is shown to appear as a standard...... linear contrast in a generalized linear model using the probit link function. All methods developed in the paper are implemented in our free R-package sensR (http://www.cran.r-project.org/package=sensR/). This includes the basic power and sample size calculations for these four discrimination tests...
Implications of a positive cosmological constant for general relativity
Ashtekar, Abhay
2017-10-01
Most of the literature on general relativity over the last century assumes that the cosmological constant Λ is zero. However, by now independent observations have led to a consensus that the dynamics of the universe is best described by Einstein’s equations with a small but positive Λ . Interestingly, this requires a drastic revision of conceptual frameworks commonly used in general relativity, no matter how small Λ is. We first explain why, and then summarize the current status of generalizations of these frameworks to include a positive Λ , focusing on gravitational waves.
Implications of a positive cosmological constant for general relativity.
Ashtekar, Abhay
2017-10-01
Most of the literature on general relativity over the last century assumes that the cosmological constant [Formula: see text] is zero. However, by now independent observations have led to a consensus that the dynamics of the universe is best described by Einstein's equations with a small but positive [Formula: see text]. Interestingly, this requires a drastic revision of conceptual frameworks commonly used in general relativity, no matter how small [Formula: see text] is. We first explain why, and then summarize the current status of generalizations of these frameworks to include a positive [Formula: see text], focusing on gravitational waves.
The general class of the vacuum spherically symmetric equations of the general relativity theory
Energy Technology Data Exchange (ETDEWEB)
Karbanovski, V. V., E-mail: Karbanovski_V_V@mail.ru; Sorokin, O. M.; Nesterova, M. I.; Bolotnyaya, V. A.; Markov, V. N., E-mail: Markov_Victor@mail.ru; Kairov, T. V.; Lyash, A. A.; Tarasyuk, O. R. [Murmansk State Pedagogical University (Russian Federation)
2012-08-15
The system of the spherical-symmetric vacuum equations of the General Relativity Theory is considered. The general solution to a problem representing two classes of line elements with arbitrary functions g{sub 00} and g{sub 22} is obtained. The properties of the found solutions are analyzed.
The general theory of relativity a mathematical exposition
Das, Anadijiban
2012-01-01
The General Theory of Relativity: A Mathematical Exposition will serve readers as a modern mathematical introduction to the general theory of relativity. Throughout the book, examples, worked-out problems, and exercises (with hints and solutions) are furnished. Topics in this book include, but are not limited to: • tensor analysis • the special theory of relativity • the general theory of relativity and Einstein’s field equations • spherically symmetric solutions and experimental confirmations • static and stationary space-time domains • black holes • cosmological models • algebraic classifications and the Newman-Penrose equations • the coupled Einstein-Maxwell-Klein-Gordon equations • appendices covering mathematical supplements and special topics Mathematical rigor, yet very clear presentation of the topics make this book a unique text for both university students and research scholars. Anadijiban Das has taught courses on Relativity Theory at The University College of Dublin, Irelan...
Acceptance of genetic testing in a general population
DEFF Research Database (Denmark)
Aro, A R; Hakonen, A; Hietala, M
1997-01-01
The aim of the study was to analyze effects of age, education and gender on acceptance of genetic testing. Subjects, n = 1967 aged 15-69, were a stratified random sample of the Finnish population. One thousand, one hundred and sixty nine subjects, 530 men and 639 women, returned the questionnaire....... The majority of the respondents approved of the availability of genetic testing. Young, aged 15-24, were more favourable towards testing and more willing to undergo suggested tests, but they were also more worried than others about the misuse of test results. Men aged 45-69 with only basic education were more...... in favour of mandatory genetic testing than other respondents. Respondents with university education were more critical towards genetic testing and expressed their worry about eugenics more often than other education groups. In conclusion, there are age, education and gender related differences...
Maximilien Brice
2011-01-01
8 April 2011 - Brazilian Minister of State for Science and Technology A. Mercadante Oliva signing the guest book with CERN Director-General R. Heuer and Head of International Relations F. Pauss; in the ATLAS visitor centre with Collaboration Former Spokesperson P. Jenni; visiting LHC superconducting magnet test hall with J.M. Jimenez.
Maximilien brice
2011-01-01
1 April 2011 - Croatian Rudjer Boskovic Institute (RBI)Director-General D. Ramljak visiting CMS Control Centre in Meyrin with Collaboration Spokesperson G. Tonelli; signing the guest book with Head of International Relations F. Pauss and visiting LHC superconducting magnet test hall with L. Walckiers.
Relative Entropy and Variational Properties of Generalized Gibbsian Measures
Külske, Christof; Ny, Arnaud Le; Redig, Frank
2004-01-01
We study the relative entropy density for generalized Gibbs measures. We first show its existence and obtain a familiar expression in terms of entropy and relative energy for a class of “almost Gibbsian measures” (almost sure continuity of conditional probabilities). For quasilocal measures, we
Probing General Relativity and New Physics with Lunar Laser Ranging
Energy Technology Data Exchange (ETDEWEB)
Dell' Agnello, S. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Maiello, M., E-mail: mauro.maiello@lnf.infn.it [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Currie, D.G. [University of Maryland (UMD), College Park, MD (United States); Boni, A.; Berardi, S.; Cantone, C.; Delle Monache, G.O.; Intaglietta, N.; Lops, C.; Garattini, M.; Martini, M.; Patrizi, G.; Porcelli, L.; Tibuzzi, M. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Vittori, R. [Aeronautica Militare Italiana (AMI), Rome (Italy); Agenzia Spaziale Italiana (ASI), Rome (Italy); Bianco, G. [ASI-Centro di Geodesia Spaziale, Matera (Italy); Coradini, A. [INAF-Istituto di Fisica dello Spazio Interplanetario (IFSI), Via Fosso del Cavaliere 100, 00133 Rome (Italy); Dionisio, C. [Rheinmetall Italia S.p.A., Via Affile 102, 00131 Rome (Italy); March, R. [INFN-LNF and CNR-Istituto per le Applicazioni del Calcolo (IAC), Viale del Policlinico 137, 00161 Rome (Italy); Bellettini, G. [INFN-LNF and Department of Mathematics, University of Rome ' Tor Vergata' , Via della Ricerca Scientifica, 00133 Rome (Italy); and others
2012-11-11
Over the past 40 years, Lunar Laser Ranging (LLR, developed by the Univ. of Maryland (PI) and INFN-LNF (Co-PI)) to the Apollo Cube Corner Retroreflector (CCR) arrays have supplied almost all the significant tests of General Relativity (Currie et al., 2009 [12]). LLR can evaluate the PPN (Post Newtonian Parameters), addressing this way both the possible changes in the gravitational constant and the self-energy properties of the gravitational field. In addition, the LLR has provided significant information on the composition and origin of the Moon. This is the only Apollo experiment that is still in operation. Initially the Apollo LLR arrays contributed a negligible fraction of the ranging error budget. Over the decades, the ranging capabilities of the ground stations have improved by more than two orders of magnitude. Now, because of the lunar librations, the existing Apollo retroreflector arrays contribute a significant fraction of the limiting errors in the range measurements. We built a new experimental apparatus (the 'Satellite/Lunar Laser Ranging Characterization Facility', SCF) and created a new test procedure (the SCF-Test) to characterize and model the detailed thermal behavior and the optical performance of cube corner laser retroreflectors in space for industrial and scientific applications (Dell'Agnello et al., 2011 [13]). Our key experimental innovation is the concurrent measurement and modeling of the optical Far Field Diffraction Pattern (FFDP) and the temperature distribution of the SLR retroreflector payload under thermal conditions produced with a close-match solar simulator. The apparatus includes infrared cameras for non-invasive thermometry, thermal control and real-time movement of the payload to experimentally simulate satellite orientation on orbit with respect to both solar illumination and laser interrogation beams. These unique capabilities provide experimental validation of the space segment for SLR and Lunar Laser Ranging
Probing General Relativity and New Physics with Lunar Laser Ranging
Dell'Agnello, S.; Maiello, M.; Currie, D. G.; Boni, A.; Berardi, S.; Cantone, C.; Delle Monache, G. O.; Intaglietta, N.; Lops, C.; Garattini, M.; Martini, M.; Patrizi, G.; Porcelli, L.; Tibuzzi, M.; Vittori, R.; Bianco, G.; Coradini, A.; Dionisio, C.; March, R.; Bellettini, G.; Tauraso, R.; Chandler, J.
2012-11-01
Over the past 40 years, Lunar Laser Ranging (LLR, developed by the Univ. of Maryland (PI) and INFN-LNF (Co-PI)) to the Apollo Cube Corner Retroreflector (CCR) arrays have supplied almost all the significant tests of General Relativity (Currie et al., 2009 [12]). LLR can evaluate the PPN (Post Newtonian Parameters), addressing this way both the possible changes in the gravitational constant and the self-energy properties of the gravitational field. In addition, the LLR has provided significant information on the composition and origin of the Moon. This is the only Apollo experiment that is still in operation. Initially the Apollo LLR arrays contributed a negligible fraction of the ranging error budget. Over the decades, the ranging capabilities of the ground stations have improved by more than two orders of magnitude. Now, because of the lunar librations, the existing Apollo retroreflector arrays contribute a significant fraction of the limiting errors in the range measurements. We built a new experimental apparatus (the ‘Satellite/Lunar Laser Ranging Characterization Facility', SCF) and created a new test procedure (the SCF-Test) to characterize and model the detailed thermal behavior and the optical performance of cube corner laser retroreflectors in space for industrial and scientific applications (Dell'Agnello et al., 2011 [13]). Our key experimental innovation is the concurrent measurement and modeling of the optical Far Field Diffraction Pattern (FFDP) and the temperature distribution of the SLR retroreflector payload under thermal conditions produced with a close-match solar simulator. The apparatus includes infrared cameras for non-invasive thermometry, thermal control and real-time movement of the payload to experimentally simulate satellite orientation on orbit with respect to both solar illumination and laser interrogation beams. These unique capabilities provide experimental validation of the space segment for SLR and Lunar Laser Ranging (LLR). The
A remark on generalized commutation relation and subnormality
Directory of Open Access Journals (Sweden)
Jerzy Bartłomiej Stochel
2006-01-01
Full Text Available Tillmann [Tillmann H. G., Zur Eindeutigkeit der Losungen der quanten mechanischen vertauschungrelationen, Acta Sci. Math. (Szeged 24 (1963, 258-270] proved that every operator \\(A\\ which fulfils the canonical commutation relation \\(A^{*}A - AA^{*} = Id\\ is an orthogonal sum of canonical creation operators. We extend this result for operators which fulfil generalized commutation relation \\[A^{*}A - AA^{*}= E^2,\\text{ where }EA = AE.\\] In addition, some inequalities which are helpful in describing analytic vectors of operators \\(A^{*}A\\, where \\(A\\ fulfils the generalized commutation relation, are established.
A crosscultural validation of a test of science related attitudes
Khalili, Khalil Y.
A test for measuring science attitudes, named Test of Science Related Attitudes (TOSRA), was initially developed in Australia by Fraser (1977, 1978). This study investigated the crosscultural validity of this instrument when used with American high school students. Three hundred and thirty-six students (12th and 11th graders) in three high schools in suburban Chicago took the test. The results of the study, confirming previous validation of the test, revealed that the seven subscales of TOSRA were, in general, highly reliable. The discriminant validity of each of these scales, however, was found to be generally low. The item/scale correlation for all but four items of the test met Shrigley's (Journal of Research in Science Teaching, 20(1), 87-89, 1983) criterion of being more than 0.30. The results of the principal components with varimax rotation did not support the distinctiveness of the subscale structure of the test.
Energy Technology Data Exchange (ETDEWEB)
Iorio, Lorenzo [Ministero dell' Istruzione Univ. della Ricerca (M.I.U.R.), Bari (Italy)
2017-02-15
Recently, Ciufolini et al. reported on a test of the general relativistic gravitomagnetic Lense-Thirring effect by analyzing about 3.5 years of laser ranging data to the LAGEOS, LAGEOS II, LARES geodetic satellites orbiting the Earth. By using the GRACE-based GGM05S Earth's global gravity model and a linear combination of the nodes Ω of the three satellites designed to remove the impact of errors in the first two even zonal harmonic coefficients J{sub 2}, J{sub 4} of the multipolar expansion of the Newtonian part of the Earth's gravitational potential, they claimed an overall accuracy of 5% for the Lense-Thirring caused node motion. We show that the scatter in the nominal values of the uncancelled even zonals of degree l = 6, 8, 10 from some of the most recent global gravity models does not yet allow to reach unambiguously and univocally the expected ∼1% level, being large up to
Hydrodynamics in full general relativity with conservative adaptive mesh refinement
East, William E.; Pretorius, Frans; Stephens, Branson C.
2012-06-01
There is great interest in numerical relativity simulations involving matter due to the likelihood that binary compact objects involving neutron stars will be detected by gravitational wave observatories in the coming years, as well as to the possibility that binary compact object mergers could explain short-duration gamma-ray bursts. We present a code designed for simulations of hydrodynamics coupled to the Einstein field equations targeted toward such applications. This code has recently been used to study eccentric mergers of black hole-neutron star binaries. We evolve the fluid conservatively using high-resolution shock-capturing methods, while the field equations are solved in the generalized-harmonic formulation with finite differences. In order to resolve the various scales that may arise, we use adaptive mesh refinement (AMR) with grid hierarchies based on truncation error estimates. A noteworthy feature of this code is the implementation of the flux correction algorithm of Berger and Colella to ensure that the conservative nature of fluid advection is respected across AMR boundaries. We present various tests to compare the performance of different limiters and flux calculation methods, as well as to demonstrate the utility of AMR flux corrections.
The gyromagnetic factor in electrodynamics, quantum theory and general relativity
Pfister, H D
2003-01-01
Starting with some basic facts about the gyromagnetic factor g in Maxwell's theory, we review the special role played by a g factor g=2 in quantum mechanics and elementary particle physics, and we draw attention to the same value g=2 for the black holes and many other (electro-)vacuum solutions of general relativity. We strengthen and extend this special role of g=2 in general relativity by considering a class of slowly rotating, charged mass shells, showing that the black-hole value g=2 is extremely robust. Therefrom, we advance the hypothesis that the coincidence between these preferred g values signifies a deep common root of quantum theory and general relativity.
Introduction to general relativity, black holes and cosmology
Choquet-Bruhat, Yvonne
2015-01-01
General Relativity is a beautiful geometric theory, simple in its mathematical formulation but leading to numerous consequences with striking physical interpretations: gravitational waves, black holes, cosmological models, and so on. This introductory textbook is written for mathematics students interested in physics and physics students interested in exact mathematical formulations (or for anyone with a scientific mind who is curious to know more of the world we live in), recent remarkable experimental and observational results which confirm the theory are clearly described and no specialised physics knowledge is required. The mathematical level of Part A is aimed at undergraduate students and could be the basis for a course on General Relativity. Part B is more advanced, but still does not require sophisticated mathematics. Based on Yvonne Choquet-Bruhat's more advanced text, General Relativity and the Einstein Equations, the aim of this book is to give with precision, but as simply as possible, the found...
New Superpotential in Conservation Laws in General Relativity
Adamek, J
2016-01-01
This work refers to the new formula for the superpotential Uikl in conservation laws in general relativity satisfying the integral and differential conservation laws within the Schwarzschild metric. The new superpotential is composed of two terms. The first term is based on Mollers concept and its a function of the metric gik and its first derivative only. The second term is the antisymmetric tensor density of weight plus one and it consists of higher derivatives of the metric gik. Although the new superpotential consists of higher derivatives of the metric gik it might bring a new evaluation of the conservative quantities in general relativity
Essays in general relativity a Festschrift for Abraham Taub
Tipler, Frank J
1981-01-01
Essays in General Relativity: A Festschrift for Abraham Taub is collection of essays to honor Professor Abraham H. Taub on the occasion of his retirement from the mathematics faculty of the University of California at Berkeley. Relativistic hydrodynamics has always been a subject dear to Taub's heart. In fact, many basic results on special relativistic fluid flows are due to him, and he has been a major contributor to the study of fluid flows near shocks. The book contains 16 chapters and begins with a discussion of a geometrical approach to general relativity. This is followed by separate cha
On the mathematical theory of classical fields and general relativity
Klainerman, S
1993-01-01
From the perspective of an analyst, like myself, the General Theory of Relativity provides an extrordinary rich and vastly virgin territory. It is the aim of my lecture to provide, ﬁrst, an account of those aspects of the theory which attract me most and second a perspective of what has been accomplished so far in that respect. In trying to state our main objectives it helps to view General Relativity in the broader context of Classical Field Theory. EinsteiniVacuum equations, or shortly E—V, is already sufﬁciently complicated. I will thus restrict my attention to them.
Test and evaluation of the generalized gate logic system simulator
Miner, Paul S.
1991-01-01
The results of the initial testing of the Generalized Gate Level Logic Simulator (GGLOSS) are discussed. The simulator is a special purpose fault simulator designed to assist in the analysis of the effects of random hardware failures on fault tolerant digital computer systems. The testing of the simulator covers two main areas. First, the simulation results are compared with data obtained by monitoring the behavior of hardware. The circuit used for these comparisons is an incomplete microprocessor design based upon the MIL-STD-1750A Instruction Set Architecture. In the second area of testing, current simulation results are compared with experimental data obtained using precursors of the current tool. In each case, a portion of the earlier experiment is confirmed. The new results are then viewed from a different perspective in order to evaluate the usefulness of this simulation strategy.
Cancer-related false knowledge in relatives of cancer patients and the general public.
Turhal, N S; Dane, F; Ulus, C; Sari, S; Senturk, N; Bingol, D
2010-01-01
Although there are many myths about cancer in Turkey, there is no study evaluating Turkish public's knowledge about cancer. The goals of our research were to: 1) measure the extent of knowledge of cancer among the Turkish public; 2) determine the differences in extent of cancer-related knowledge between participants who have relatives with cancer and those who do not; and 3) determine the sources of knowledge possessed. Data were obtained from a total of 415 participants (244 female, 171 male), all of them sitting at the Marmara University Faculty of Medicine Hospital (MUFMH) outpatient clinic waiting area for non-cancer-related reasons. Each participant completed a 3-part questionnaire. Appropriate statistical tests were used for comparison. The mean age was 41 years. Of 415 participants, 65.3% stated that they had one or more cancer patient in their immediate family; 70.1% of the participants had a high-school education or greater. The questionnaire showed that, depending on the question, anywhere from 1.7% to 88.5% of the general public possesses some false information; furthermore, the difference in accuracy between relatives of cancer patients and non-relatives was marginal. Only 3 specific questions, related to the following ideas, rendered answers that were statistically significantly different between these 2 groups: breast cancer is only seen in females (p knowledge about cancer was unacceptably high in our cohort. Broader efforts should be made to inform the Turkish public about cancer.
Doppler frequency in interplanetary radar and general relativity
Mcvittie, G. C.
1972-01-01
The change of frequency of an interplanetary radar signal sent from the earth to another planet or to a space probe is worked out according to general relativity. The Schwarzschild spacetime is employed and its null geodesics control the motion of the signals. Exact Doppler frequency formulas are derived for one-way and two-way radar in terms of an arbitrary Schwarzschild radial coordinate. A reduction to the special relativity case is used to interpret the formulas in terms of the relative radial velocity of emitter and target. The general relativity corrections are worked out approximately for each of three possible Schwarzschild radial coordinates, and a numerical example is given. The amount of the correction is different according as one or the other of the Schwarzschild coordinates is identified with the radius vector deduced from classical celestial mechanics. The identification problem is discussed.
Arithmetic for the unification of quantum mechanics and general relativity
Energy Technology Data Exchange (ETDEWEB)
Korotkikh, Victor, E-mail: v.korotkikh@cqu.edu.a [School of Computing Sciences, Faculty of Business and Informatics, Central Queensland University, Mackay, Queensland, 4740 (Australia)
2009-06-01
In the paper we bring attention to description of complex systems in terms of self-organization processes of prime integer relations. Revealed through the unity of two equivalent forms, arithmetical and geometrical, the description may have the potential for the unification of quantum mechanics and general relativity. Remarkably, based on integers and controlled by arithmetic only such processes can define nonlocal correlations between parts of a complex system and the geometry of their spacetimes.
BOOK REVIEW: Partial Differential Equations in General Relativity
Halburd, Rodney G.
2008-11-01
Although many books on general relativity contain an overview of the relevant background material from differential geometry, very little attention is usually paid to background material from the theory of differential equations. This is understandable in a first course on relativity but it often limits the kinds of problems that can be studied rigorously. Einstein's field equations lie at the heart of general relativity. They are a system of partial differential equations (PDEs) relating the curvature of spacetime to properties of matter. A central part of most problems in general relativity is to extract information about solutions of these equations. Most standard texts achieve this by studying exact solutions or numerical and analytical approximations. In the book under review, Alan Rendall emphasises the role of rigorous qualitative methods in general relativity. There has long been a need for such a book, giving a broad overview of the relevant background from the theory of partial differential equations, and not just from differential geometry. It should be noted that the book also covers the basic theory of ordinary differential equations. Although there are many good books on the rigorous theory of PDEs, methods related to the Einstein equations deserve special attention, not only because of the complexity and importance of these equations, but because these equations do not fit into any of the standard classes of equations (elliptic, parabolic, hyperbolic) that one typically encounters in a course on PDEs. Even specifying exactly what ones means by a Cauchy problem in general relativity requires considerable care. The main problem here is that the manifold on which the solution is defined is determined by the solution itself. This means that one does not simply define data on a submanifold. Rendall's book gives a good overview of applications and results from the qualitative theory of PDEs to general relativity. It would be impossible to give detailed
Testing Asteroseismic Scaling Relations with Interferometry
Directory of Open Access Journals (Sweden)
White T. R.
2015-01-01
Full Text Available The asteroseismic scaling relations for the frequency of maximum oscillation power, vmax, and the large frequency separation, Δν, provide an easy way to directly determine the masses and radii of stars with detected solar-like oscillations. With the vast amount of data available from the CoRoT and Kepler missions, the convenience of the scaling relations has resulted in their wide-spread use. But how valid are the scaling relations when applied to red giants, which have a substantially different structure than the Sun? Verifying the scaling relations empirically requires independent measurements. We report on the current state and future prospects of interferometric tests of the scaling relations.
A general diagnostic model applied to language testing data.
von Davier, Matthias
2008-11-01
Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.
Bianchi type-V string cosmological models in general relativity
Indian Academy of Sciences (India)
Abstract. Bianchi type-V string cosmological models in general relativity are investigated. To get the exact solution of Einstein's field equations, we have taken some scale transformations used by Camci et al [Astrophys. Space Sci. 275, 391 (2001)]. It is shown that Einstein's field equations are solvable for any arbitrary ...
Bianchi type-V string cosmological models in general relativity
Indian Academy of Sciences (India)
Bianchi type-V string cosmological models in general relativity are investigated. To get the exact solution of Einstein's ﬁeld equations, we have taken some scale transformations used by Camci et al [Astrophys. Space Sci. 275, 391 (2001)]. It is shown that Einstein's ﬁeld equations are solvable for any arbitrary cosmic scale ...
Bianchi type IX string cosmological model in general relativity
Indian Academy of Sciences (India)
Abstract. We have investigated Bianchi type IX string cosmological models in general relativity. To get a determinate solution, we have assumed a condition p = λ i.e. rest energy density for a cloud of strings is equal to the string tension density. The various physical and geometrical aspects of the models are also discussed.
Relations between task delegation and job satisfaction in general practice
DEFF Research Database (Denmark)
Riisgaard, Helle; Nexøe, Jørgen; Videbæk Le, Jette
2016-01-01
task delegation and general practitioners' and their staff's job satisfaction and, additionally, 2) to review the evidence of possible explanations for this relation. METHODS: A systematic literature review. We searched the four databases PubMed, Cinahl, Embase, and Scopus systematically. The immediate...
Related General-Vocabulary Knowledge Transfers to Learning Technical Terms
Balch, William R.
2015-01-01
In a classroom experiment during the first week of an introductory psychology course, randomly assigned students received a pretest and then a brief training on the definitions of general-vocabulary words either related (e.g., "facilitation") or unrelated (e.g., "rendition") to 16 technical terms (e.g., "social…
Galileons as the Scalar Analogue of General Relativity
Klein, Remko; Ozkan, Mehmet; Roest, Diederik
2016-01-01
We establish a correspondence between general relativity with diffeomorphism invariance and scalar field theories with Galilean invariance: notions such as the Levi-Civita connection and the Riemann tensor have a Galilean counterpart. This suggests Galilean theories as the unique nontrivial
Collineations of the curvature tensor in general relativity
Indian Academy of Sciences (India)
The general theory of relativity, which is a field theory of gravitation, is described by the Einstein field equations. These equations whose fundamental constituent is the space-time metric gij, are highly non-linear partial differential equations and, therefore it is very difficult to obtain exact solutions. They become still more diffi-.
Probing Students' Understanding of Some Conceptual Themes in General Relativity
Bandyopadhyay, Atanu; Kumar, Arvind
2010-01-01
This work is an attempt to see how physics undergraduates view the basic ideas of general relativity when they are exposed to the topic in a standard introductory course. Since the subject is conceptually and technically difficult, we adopted a "case studies" approach, focusing in depth on about six students who had just finished a one semester…
Anxiety and Test Anxiety: General and Test Anxiety among College Students with Learning Disabilities
Custodero, Jeri Lyn
2013-01-01
This study compares the state, trait, and test anxiety scores of 145 college students with and without learning disabilities against categories such as demographics, general anxiety, test anxiety, and disability experience. This study used a questionnaire and compared answers among groups. The analysis indicated that students with learning…
Gravitational redshift of galaxies in clusters as predicted by general relativity.
Wojtak, Radosław; Hansen, Steen H; Hjorth, Jens
2011-09-28
The theoretical framework of cosmology is mainly defined by gravity, of which general relativity is the current model. Recent tests of general relativity within the Lambda Cold Dark Matter (ΛCDM) model have found a concordance between predictions and the observations of the growth rate and clustering of the cosmic web. General relativity has not hitherto been tested on cosmological scales independently of the assumptions of the ΛCDM model. Here we report an observation of the gravitational redshift of light coming from galaxies in clusters at the 99 per cent confidence level, based on archival data. Our measurement agrees with the predictions of general relativity and its modification created to explain cosmic acceleration without the need for dark energy (the f(R) theory), but is inconsistent with alternative models designed to avoid the presence of dark matter. © 2011 Macmillan Publishers Limited. All rights reserved
A General Model for Testing Mediation and Moderation Effects
MacKinnon, David P.
2010-01-01
This paper describes methods for testing mediation and moderation effects in a dataset, both together and separately. Investigations of this kind are especially valuable in prevention research to obtain information on the process by which a program achieves its effects and whether the program is effective for subgroups of individuals. A general model that simultaneously estimates mediation and moderation effects is presented, and the utility of combining the effects into a single model is described. Possible effects of interest in the model are explained, as are statistical methods to assess these effects. The methods are further illustrated in a hypothetical prevention program example. PMID:19003535
Reformulation of the symmetries of first-order general relativity
Montesinos, Merced; González, Diego; Celada, Mariano; Díaz, Bogar
2017-10-01
We report a new internal gauge symmetry of the n-dimensional Palatini action with cosmological term (n>3 ) that is the generalization of three-dimensional local translations. This symmetry is obtained through the direct application of the converse of Noether’s second theorem on the theory under consideration. We show that diffeomorphisms can be expressed as linear combinations of it and local Lorentz transformations with field-dependent parameters up to terms involving the variational derivatives of the action. As a result, the new internal symmetry together with local Lorentz transformations can be adopted as the fundamental gauge symmetries of general relativity. Although their gauge algebra is open in general, it allows us to recover, without resorting to the equations of motion, the very well-known Lie algebra satisfied by translations and Lorentz transformations in three dimensions. We also report the analog of the new gauge symmetry for the Holst action with cosmological term, finding that it explicitly depends on the Immirzi parameter. The same result concerning its relation to diffeomorphisms and the open character of the gauge algebra also hold in this case. Finally, we consider the non-minimal coupling of a scalar field to gravity in n dimensions and establish that the new gauge symmetry is affected by this matter field. Our results indicate that general relativity in dimension greater than three can be thought of as a gauge theory.
Extent of the Immirzi ambiguity in quantum general relativity
Energy Technology Data Exchange (ETDEWEB)
Marugan, Guillermo A Mena [Centro de Fisica Miguel A Catalan, IMAFF, CSIC, Serrano 121, 28006 Madrid (Spain)
2002-04-21
The Ashtekar-Barbero formulation of general relativity admits a one-parameter family of canonical transformations that preserves the expressions of the Gauss and diffeomorphism constraints. The loop quantization of the connection formalism based on each of these canonical sets leads to different predictions. This phenomenon is called the Immirzi ambiguity. It has been recently argued that this ambiguity could be generalized to the extent of a spatially dependent function instead of a parameter. This would ruin the predictability of loop quantum gravity. We prove that such expectations are not realized, so that the Immirzi ambiguity introduces exclusively a freedom in the choice of a real number. (letter to the edit0008.
Experimental testing of constructivism and related theories.
Fidelman, U
1991-10-01
The purpose of this article is to show that experimental scientific methods can be applied to explain how the analytic mechanism of the left cerebral hemisphere and the synthetic mechanism of the right one create complex cognitive constructions like ontology and mathematics. Nominalism and ordinal mathematical concepts are related to the analytic left hemisphere while Platonism and cardinal mathematical concepts are related to the synthetic right one. Thus persons with a dominant left hemisphere tend to prefer nominalist ontology and have more aptitude for ordinal mathematics than for cardinal mathematics, while persons with a dominant right hemisphere tend to prefer platonist ontology and have more aptitude for cardinal mathematics than for ordinal mathematics. It is further explained how the Kantism temporal mode of perceiving experience can be related to the left hemisphere while the Kantian spatial mode of perceiving experience can be related to the right hemisphere. This relation can be tested experimentally, thus the Kantian source of constructivism, and through it constructivism itself, can be tested experimentally.
Testing the relation between percentage change and baseline value.
Tu, Yu-Kang
2016-03-16
Testing the relation between percentage change and baseline value has been controversial, but it is not clear why this practice may yield spurious results. In this paper, we first explained why the usual testing of the relation between percentage change and baseline value is inappropriate and then demonstrated how the appropriate null hypothesis could be formulated. We also proposed a simple procedure for testing the appropriate null hypothesis based on the assumption that when there is no relation between percentage change and baseline value, the coefficients of variation for repeated measurements of a random variable should remain unchanged. Two examples were used to demonstrate how the usual testing gave rise to misleading results, whilst results from our simple test were in general consistent with those from simulations. We also undertook simulations to investigate the impact of measurement errors on the performance of the proposed test. Results suggested the type-I error rates increased with the magnitude of measurement errors, whilst the statistical power to detect a genuine relation decreased. The usual approach to testing the relation between percentage change and baseline value tended to yield misleading results and should be avoided.
Visible Age-Related Signs and Risk of Ischemic Heart Disease in the General Population
DEFF Research Database (Denmark)
Christoffersen, Mette; Frikke-Schmidt, Ruth; Schnohr, Peter
2014-01-01
BACKGROUND: Cardiovascular disease is 1 of the most common age-related diseases, and also 1 of the most common causes of death in the general population. We tested the hypothesis that visible age-related signs associate with risk of ischemic heart disease (IHD), myocardial infarction (MI), and de...
Academic Training: Einstein and beyond: Introduction to General relativity
Françoise Benz
2005-01-01
2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 3, 4, 5, 6, 7 October from 11:00 to 12:00 - Main Auditorium, bldg. 500 Einstein and beyond: Introduction to General relativity by N. Straumann / Institut fur theoretische physics, Univ. Zürich We review the enduring achievements of Einstein's papers of 1905 and their impact on the further developments in physics. Program : Lectures I and II:Einstein's Contributions to Statistical Mechanics and Quantum Theory Lecture III:Einstein's Thesis at the University of Zürich Lecture IV: From Special to General Relativity Lecture V: The History and the Mystery of the Cosmological Constant ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch
A 4PN-exact approximation to General Relativity
Brizuela, David
2010-01-01
An approximation to General Relativity is presented which agrees with the Einstein field equations up to and including the fourth post-Newtonian (PN) order. This approximation is formulated in a fully constrained scheme: all involved equations are explicitly elliptic except the wave equation that describes the two independent degrees of freedom of the gravitational field. The formalism covers naturally the conformal-flat-condition (CFC) approach by Isenberg, Wilson, and Mathews and the improved second PN-order exact approach CFC+. For stationary configurations, like Kerr black holes, agreement with General Relativity is achieved even through 5PN order. In addition, we analyze in detail a particularly interesting 2PN-exact waveless approximation which results from imposing more restrictive conditions. The proposed scheme can be considered as a further development on the waveless approach suggested by Schaefer and Gopakumar [Phys. Rev. D {\\bf 69}, 021501 (2004)].
Prisacari, Anna Agripina
Research on the testing effect shows that practice tests are more effective than additional studying for enhancing learning. However, there has been little research directly addressing the role of additional testing when students take paper-based or computer-based tests in college courses. Accordingly, the purpose of this study was to investigate the role of the testing effect and test mode on student performance. The participants were 664 general chemistry students from two large universities in the Midwest and the Pacific Northwest. After covering the test material in their course, students completed two proctored practice tests that included 17 algorithmic question pairs, 5 conceptual pairs, and 2 definition pairs. Each practice test was delivered on computer or paper according to one of four conditions that were defined by the mode of the initial test and the mode of the final test. These conditions were: Computer-Computer, Computer-Paper, Paper-Computer, and Paper-Paper. After completing the initial practice test, students repeated half of the items. Feedback was provided after each test and performance was measured with normalized gains. After completing all of the tests, students were asked to indicate and explain their test mode preferences for general chemistry tests. Four major conclusions resulted from the study. First, the testing effect was found in all conditions, but varied in terms of the test mode. Paper-Computer showed the lowest gains and these gains were significantly lower than those for Paper-Paper. Gains from Computer-Paper and Paper-Paper were not significantly different from each other. Second, the test mode did not affect the students' performance on algorithmic questions, but affected their performance on conceptual and definition questions. Third, the gains from repeated items were significantly higher than the gains from non-repeated items. However, this testing effect was not consistent across all areas of chemistry content. Fourth, a
Classical and Quantum Two-Body Problem in General Relativity
Maheshwari, Amar; Todorov, Ivan
2016-01-01
The two-body problem in general relativity is reduced to the problem of an effective particle (with an energy-dependent relativistic reduced mass) in an external field. The effective potential is evaluated from the Born diagram of the linearized quantum theory of gravity. It reduces to a Schwarzschild-like potential with two different `Schwarzschild radii'. The results derived in a weak field approximation are expected to be relevant for relativistic velocities.
General relativity from three-forms in seven dimensions
Directory of Open Access Journals (Sweden)
Kirill Krasnov
2017-09-01
Full Text Available We consider a certain theory of 3-forms in 7 dimensions, and study its dimensional reduction to 4D, compactifying the 7-dimensional manifold on the 3-sphere of a fixed radius. We show that the resulting 4D theory is (Riemannian General Relativity (GR in Plebanski formulation, modulo corrections that are negligible for curvatures smaller than Planckian. Possibly the most interesting point of this construction is that the dimensionally reduced theory is GR with a non-zero cosmological constant, and the value of the cosmological constant is directly related to the size of S3. Realistic values of Λ correspond to S3 of Planck size.
Explanatory and illustrative visualization of special and general relativity.
Weiskopf, Daniel; Borchers, Marc; Ertl, Thomas; Falk, Martin; Fechtig, Oliver; Frank, Regine; Grave, Frank; King, Andreas; Kraus, Ute; Müller, Thomas; Nollert, Hans-Peter; Rica Mendez, Isabel; Ruder, Hanns; Schafhitzel, Tobias; Schär, Sonja; Zahn, Corvin; Zatloukal, Michael
2006-01-01
This paper describes methods for explanatory and illustrative visualizations used to communicate aspects of Einstein's theories of special and general relativity, their geometric structure, and of the related fields of cosmology and astrophysics. Our illustrations target a general audience of laypersons interested in relativity. We discuss visualization strategies, motivated by physics education and the didactics of mathematics, and describe what kind of visualization methods have proven to be useful for different types of media, such as still images in popular science magazines, film contributions to TV shows, oral presentations, or interactive museum installations. Our primary approach is to adopt an egocentric point of view: The recipients of a visualization participate in a visually enriched thought experiment that allows them to experience or explore a relativistic scenario. In addition, we often combine egocentric visualizations with more abstract illustrations based on an outside view in order to provide several presentations of the same phenomenon. Although our visualization tools often build upon existing methods and implementations, the underlying techniques have been improved by several novel technical contributions like image-based special relativistic rendering on GPUs, special relativistic 4D ray tracing for accelerating scene objects, an extension of general relativistic ray tracing to manifolds described by multiple charts, GPU-based interactive visualization of gravitational light deflection, as well as planetary terrain rendering. The usefulness and effectiveness of our visualizations are demonstrated by reporting on experiences with, and feedback from, recipients of visualizations and collaborators.
General pharmacology of pidotimod and testing for drug interactions.
Manzardo, S; Falcone, A; Pinzetta, A; Ieva, G; Coppi, G
1994-12-01
Pidotimod ((R)-3-[(S)-(5-oxo-2-pyrrolidinyl) carbonyl]-thiazolidine-4-carboxylic acid, PGT/1A, CAS 121808-62-6) is a new biological response modifier. General pharmacology and interactions with some drugs were tested. The drug, at doses of 200 mg/kg i.p. and 400 mg/kg p.o., did not affect the normal behaviour, did not modify the responses to stimulation of autonomic nervous system or central nervous system. Pidotimod did not display any cardiovascular or respiratory effect up to 125 mg/kg i.v. in 3 animal species. The drug did not show antimicrobial or antifungal activities nor interact with some of the most common therapeutics (antibiotics, tolbutamide, pentobarbital, antihypertensives, chlorothiazide, warfarin, non-steroidal antiinflammatory agents). On the basis of these results pidotimod shows a safe profile; moreover it does not interact with many therapeutic agents.
Testing Hardy-Weinberg disequilibrium using the generalized linear model.
Xu, Shizhong
2012-12-01
Current methods for detecting Hardy-Weinberg disequilibrium (HWD) only deal with one locus at a time. We developed a method that can jointly detect HWD for multiple loci. The method was developed under the generalized linear model (GLM) using the probit link function. When applied to a single locus, the new method is more powerful than the exact test. When applied to two or more loci, the method can reduce false positives caused by linkage disequilibrium (LD). We applied the method to 24 single nucleotide polymorphism (SNP) markers of a single human gene and eliminated several false positive HWDs due to LD. We developed an R package 'hwdglm' for joint HWD detection, which can be downloaded from our personal website (www.statgen.ucr.edu).
A New Generalization of von Neumann Relative Entropy
Li, Jing; Cao, Huaixin
2017-11-01
In quantum information, von Neumann relative entropy has a great applications and operational interpretations in diverse fields, and von Neumann entropy is an important tool for describing the uncertainty of a quantum state. In this paper, we generalize the classical von Neumann relative entropy S( ρ|| σ) and von Neumann entropy S( ρ) to f-von Neumann relative entropy \\widetilde {S}f(ρ ||σ ) and f-von Neumann entropy \\widetilde {S}f(ρ ) induced by a logarithm-like function f, respectively, and explore their properties. We prove that \\widetilde {S}f(ρ ||σ ) is nonnegative and then prove that \\widetilde {S}f(ρ ) has nonnegativity, boundedness, concavity, subadditivity and so on. Later, we show the stability and continuity of the \\widetilde {S}f(ρ ) with respect to the trace distance. In the case that f( x) = -log x, the resulted entropies reduce the classical von Neumann relative entropy and von Neumann entropy, respectively. This means that our results extend the usual results to a more general setting and then have some potential applications in quantum information.
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Dust, fume, and mist tests; respirators with filters; minimum requirements; general. 84.1158 Section 84.1158 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES...
Standard general relativity from Chern-Simons gravity
Energy Technology Data Exchange (ETDEWEB)
Izaurieta, F. [Departamento de Matematica y Fisica Aplicadas, Universidad, Catolica de la Santisima Concepcion, Alonso de Rivera 2850, Concepcion (Chile); Minning, P. [Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile); Perez, A. [Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile); Max Planck Institut fuer Gravitationsphysik, Albert Einstein, Institut. Am Muehlenberg1, D-14476 Golm bei Potsdam (Germany); Rodriguez, E. [Departamento de Matematica y Fisica Aplicadas, Universidad, Catolica de la Santisima Concepcion, Alonso de Rivera 2850, Concepcion (Chile); Salgado, P. [Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile)], E-mail: pasalgad@udec.cl
2009-07-13
Chern-Simons models for gravity are interesting because they provide a truly gauge-invariant action principle in the fiber-bundle sense. So far, their main drawback has largely been its perceived remoteness from standard General Relativity, based on the presence of higher powers of the curvature in the Lagrangian (except, remarkably, for three-dimensional spacetime). Here we report on a simple model that suggests a mechanism by which standard General Relativity in five-dimensional spacetime may indeed emerge at a special critical point in the space of couplings, where additional degrees of freedom and corresponding 'anomalous' Gauss-Bonnet constraints drop out from the Chern-Simons action. To achieve this goal, both the Lie algebra g and the symmetric g-invariant tensor that define the Chern-Simons Lagrangian are constructed by means of the Lie algebra S-expansion method with a suitable finite Abelian semigroup S. The results are generalized to arbitrary odd dimensions, and the possible extension to the case of eleven-dimensional supergravity is briefly discussed.
Generalized Symbolic Execution for Model Checking and Testing
Khurshid, Sarfraz; Pasareanu, Corina; Visser, Willem; Kofmeyer, David (Technical Monitor)
2003-01-01
Modern software systems, which often are concurrent and manipulate complex data structures must be extremely reliable. We present a novel framework based on symbolic execution, for automated checking of such systems. We provide a two-fold generalization of traditional symbolic execution based approaches: one, we define a program instrumentation, which enables standard model checkers to perform symbolic execution; two, we give a novel symbolic execution algorithm that handles dynamically allocated structures (e.g., lists and trees), method preconditions (e.g., acyclicity of lists), data (e.g., integers and strings) and concurrency. The program instrumentation enables a model checker to automatically explore program heap configurations (using a systematic treatment of aliasing) and manipulate logical formulae on program data values (using a decision procedure). We illustrate two applications of our framework: checking correctness of multi-threaded programs that take inputs from unbounded domains with complex structure and generation of non-isomorphic test inputs that satisfy a testing criterion. Our implementation for Java uses the Java PathFinder model checker.
Comment on "Construction of regular black holes in general relativity"
Bronnikov, Kirill A.
2017-12-01
We claim that the paper by Zhong-Ying Fan and Xiaobao Wang on nonlinear electrodynamics coupled to general relativity [Phys. Rev. D 94,124027 (2016)], although correct in general, in some respects repeats previously obtained results without giving proper references. There is also an important point missing in this paper, which is necessary for understanding the physics of the system: in solutions with an electric charge, a regular center requires a non-Maxwell behavior of Lagrangian function L (f ) , (f =Fμ νFμ ν) at small f . Therefore, in all electric regular black hole solutions with a Reissner-Nordström asymptotic, the Lagrangian L (f ) is different in different parts of space, and the electromagnetic field behaves in a singular way at surfaces where L (f ) suffers branching.
Boundary and Corner Terms in the Action for General Relativity
Jubb, Ian; Sorkin, Rafael; Surya, Sumati
2016-01-01
We revisit the action principle for general relativity motivated by the path integral approach to quantum gravity. We consider a spacetime region whose boundary has piecewise $C^2$ components, each of which can be spacelike, timelike or null and consider metric variations in which only the pullback of the metric to the boundary is held fixed. Allowing all such metric variations we present a unified treatment of the spacelike, timelike and null boundary components using Cartan's tetrad formalism. Apart from its computational simplicity, this formalism gives us a simple way of identifying corner terms. We also discuss "creases" which occur when the boundary is the event horizon of a black hole. Our treatment is geometric and intrinsic and we present our results both in the computationally simpler tetrad formalism as well as the more familiar metric formalism. We recover known results from a simpler and more general point of view and find some new ones.
AB INITIO PULSAR MAGNETOSPHERE: THE ROLE OF GENERAL RELATIVITY
Energy Technology Data Exchange (ETDEWEB)
Philippov, Alexander A.; Cerutti, Benoit; Spitkovsky, Anatoly [Department of Astrophysical Sciences, Princeton University, Ivy Lane, Princeton, NJ 08544 (United States); Tchekhovskoy, Alexander, E-mail: sashaph@princeton.edu [Departments of Physics and Astronomy, University of California, Berkeley, CA 94720 (United States)
2015-12-20
It has recently been demonstrated that self-consistent particle-in-cell simulations of low-obliquity pulsar magnetospheres in flat spacetime show weak particle acceleration and no pair production near the poles. We investigate the validity of this conclusion in a more realistic spacetime geometry via general-relativistic particle-in-cell simulations of the aligned pulsar magnetosphere with pair formation. We find that the addition of the frame-dragging effect makes the local current density along the magnetic field larger than the Goldreich–Julian value, which leads to unscreened parallel electric fields and the ignition of a pair cascade. When pair production is active, we observe field oscillations in the open field bundle, which could be related to pulsar radio emission. We conclude that general-relativistic effects are essential for the existence of the pulsar mechanism in low-obliquity rotators.
General Mission Analysis Tool (GMAT) Acceptance Test Plan [Draft
Dove, Edwin; Hughes, Steve
2007-01-01
The information presented in this Acceptance Test Plan document shows the current status of the General Mission Analysis Tool (GMAT). GMAT is a software system developed by NASA Goddard Space Flight Center (GSFC) in collaboration with the private sector. The GMAT development team continuously performs acceptance tests in order to verify that the software continues to operate properly after updates are made. The GMAT Development team consists of NASA/GSFC Code 583 software developers, NASA/GSFC Code 595 analysts, and contractors of varying professions. GMAT was developed to provide a development approach that maintains involvement from the private sector and academia, encourages collaborative funding from multiple government agencies and the private sector, and promotes the transfer of technology from government funded research to the private sector. GMAT contains many capabilities, such as integrated formation flying modeling and MATLAB compatibility. The propagation capabilities in GMAT allow for fully coupled dynamics modeling of multiple spacecraft, in any flight regime. Other capabilities in GMAT inclucle: user definable coordinate systems, 3-D graphics in any coordinate system GMAT can calculate, 2-D plots, branch commands, solvers, optimizers, GMAT functions, planetary ephemeris sources including DE405, DE200, SLP and analytic models, script events, impulsive and finite maneuver models, and many more. GMAT runs on Windows, Mac, and Linux platforms. Both the Graphical User Interface (GUI) and the GMAT engine were built and tested on all of the mentioned platforms. GMAT was designed for intuitive use from both the GUI and with an importable script language similar to that of MATLAB.
Further summation formulae related to generalized harmonic numbers
Zheng, De-Yin
2007-11-01
By employing the univariate series expansion of classical hypergeometric series formulae, Shen [L.-C. Shen, Remarks on some integrals and series involving the Stirling numbers and [zeta](n), Trans. Amer. Math. Soc. 347 (1995) 1391-1399] and Choi and Srivastava [J. Choi, H.M. Srivastava, Certain classes of infinite series, Monatsh. Math. 127 (1999) 15-25; J. Choi, H.M. Srivastava, Explicit evaluation of Euler and related sums, Ramanujan J. 10 (2005) 51-70] investigated the evaluation of infinite series related to generalized harmonic numbers. More summation formulae have systematically been derived by Chu [W. Chu, Hypergeometric series and the Riemann Zeta function, Acta Arith. 82 (1997) 103-118], who developed fully this approach to the multivariate case. The present paper will explore the hypergeometric series method further and establish numerous summation formulae expressing infinite series related to generalized harmonic numbers in terms of the Riemann Zeta function [zeta](m) with m=5,6,7, including several known ones as examples.
The revival of General Relativity at Princeton: Daring Conservatism
Brill, Dieter; Blum, Alexander
2018-01-01
After General Relativity was established in essentially its present form in 1915 it was celebrated as a great success of mathematical physics. But the initial hopes for this theory as a basis for all of physics began to fade in the next several decades, as General Relativity was relegated to the margins of theoretical physics. Its fate began to rise in the 1950's in a revival of interest and research that over time made gravitational physics one of the hottest research topics it is today. One center of this renaissance was Princeton, where two relative newcomers explored new and different approaches to gravitational physics. Robert Dicke showed that gravity is not as inaccessible to experiment as was thought, and John Wheeler propelled it into the mainstream by proposing highly original and imaginative consequences of Einstein's theory. We will concentrate on these ideas that, in his characteristically intriguing style, Wheeler called "Daring Conservatism" - a term well known to his associates, but one he never mentioned in print. With the aid of unpublished manuscripts and notes we will explore Daring Conservatism's origin and motivation, its successes and failures, and the legacy it left behind.
Probing Strong-field General Relativity with Gravitational Waves
Pretorius, Frans
We are on the verge of a new era in astrophysics as a world-wide effort to observe the universe with gravitational waves takes hold---ground based laser interferometers (Hz to kHz), pulsar timing (micro to nano Hz), measurements of polarization of the cosmic microwave background (sub-nano Hz), and the planned NASA/ESA mission LISA (.1 mHz to .1 Hz). This project will study the theoretical nature of gravitational waves (GWs) emitted by two sources in the LISA band, namely supermassive-black-hole (SMBH) binary mergers, and extreme-mass-ratio-inspirals (EMRI's)---the merger of a stellar mass black hole, neutron star, or white dwarf with a SMBH. The primary goal will be to ascertain how well LISA, by observing these sources, could answer the following related questions about the fundamental nature of strong-field gravity: Does Einstein's theory of general relativity (GR) describe the geometry of black holes in the universe? What constraints can GW observations of SMBH mergers and EMRIs place on alternative theories of gravity? If there are deviations from GR, are there statistics that could give indications of a deviation if sources are detected using a search strategy based solely on GR waveforms? The primary reasons for focusing on LISA sources to answer these questions are (a) binary SMBH mergers could be detected by LISA with exquisitely high signal-to- noise, allowing enough parameters of the system to be accurately extracted to perform consistency checks of the underlying theory, (b) EMRIs will spend numerous orbits close to the central black hole, and thus will be quite sensitive to even small near-horizon deviations from GR. One approach to develop the requisite knowledge and tools to answer these questions is to study a concrete, theoretically viable alternative to GR. We will focus on the dynamical variant of Chern-Simons modified gravity (CSMG), which is interesting for several reasons, chief among which are (1) that CSMG generically arises in both string
Bitopological spaces theory, relations with generalized algebraic structures and applications
Dvalishvili, Badri
2005-01-01
This monograph is the first and an initial introduction to the theory of bitopological spaces and its applications. In particular, different families of subsets of bitopological spaces are introduced and various relations between two topologies are analyzed on one and the same set; the theory of dimension of bitopological spaces and the theory of Baire bitopological spaces are constructed, and various classes of mappings of bitopological spaces are studied. The previously known results as well the results obtained in this monograph are applied in analysis, potential theory, general topology, a
General Video Game Evaluation Using Relative Algorithm Performance Profiles
DEFF Research Database (Denmark)
Nielsen, Thorbjørn; Barros, Gabriella; Togelius, Julian
2015-01-01
In order to generate complete games through evolution we need generic and reliably evaluation functions for games. It has been suggested that game quality could be characterised through playing a game with different controllers and comparing their performance. This paper explores that idea through...... investigating the relative performance of different general game-playing algorithms. Seven game-playing algorithms was used to play several hand-designed, mutated and randomly generated VGDL game descriptions. Results discussed appear to support the conjecture that well-designed games have, in average, a higher...... performance difference between better and worse game-playing algorithms....
Evolving black hole horizons in General Relativity and alternative gravity
Faraoni, Valerio
2013-01-01
From the microscopic point of view, realistic black holes are time-dependent and the teleological concept of event horizon fails. At present, the apparent or the trapping horizon seem its best replacements in various areas of black hole physics. We discuss the known phenomenology of apparent and trapping horizons for analytical solutions of General Relativity and alternative theories of gravity. These specific examples (we focus on spherically symmetric inhomogeneities in a background cosmological spacetime) may be useful as toy models for research on various aspects of black hole physics.
Evolving Black Hole Horizons in General Relativity and Alternative Gravity
Directory of Open Access Journals (Sweden)
Valerio Faraoni
2013-09-01
Full Text Available From the microscopic point of view, realistic black holes are time-dependent and the teleological concept of the event horizon fails. At present, the apparent or trapping horizon seem to be its best replacements in various areas of black hole physics. We discuss the known phenomenology of apparent and trapping horizons for analytical solutions of General Relativity and alternative theories of gravity. These specific examples (we focus on spherically symmetric inhomogeneities in a background cosmological spacetime are useful as toy models for research on various aspects of black hole physics.
Kerr-Taub-NUT General Frame, Energy, and Momentum in Teleparallel Equivalent of General Relativity
Directory of Open Access Journals (Sweden)
Gamal G. L. Nashed
2012-01-01
Full Text Available A new exact solution describing a general stationary and axisymmetric object of the gravitational field in the framework of teleparallel equivalent of general relativity (TEGR is derived. The solution is characterized by three parameters “the gravitational mass M, the rotation a, and the NUT L.” The vierbein field is axially symmetric, and the associated metric gives the Kerr-Taub-NUT spacetime. Calculation of the total energy using two different methods, the gravitational energy momentum and the Riemannian connection 1-form Γα̃β, is carried out. It is shown that the two methods give the same results of energy and momentum. The value of energy is shown to depend on the mass M and the NUT parameter L. If L is vanishing, then the total energy reduced to the energy of Kerr black hole.
Gyroscope precession in special and general relativity from basic principles
Jonsson, Rickard M.
2007-05-01
In special relativity a gyroscope that is suspended in a torque-free manner will precess as it is moved along a curved path relative to an inertial frame S. We explain this effect, which is known as Thomas precession, by considering a real grid that moves along with the gyroscope, and that by definition is not rotating as observed from its own momentary inertial rest frame. From the basic properties of the Lorentz transformation we deduce how the form and rotation of the grid (and hence the gyroscope) will evolve relative to S. As an intermediate step we consider how the grid would appear if it were not length contracted along the direction of motion. We show that the uncontracted grid obeys a simple law of rotation. This law simplifies the analysis of spin precession compared to more traditional approaches based on Fermi transport. We also consider gyroscope precession relative to an accelerated reference frame and show that there are extra precession effects that can be explained in a way analogous to the Thomas precession. Although fully relativistically correct, the entire analysis is carried out using three-vectors. By using the equivalence principle the formalism can also be applied to static spacetimes in general relativity. As an example, we calculate the precession of a gyroscope orbiting a static black hole.
Victorson, David; Beaumont, Jennifer L; Mahadevan, Rupa; Grimone, Ania; Burns, Virginia; Murry, Wendy; Gutierrez, Sandra; Schuette, Stephanie; Brady, Caitlin; Ring, Melinda
2016-10-01
Acupuncture has been shown to alleviate symptoms and increase general well-being in different medical patient samples. A major challenge in acupuncture clinical research is the availability of comparable and standardized patient-reported outcome measurement (PRO) tools. This study used a pragmatic design to examine longitudinal changes in quality of life (QOL) in a medical patient sample following acupuncture using PROs from the National Institutes of Health's Patient Reported Outcomes Measurement Information System (PROMIS) initiative. It also examined the role of acupuncture expectancies, as well as patient and provider perceptions of acupuncture benefit. Following informed consent, patients completed baseline QOL measures (T1) prior to their first acupuncture session. Subsequent assessments (up to 20) were completed immediately following ensuing acupuncture sessions. Patients completed assessments either on a touch-screen computer at the clinic or from their home computer. Compared with acupuncture-naïve participants, those who received prior acupuncture treatment reported significantly higher anxiety, fatigue, sleep disturbance, and lower positive affect at baseline. By the second assessment, however, these differences became nonexistent. Participants who held greater baseline acupuncture expectations (e.g., their situation would improve a lot, they would have improved coping skills, their symptoms would disappear, their energy would increase) reported significantly higher fatigue, pain interference, and problems with physical functioning. Between T1 and T2, all participants reported significant improvements in anxiety, depression, and fatigue. Exploratory longitudinal models demonstrated significant linear improvements over time in anxiety (p = 0.006), depression (p = 0.007), pain interference (p acupuncture expectations highlighted subgroup differences in outcomes at baseline, linear-growth models demonstrated the positive effects of acupuncture
Theory of Nonlocal Point Transformations in General Relativity
Directory of Open Access Journals (Sweden)
Massimo Tessarotto
2016-01-01
Full Text Available A discussion of the functional setting customarily adopted in General Relativity (GR is proposed. This is based on the introduction of the notion of nonlocal point transformations (NLPTs. While allowing the extension of the traditional concept of GR-reference frame, NLPTs are important because they permit the explicit determination of the map between intrinsically different and generally curved space-times expressed in arbitrary coordinate systems. For this purpose in the paper the mathematical foundations of NLPT-theory are laid down and basic physical implications are considered. In particular, explicit applications of the theory are proposed, which concern (1 a solution to the so-called Einstein teleparallel problem in the framework of NLPT-theory; (2 the determination of the tensor transformation laws holding for the acceleration 4-tensor with respect to the group of NLPTs and the identification of NLPT-acceleration effects, namely, the relationship established via general NLPT between particle 4-acceleration tensors existing in different curved space-times; (3 the construction of the nonlocal transformation law connecting different diagonal metric tensors solution to the Einstein field equations; and (4 the diagonalization of nondiagonal metric tensors.
Einstein and Beyond: A Critical Perspective on General Relativity
Directory of Open Access Journals (Sweden)
Ram Gopal Vishwakarma
2016-05-01
Full Text Available An alternative approach to Einstein’s theory of General Relativity (GR is reviewed, which is motivated by a range of serious theoretical issues inflicting the theory, such as the cosmological constant problem, presence of non-Machian solutions, problems related with the energy-stress tensor T i k and unphysical solutions. The new approach emanates from a critical analysis of these problems, providing a novel insight that the matter fields, together with the ensuing gravitational field, are already present inherently in the spacetime without taking recourse to T i k . Supported by lots of evidence, the new insight revolutionizes our views on the representation of the source of gravitation and establishes the spacetime itself as the source, which becomes crucial for understanding the unresolved issues in a unified manner. This leads to a new paradigm in GR by establishing equation R i k = 0 as the field equation of gravitation plus inertia in the very presence of matter.
The problem of time quantum mechanics versus general relativity
Anderson, Edward
2017-01-01
This book is a treatise on time and on background independence in physics. It first considers how time is conceived of in each accepted paradigm of physics: Newtonian, special relativity, quantum mechanics (QM) and general relativity (GR). Substantial differences are moreover uncovered between what is meant by time in QM and in GR. These differences jointly source the Problem of Time: Nine interlinked facets which arise upon attempting concurrent treatment of the QM and GR paradigms, as is required in particular for a background independent theory of quantum gravity. A sizeable proportion of current quantum gravity programs - e.g. geometrodynamical and loop quantum gravity approaches to quantum GR, quantum cosmology, supergravity and M-theory - are background independent in this sense. This book's foundational topic is thus furthermore of practical relevance in the ongoing development of quantum gravity programs. This book shows moreover that eight of the nine facets of the Problem of Time already occur upon ...
The general public's understanding and perception of direct-to-consumer genetic test results.
Leighton, J W; Valverde, K; Bernhardt, B A
2012-01-01
Direct-to-consumer (DTC) genetic testing allows consumers to discover their risk for common complex disorders. The extent to which consumers understand typical results provided by DTC genetic testing is currently unknown. Misunderstanding of the results could lead to negative consequences including unnecessary concern, false reassurance or unwarranted changes in screening behaviors. We conducted a study to investigate consumers' perceptions and understanding of DTC test results. An online survey was posted on Facebook that included questions relating to 4 sample test results for risk of developing colorectal cancer, heart disease and skin cancer. Genetic counselors were used as a comparison group. 145 individuals from the general public and 171 genetic counselors completed the survey. A significant difference was found between the way the general public and genetic counselors interpreted the meaning of the DTC results. The general public respondents also believed that results in all 4 scenarios would be significantly more helpful than the genetic counselors did. Although the majority of general public respondents rated the results as easy to understand, they often misinterpreted them. These findings imply that the general public has the potential to misinterpret DTC results without appropriate assistance. Further research is needed to explore optimal methods of providing DTC test results and ways to minimize the risk of negative consequences for consumers. Copyright © 2011 S. Karger AG, Basel.
General Framework for Meta-Analysis of Haplotype Association Tests.
Wang, Shuai; Zhao, Jing Hua; An, Ping; Guo, Xiuqing; Jensen, Richard A; Marten, Jonathan; Huffman, Jennifer E; Meidtner, Karina; Boeing, Heiner; Campbell, Archie; Rice, Kenneth M; Scott, Robert A; Yao, Jie; Schulze, Matthias B; Wareham, Nicholas J; Borecki, Ingrid B; Province, Michael A; Rotter, Jerome I; Hayward, Caroline; Goodarzi, Mark O; Meigs, James B; Dupuis, Josée
2016-04-01
For complex traits, most associated single nucleotide variants (SNV) discovered to date have a small effect, and detection of association is only possible with large sample sizes. Because of patient confidentiality concerns, it is often not possible to pool genetic data from multiple cohorts, and meta-analysis has emerged as the method of choice to combine results from multiple studies. Many meta-analysis methods are available for single SNV analyses. As new approaches allow the capture of low frequency and rare genetic variation, it is of interest to jointly consider multiple variants to improve power. However, for the analysis of haplotypes formed by multiple SNVs, meta-analysis remains a challenge, because different haplotypes may be observed across studies. We propose a two-stage meta-analysis approach to combine haplotype analysis results. In the first stage, each cohort estimate haplotype effect sizes in a regression framework, accounting for relatedness among observations if appropriate. For the second stage, we use a multivariate generalized least square meta-analysis approach to combine haplotype effect estimates from multiple cohorts. Haplotype-specific association tests and a global test of independence between haplotypes and traits are obtained within our framework. We demonstrate through simulation studies that we control the type-I error rate, and our approach is more powerful than inverse variance weighted meta-analysis of single SNV analysis when haplotype effects are present. We replicate a published haplotype association between fasting glucose-associated locus (G6PC2) and fasting glucose in seven studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium and we provide more precise haplotype effect estimates. © 2016 WILEY PERIODICALS, INC.
Bindels, Patrick; Dinant, Geert-Jan; Grol, Richard; Koch, Helen; Bokhoven, van Marloes; Weijden, van der Trudy
2006-01-01
BACKGROUND:General practitioners (GPs) frequently order blood tests when they see patients presenting with unexplained complaints. Due to the low prevalence of serious pathology in general practice, the risk of false-positive test results is relatively high. This may result in unnecessary further
van Bokhoven, Marloes A.; Koch, Hèlen; van der Weijden, Trudy; Grol, Richard P. T. M.; Bindels, Patrick J. E.; Dinant, Geert-Jan
2006-01-01
BACKGROUND: General practitioners (GPs) frequently order blood tests when they see patients presenting with unexplained complaints. Due to the low prevalence of serious pathology in general practice, the risk of false-positive test results is relatively high. This may result in unnecessary further
49 CFR 219.11 - General conditions for chemical tests.
2010-10-01
... construed to authorize the use of physical coercion or any other deprivation of liberty in order to compel... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CONTROL OF ALCOHOL AND DRUG USE General § 219.11 General conditions...
New Probe of Departures from General Relativity Using Minkowski Functionals.
Fang, Wenjuan; Li, Baojiu; Zhao, Gong-Bo
2017-05-05
The morphological properties of the large scale structure of the Universe can be fully described by four Minkowski functionals (MFs), which provide important complementary information to other statistical observables such as the widely used 2-point statistics in configuration and Fourier spaces. In this work, for the first time, we present the differences in the morphology of the large scale structure caused by modifications to general relativity (to address the cosmic acceleration problem), by measuring the MFs from N-body simulations of modified gravity and general relativity. We find strong statistical power when using the MFs to constrain modified theories of gravity: with a galaxy survey that has survey volume ∼0.125(h^{-1} Gpc)^{3} and galaxy number density ∼1/(h^{-1} Mpc)^{3}, the two normal-branch Dvali-Gabadadze-Porrati models and the F5 f(R) model that we simulated can be discriminated from the ΛCDM model at a significance level ≳5σ with an individual MF measurement. Therefore, the MF of the large scale structure is potentially a powerful probe of gravity, and its application to real data deserves active exploration.
Vocabulary test format and differential relations to age.
Bowles, Ryan P; Salthouse, Timothy A
2008-06-01
Although vocabulary tests are generally considered interchangeable, regardless of format, different tests can have different relations to age and to other cognitive abilities. In this study, 4 vocabulary test formats were examined: multiple-choice synonyms, multiple-choice antonyms, produce the definition, and picture identification. Results indicated that, although they form a single coherent vocabulary knowledge factor, the formats have different relations to age. In earlier adulthood, picture identification had the strongest growth, and produce the definition had the weakest. In later adulthood, picture identification had the strongest decline, and multiple-choice synonyms had the least. The formats differed in their relation to other cognitive variables, including reasoning, spatial visualization, memory, and speed. After accounting for the differential relations to other cognitive variables, differences in relation to age were eliminated with the exception of differences for the picture identification test. No theory of the aging of vocabulary knowledge fully explains these findings. These results suggest that using a single indicator of vocabulary may yield incomplete and somewhat misleading results about the aging of vocabulary knowledge.
Solar energy utilization by a greenhouse: General relations
Energy Technology Data Exchange (ETDEWEB)
Abdel-Ghany, A.M.; Al-Helal, I.M. [Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, PO box 2460, Riyadh 11451 (Saudi Arabia)
2011-01-15
Most of solar radiation incident on a greenhouse is absorbed by greenhouse components (i.e., the cover, humid air, plants and soil) and the remaining portion is lost to outside the greenhouse. It is essential to know the absorbed and lost energy terms for any thermal analysis of greenhouses. Existing greenhouse thermal models use the radiative properties of the greenhouse components to directly determine the absorbed energy terms. However, these models neglect the lost energy term and neglect the effects of the multiple reflections of solar radiation between the greenhouse components. The present study describes the general relations for estimating the amounts of solar energy absorbed by the greenhouse components and lost to outside the greenhouse. The relations take into consideration the interrelations as well as the multiple reflections of solar radiation between these components. Thus, the greenhouse system was treated as a solar collector having an absorber plate (i.e., the greenhouse soil) and a cover system consisting of three semi-transparent parallel layers (i.e., the greenhouse cover, the humid air, and the plants). Superposition theory and ray tracing technique were used for the analysis. The presented relations were applied to an experimental plastic-covered greenhouse with a floor area of 34 m{sup 2}. The greenhouse, located in Riyadh, Saudi Arabia, was planted with tomatoes with a leaf area index (LAI) of 3.0 and was cooled by a wet pad and fan system. Results of the presented relations were accurate and more realistic comparing to results of other relations reported in the literatures. Absorption of solar radiation by water vapor in the greenhouse was negligible. The presented relations can estimate the absorbed and lost energy terms for a greenhouse precisely with a max possible error of +1.8% on each term if the LAI was less than 1.5. The error is significantly decreased to less than +0.7% if the LAI in the greenhouse is increased to 5. (author)
Generalized Chaplygin Gas Models Tested with Type Ia Supernovae
Biesiada, Marek; Godłowski, Włodzimierz; Szydłowski, Marek
2005-03-01
The generalized Chaplygin gas (GCG), with the equation of state p=-A/ρα, was recently proposed as a candidate for dark energy in the universe. In this paper we confront the GCG with Type Ia supernova (SN Ia) data using available samples. Specifically, we have tested the GCG cosmology in three different classes of models with (1) Ωm=0.3 and ΩCh=0.7, (2) Ωm=0.05 and ΩCh=0.95, and (3) Ωm=0 and ΩCh=1, as well as a model without prior assumptions on Ωm. The best-fit models are obtained by minimizing the χ2 function. We supplement our analysis with confidence intervals in the (A0, α)-plane by marginalizing the probability density functions (pdf's) over the remaining parameters assuming uniform priors. We have also derived one-dimensional pdf's for ΩCh obtained from joint marginalization over α and A0. The maximum value of such a pdf provides the most probable value of ΩCh within the full class of GCG models. The general conclusion is that SN Ia data give support to the Chaplygin gas (with α=1). However, a noticeable preference for A0-values close to 1 means that the α dependence becomes insignificant. This is reflected in one-dimensional pdf's for α that turned out to be flat, meaning that the power of the present supernova data to discriminate between various GCG models (differing by α) is weak. Extending our analysis by relaxing the prior assumption of the flatness of the universe leads to the result that even though the best-fit values of Ωk are formally nonzero, they are still close to the flat case. Our results show clearly that in GCG cosmology, distant (i.e., z>1) supernovae should be brighter than in the ΛCDM model. Therefore, one can expect that future supernova experiments (e.g., SNAP) having access to higher redshifts will eventually resolve the issue of whether the dark energy content of the universe could be described as a Chaplygin gas. Moreover, it would be possible to differentiate between models with various values of the
DEFF Research Database (Denmark)
Thompson, Mary Kathryn; Clemmensen, Line Katrine Harder
2015-01-01
The design of experimental test parts to characterize micro additive manufacturing (AM) processes is challenging due to the influence of the manufacturing and metrology processes. This work builds on the lessons learned from a case study in the literature to derive generalized requirements and high...... level decompositions for the design of test parts and the design of experiments to characterize micro additive manufacturing processes. While the test parts and the experiments described are still work in progress, the generic requirements derived from them can serve as a starting point for the design...... of other micro additive manufacturing related studies and their decompositions can help structure future work....
On the relation between barycentric and "good" geocentric coordinates in general relativity.
Soffel, M.; Xu, Chongming
The problem of "good" geocentric coordinates in the framework of general relativity is discussed. The recent work by Brumberg and Kopejkin suggests that the use of harmonic, non-rotating and comoving coordinates has several advantages over the use of generalized Fermi normal coordinates. The technique of matching the global (barycentric) with the local (geocentric) metric then not only determines the geocentric metric and the coordinate transformation between global and local coordinates but also the equations of motion.
Outer boundary as arrested history in general relativity
Lau, S
2002-01-01
We present explicit outer boundary conditions for the canonical variables of general relativity. The conditions are associated with the causal evolution of a finite Cauchy domain, a so-called quasilocal boost, and they suggest a consistent scheme for modelling such an evolution numerically. The scheme involves a continuous boost in the spacetime orthogonal complement 'orthogonal' T sub p (B) of the tangent space T sub p (B) belonging to each point p on the system boundary B. We show how the boost rate may be computed numerically via equations similar to those appearing in canonical investigations of black-hole thermodynamics (although here holding at an outer two-surface rather than the bifurcate two-surface of a Killing horizon). We demonstrate the numerical scheme on a model example, the quasilocal boost of a spherical three-ball in Minkowski spacetime. Developing our general formalism with recent hyperbolic formulations of the Einstein equations in mind, we use Anderson and York's 'Einstein-Christoffel' hy...
Collapse of magnetized hypermassive neutron stars in general relativity.
Duez, Matthew D; Liu, Yuk Tung; Shapiro, Stuart L; Shibata, Masaru; Stephens, Branson C
2006-01-27
Hypermassive neutron stars (HMNSs)--equilibrium configurations supported against collapse by rapid differential rotation--are possible transient remnants of binary neutron-star mergers. Using newly developed codes for magnetohydrodynamic simulations in dynamical spacetimes, we are able to track the evolution of a magnetized HMNS in full general relativity for the first time. We find that secular angular momentum transport due to magnetic braking and the magnetorotational instability results in the collapse of an HMNS to a rotating black hole, accompanied by a gravitational wave burst. The nascent black hole is surrounded by a hot, massive torus undergoing quasistationary accretion and a collimated magnetic field. This scenario suggests that HMNS collapse is a possible candidate for the central engine of short gamma-ray bursts.
Commutative deformations of general relativity: nonlocality, causality, and dark matter
Energy Technology Data Exchange (ETDEWEB)
De Vegvar, P.G.N. [SWK Research, Bellingham, WA (United States)
2017-01-15
Hopf algebra methods are applied to study Drinfeld twists of (3+1)-diffeomorphisms and deformed general relativity on commutative manifolds. A classical nonlocality length scale is produced above which microcausality emerges. Matter fields are utilized to generate self-consistent Abelian Drinfeld twists in a background independent manner and their continuous and discrete symmetries are examined. There is negligible experimental effect on the standard model of particles. While baryonic twist producing matter would begin to behave acausally for rest masses above ∝1-10 TeV, other possibilities are viable dark matter candidates or a right-handed neutrino. First order deformed Maxwell equations are derived and yield immeasurably small cosmological dispersion and produce a propagation horizon only for photons at or above Planck energies. This model incorporates dark matter without any appeal to extra dimensions, supersymmetry, strings, grand unified theories, mirror worlds, or modifications of Newtonian dynamics. (orig.)
Cosmology in time asymmetric extensions of general relativity
Leon, Genly
2015-01-01
We investigate the cosmological behavior in a universe governed by time asymmetric extensions of general relativity, which is a novel modified gravity based on the addition of new, time-asymmetric, terms on the Hamiltonian framework, in a way that the algebra of constraints and local physics remain unchanged. Nevertheless, at cosmological scales these new terms can have significant effects that can alter the universe evolution, both at early and late times, and the freedom in the choice of the involved modification function makes the scenario able to produce a huge class of cosmological behaviors. For basic ansatzes of modification, we perform a detailed dynamical analysis, extracting the stable late time solutions. Amongst others, we find that the universe can result in dark-energy dominated, accelerating solutions, even in the absence of an explicit cosmological constant, in which the dark energy can be quintessence-like, phantom-like, or behave as an effective cosmological constant. Moreover, it can result...
CPT symmetry and antimatter gravity in general relativity
Villata, M
2011-01-01
The gravitational behavior of antimatter is still unknown. While we may be confident that antimatter is self-attractive, the interaction between matter and antimatter might be either attractive or repulsive. We investigate this issue on theoretical grounds. Starting from the CPT invariance of physical laws, we transform matter into antimatter in the equations of both electrodynamics and gravitation. In the former case, the result is the well-known change of sign of the electric charge. In the latter, we find that the gravitational interaction between matter and antimatter is a mutual repulsion, i.e. antigravity appears as a prediction of general relativity when CPT is applied. This result supports cosmological models attempting to explain the Universe accelerated expansion in terms of a matter-antimatter repulsive interaction.
CPT symmetry and antimatter gravity in general relativity
Villata, M.
2011-04-01
The gravitational behavior of antimatter is still unknown. While we may be confident that antimatter is self-attractive, the interaction between matter and antimatter might be either attractive or repulsive. We investigate this issue on theoretical grounds. Starting from the CPT invariance of physical laws, we transform matter into antimatter in the equations of both electrodynamics and gravitation. In the former case, the result is the well-known change of sign of the electric charge. In the latter, we find that the gravitational interaction between matter and antimatter is a mutual repulsion, i.e. antigravity appears as a prediction of general relativity when CPT is applied. This result supports cosmological models attempting to explain the Universe accelerated expansion in terms of a matter-antimatter repulsive interaction.
Gravitating vortons as ring solitons in general relativity
Kunz, Jutta; Subagyo, Bintoro
2013-01-01
Vortons can be viewed as (flat space-) field theory analogs of black rings in general relativity. They are made from loops of vortices, being sustained against collapse by the centrifugal force. In this work we discuss such configurations in the global version of Witten's U(1)xU(1) theory. We first consider solutions in a flat spacetime background and show their non-uniqueness. The inclusion of gravity leads to new features. In particular, an ergoregion can occur. Also, similar to boson stars, we show that the vortons exist only in a limited frequency range. The coupling to gravity gives rise to a spiral-like frequency dependence of the mass and charge. New solutions of the model describing 'semitopological vortons' and 'di-vortons' are also discussed.
General Relativity and Cosmology: Unsolved Questions and Future Directions
Directory of Open Access Journals (Sweden)
Ivan Debono
2016-09-01
Full Text Available For the last 100 years, General Relativity (GR has taken over the gravitational theory mantle held by Newtonian Gravity for the previous 200 years. This article reviews the status of GR in terms of its self-consistency, completeness, and the evidence provided by observations, which have allowed GR to remain the champion of gravitational theories against several other classes of competing theories. We pay particular attention to the role of GR and gravity in cosmology, one of the areas in which one gravity dominates and new phenomena and effects challenge the orthodoxy. We also review other areas where there are likely conflicts pointing to the need to replace or revise GR to represent correctly observations and consistent theoretical framework. Observations have long been key both to the theoretical liveliness and viability of GR. We conclude with a discussion of the likely developments over the next 100 years.
Hydrodynamics in full general relativity with conservative AMR
East, William E; Stephens, Branson C
2011-01-01
There is great interest in numerical relativity simulations involving matter due to the likelihood that binary compact objects (BCOs) involving neutron stars will be detected by gravitational wave observatories in the coming years, as well as to the possibility that BCO mergers could explain short-duration gamma-ray bursts. We present a code designed for simulations of hydrodynamics coupled to the Einstein field equations targeted toward such applications. This code has recently been used to study eccentric mergers of black hole-neutron star binaries. We evolve the fluid conservatively using high-resolution shock capturing methods, while the field equations are solved in the generalized harmonic formulation with finite differences. In order to resolve the various scales that may arise, we use adaptive mesh refinement (AMR) with grid hierarchies based on truncation error estimates. A noteworthy feature of this code is the implementation of the flux correction algorithm of Berger and Colella to ensure that cons...
Generalized Convex Functions on Fractal Sets and Two Related Inequalities
Directory of Open Access Journals (Sweden)
Huixia Mo
2014-01-01
Full Text Available We introduce the generalized convex function on fractal sets Rα (0<α≤1 of real line numbers and study the properties of the generalized convex function. Based on these properties, we establish the generalized Jensen’s inequality and generalized Hermite-Hadamard's inequality. Furthermore, some applications are given.
Generality of leaf trait relationships: A test across six biomes
Energy Technology Data Exchange (ETDEWEB)
Reich, P.B. [Univ. of Minnesota, Saint Paul, MN (United States). Dept. of Forest Resources; Ellsworth, D.S. [Brookhaven National Lab., Upton, NY (United States). Dept. of Applied Science; Walters, M.B. [Michigan State Univ., East Lansing, MI (United States). Dept. of Forestry; Vose, J.M. [Forest Service, Otto, NC (United States). Coweeta Hydrological Lab.; Gresham, C. [Clemson Univ., Georgetown, SC (United States). Baruch Forest Inst.; Volin, J.C. [Florida Atlantic Univ., Davie, FL (United States). Div. of Science; Bowman, W.D. [Inst. of Arctic and Alpine Research, Boulder, CO (United States). Mountain Research Station]|[Univ. of Colorado, Boulder, CO (United States). Dept. of Evolutionary, Population, and Organismic Biology
1999-09-01
Convergence in interspecific leaf trait relationships across diverse taxonomic groups and biomes would have important evolutionary and ecological implications. Such convergence has been hypothesized to result from trade-offs that limit the combination of plant traits for any species. Here the authors address this issue by testing for biome differences in the slope and intercept of interspecific relationships among leaf traits: longevity, net photosynthetic capacity (A{sub max}), leaf diffusive conductance (G{sub S}), specific leaf area (SLA), and nitrogen (N) status, for more than 100 species in six distinct biomes of the Americas. The six biomes were: alpine tundra-subalpine forest ecotone, cold temperate forest-prairie ecotone, montane cool temperate forest, desert shrubland, subtropical forest, and tropical rain forest. Despite large differences in climate and evolutionary history, in all biomes mass-based leaf N (N{sub mass}), SLA, G{sub S}, and A{sub max} were positively related to one another and decreased with increasing leaf life span. The relationships between pairs of leaf traits exhibited similar slopes among biomes, suggesting a predictable set of scaling relationships among key leaf morphological, chemical, and metabolic traits that are replicated globally among terrestrial ecosystems regardless of biome or vegetation type. However, the intercept (i.e., the overall elevation of regression lines) of relationships between pairs of leaf traits usually differed among biomes. With increasing aridity across sites, species had greater A{sub max} for a given level of G{sub S} and lower SLA for any given leaf life span. Using principal components analysis, most variation among species was explained by an axis related to mass-based leaf traits (A{sub max}, N, and SLA) while a second axis reflected climate, G{sub S}, and other area-based leaf traits.
Numerical Hydrodynamics in Strong-Field General Relativity
East, William Edward
In this thesis we develop and test methods for numerically evolving hydrodynamics coupled to the Einstein field equations, and then apply them to several problems in gravitational physics and astrophysics. The hydrodynamics scheme utilizes high-resolution shock-capturing techniques with flux corrections while the Einstein equations are evolved in the generalized harmonic formulation using finite difference methods. We construct initial data by solving the constraint equations using a multigrid algorithm with free data chosen based on superposing isolated compact objects. One application we consider is the merger of black hole-neutron star and neutron star-neutron star binaries that form through dynamical capture, as may occur in globular clusters or galactic nuclei. These systems can merge with non-negligible orbital eccentricity and display significant variability in dynamics and outcome as a function of initial impact parameter. We study the electromagnetic and gravitational-wave transients that these mergers may produce and their prospects for being detected with upcoming observations. We also introduce a numerical technique that allows solutions to the full Einstein equations to be obtained for extreme-mass-ratio systems where the spacetime is dominated by a known background solution. This technique is based on using the knowledge of a background solution to subtract off its contribution to the truncation error. We use this to study the tidal effects and gravitational radiation from a solar-type star falling into a supermassive black hole. Finally, we utilize general-relativistic hydrodynamics to study ultrarelativistic black hole formation. We study the head-on collision of fluid particles well within the kinetic energy dominated regime (Lorentz factors of 8-12). We find that black hole formation does occur at energies a factor of a few below simple hoop conjecture estimates. We also find that near the threshold for black hole formation, the collision leads to
Origins and development of the Cauchy problem in general relativity
Ringström, Hans
2015-06-01
The seminal work of Yvonne Choquet-Bruhat published in 1952 demonstrates that it is possible to formulate Einstein's equations as an initial value problem. The purpose of this article is to describe the background to and impact of this achievement, as well as the result itself. In some respects, the idea of viewing the field equations of general relativity as a system of evolution equations goes back to Einstein himself; in an argument justifying that gravitational waves propagate at the speed of light, Einstein used a special choice of coordinates to derive a system of wave equations for the linear perturbations on a Minkowski background. Over the following decades, Hilbert, de Donder, Lanczos, Darmois and many others worked to put Einstein's ideas on a more solid footing. In fact, the issue of local uniqueness (giving a rigorous justification for the statement that the speed of propagation of the gravitational field is bounded by that of light) was already settled in the 1930s by the work of Stellmacher. However, the first person to demonstrate both local existence and uniqueness in a setting in which the notion of finite speed of propagation makes sense was Yvonne Choquet-Bruhat. In this sense, her work lays the foundation for the formulation of Einstein's equations as an initial value problem. Following a description of the results of Choquet-Bruhat, we discuss the development of three research topics that have their origin in her work. The first one is local existence. One reason for addressing it is that it is at the heart of the original paper. Moreover, it is still an active and important research field, connected to the problem of characterizing the asymptotic behaviour of solutions that blow up in finite time. As a second topic, we turn to the questions of global uniqueness and strong cosmic censorship. These questions are of fundamental importance to anyone interested in justifying that the Cauchy problem makes sense globally. They are also closely
Fundamental Physics and General Relativity with the LARES and LAGEOS satellites
Energy Technology Data Exchange (ETDEWEB)
Ciufolini, Ignazio, E-mail: ignazio.ciufolini@unile.it [Dip. Ingegneria dell' Innovazione, Università del Salento, Lecce (Italy); Centro Fermi, Rome (Italy); Paolozzi, Antonio [Scuola di Ingegneria Aerospaziale, Sapienza Università di Roma (Italy); Koenig, Rolf [Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam (Germany); Pavlis, Erricos C. [Goddard Earth Science and Technology Center (GEST), University of Maryland, Baltimore County (United States); Ries, John [Center for Space Research, University of Texas at Austin (United States); Matzner, Richard [Center for Relativity, University of Texas at Austin (United States); Gurzadyan, Vahe [Center for Cosmology and Astrophysics, Alikhanian National Laboratory, Yerevan (Armenia); Penrose, Roger [Mathematical Institute, University of Oxford (United Kingdom); Sindoni, Giampiero; Paris, Claudio [Scuola di Ingegneria Aerospaziale, Sapienza Università di Roma (Italy)
2013-10-15
Current observations of the universe have strengthened the interest to further test General Relativity and other theories of fundamental physics. After an introduction to the phenomenon of frame-dragging predicted by Einstein's theory of General Relativity, with fundamental astrophysical applications to rotating black holes, we describe the past measurements of frame-dragging obtained by the LAGEOS satellites and by the dedicated Gravity Probe B space mission. We also discuss a test of String Theories of Chern-Simons type that has been carried out using the results of the LAGEOS satellites. We then describe the LARES space experiment. LARES was successfully launched in February 2012 to improve the accuracy of the tests of frame-dragging, it can also improve the test of String Theories. We present the results of the first few months of observations of LARES, its orbital analyses show that it has the best agreement of any other satellite with the test-particle motion predicted by General Relativity. We finally briefly report the accurate studies and the extensive simulations of the LARES space experiment, confirming an accuracy of a few percent in the forthcoming measurement of frame-dragging.
Reading Test-Taking Strategies in General Training IELTS
Nosrati, Vahede
2015-01-01
The significance of gaining a better understanding of how test-taking strategies are used has been recognized by researchers. Considering this fact, this study aimed at investigating the test-taking strategies which were employed by IELTS candidates in reading comprehension test. Besides, it tried to take into account the differences among…
Uniformly rotating, axisymmetric, and triaxial quark stars in general relativity
Zhou, Enping; Tsokaros, Antonios; Rezzolla, Luciano; Xu, Renxin; UryÅ«, KÅji
2018-01-01
Quasiequilibrium models of uniformly rotating axisymmetric and triaxial quark stars are computed in a general-relativistic gravity scenario. The Isenberg-Wilson-Mathews (IWM) formulation is employed and the Compact Object Calculator (cocal) code is extended to treat rotating stars with finite surface density and new equations of state (EOSs). Besides the MIT bag model for quark matter which is composed of deconfined quarks, we examine a new EOS proposed by Lai and Xu that is based on quark clustering and results in a stiff EOS that can support masses up to 3.3 M⊙ in the case we considered. We perform convergence tests for our new code to evaluate the effect of finite surface density in the accuracy of our solutions and construct sequences of solutions for both small and high compactness. The onset of secular instability due to viscous dissipation is identified and possible implications are discussed. An estimate of the gravitational wave amplitude and luminosity based on quadrupole formulas is presented and comparison with neutron stars is discussed.
Matzel, Louis D; Grossman, Henya; Light, Kenneth; Townsend, David; Kolata, Stefan
2008-10-01
A defining characteristic of age-related cognitive decline is a deficit in general cognitive performance. Here we use a testing and analysis regimen that allows us to characterize the general learning abilities of young (3-5 mo old) and aged (19-21 mo old) male and female Balb/C mice. Animals' performance was assessed on a battery of seven diverse learning tasks. Aged animals exhibited deficits in five of the seven tasks and ranked significantly lower than their young counterparts in general learning abilities (aggregate performance across the battery of tasks). Aging added variability to common core performance (i.e., general learning ability), which translated into increased variability on the individual cognitive tasks. Relatedly, general learning abilities did not differ between the two ages among the best quartile of learners (i.e., cognitive abilities were spared in a subsample of the aged animals). Additionally, working memory capacity (resistance to interference) and duration (resistance to decay) accounted for significantly more of the variability in general learning abilities in aged relative to young animals. Tests of 15 noncognitive performance variables indicated that an increase in body weight (and an associated decrease in general activity) was characteristic of those aged animals which exhibited deficient general learning abilities. These results suggest the possibility that general cognitive deficits in aged animals reflect a failure of specific components of the working memory system, and may be related to variations in body weight and an associated decrease in activity.
Confirmation of general relativity on large scales from weak lensing and galaxy velocities.
Reyes, Reinabelle; Mandelbaum, Rachel; Seljak, Uros; Baldauf, Tobias; Gunn, James E; Lombriser, Lucas; Smith, Robert E
2010-03-11
Although general relativity underlies modern cosmology, its applicability on cosmological length scales has yet to be stringently tested. Such a test has recently been proposed, using a quantity, E(G), that combines measures of large-scale gravitational lensing, galaxy clustering and structure growth rate. The combination is insensitive to 'galaxy bias' (the difference between the clustering of visible galaxies and invisible dark matter) and is thus robust to the uncertainty in this parameter. Modified theories of gravity generally predict values of E(G) different from the general relativistic prediction because, in these theories, the 'gravitational slip' (the difference between the two potentials that describe perturbations in the gravitational metric) is non-zero, which leads to changes in the growth of structure and the strength of the gravitational lensing effect. Here we report that E(G) = 0.39 +/- 0.06 on length scales of tens of megaparsecs, in agreement with the general relativistic prediction of E(G) approximately 0.4. The measured value excludes a model within the tensor-vector-scalar gravity theory, which modifies both Newtonian and Einstein gravity. However, the relatively large uncertainty still permits models within f(R) theory, which is an extension of general relativity. A fivefold decrease in uncertainty is needed to rule out these models.
Preferred Spatial Directions in the Universe: a General Relativity Approach
Directory of Open Access Journals (Sweden)
Borissova L.
2006-10-01
Full Text Available Herein is constructed, using General Relativity, the space metric along the Earth’s trajectory in the Galaxy, where the Earth traces outs a complicated spiral in its orbital motion around the Sun and its concomitant motion with the solar system around the centre of the Galaxy. It is deduced herein that this space is inhomogeneous and anisotropic. The observable properties of the space, characterizing its gravitation, rotation, deformation, and curvature, are obtained. The theory predicts that the observable velocity of light is anisotropic, due to the anisotropy and inhomogeneity of space caused by the presence of gravitation and the space rotation, despite the world-invariance of the velocity of light remaining unchanged. It is calculated that two pairs of synchronised clocks should record a different speed of light for light beams travelling towards the Sun and orthogonal to this direction, of about 4×10−4 c (i. e. 120 km/sec, 0.04% of the measured velocity of light c. This effect should have oscillations with a 12-hour period (due to the daily rotation of the Earth and 6 month period (due to the motion of the Earth around the Sun. The best equipment for detecting the effect is that being used by R. T. Cahill (Flinders University, Australia in his current experiments measuring the velocity of light in an RF coaxial-cable equipped with a pair of high precision synchronized Rb atomic clocks.
21 CFR 610.11a - Inactivated influenza vaccine, general safety test.
2010-04-01
... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Inactivated influenza vaccine, general safety test... Inactivated influenza vaccine, general safety test. For inactivated influenza vaccine, the general safety test... subcutaneous or intraperitoneal injection of 5.0 milliliters of inactivated influenza vaccine into each guinea...
Investigation of Response Changes in the GRE Revised General Test
Liu, Ou Lydia; Bridgeman, Brent; Gu, Lixiong; Xu, Jun; Kong, Nan
2015-01-01
Research on examinees' response changes on multiple-choice tests over the past 80 years has yielded some consistent findings, including that most examinees make score gains by changing answers. This study expands the research on response changes by focusing on a high-stakes admissions test--the Verbal Reasoning and Quantitative Reasoning measures…
General Atomics Smart Microsensors FY05 Shipboard Fire Test Results
2005-12-12
chloride, dimethyl methyl phosphonate and diisopropyl methyl phosphonate, and 2-chloroethyl ethyl sulfide were tested at 10, 25, 50, 100, and 200% of...1EST EST EST Test ID Location Description GA on Photo Multi 2 nd Deck-7 Spray Aerosol DNA ADN DNA DNA VS5_019 Ops-I 3 SCBA 1887 DNA DNA DNA 2nd Deck-9
Panaretos, John; Xekalaki, Evdokia
1986-01-01
The binomial and multinomial distributions are, probably, the best known distributions because of their vast number of applications. The present paper examines some generalizations of these distributions with many practical applications. Properties of these generalizations are studied and models giving rise to them are developed. Finally, their relationship to generalized Poisson distributions is examined and limiting cases are given
Smalley, L. L.
1983-01-01
The proper framework for testing Rastall's theory and its generalizations is in the case of non-negligible (i.e. discernible) gravitational effects such as gravity gradients. These theories have conserved integral four-momentum and angular momentum. The Nordtvedt effect then provides limits on the parameters which arise as the result of the non-zero divergence of the energy-momentum tensor.
Reading Test-taking Strategies in General Training IELTS
Directory of Open Access Journals (Sweden)
Vahede Nosrati
2015-10-01
Full Text Available The significance of gaining a better understanding of how test-taking strategies are used has been recognized by researchers. Considering this fact, this study aimed at investigating the test-taking strategies which were employed by IELTS candidates in reading comprehension test. Besides, it tried to take into account the differences among strategies used for different tasks. In order to gather data, two instruments were employed: the think-aloud protocol, and an IELTS reading test. The obtained data were analyzed and interpreted qualitatively by the researcher. The findings indicated that candidates employed 15 different strategies which were categorized in 3 stages, pre-reading, reading, and post-reading stages. Furthermore, it was revealed that test-takers used certain strategies differently, depending on the type of the task. The findings provide a better understanding of strategy use among IELTS candidates and help teachers to improve their approaches toward teaching and learning goals. Keywords: Test-taking Strategy, Test-taker, Reading Comprehension, Language Learning Strategy, IELTS
21 CFR 352.72 - General testing procedures.
2010-04-01
... sunscreen application shall be 2 milligrams per square centimeter. For oils and most lotions, the viscosity... noncompliant (e.g., subject withdraws from the test due to illness or work conflicts, subject does not shield...
General Evaluation Plan: Fleet Test and Evaluation Projects
Energy Technology Data Exchange (ETDEWEB)
2002-07-01
Document details the process used by the NREL Fleet Test & Evaluation team to choose the types of fleets, sites, and technologies they will evaluate. The National Renewable Energy Laboratory (NREL) Fleet Test & Evaluation (FT&E) team was formed to accomplish the objectives of U.S. Department of Energy's (DOE) current and emerging programs. Composed of NREL and Battelle personnel, the team supports vehicle test projects initiated by DOE's Office of FreedomCAR and Vehicle Technologies (OFCVT) and the Office of Hydrogen, Fuel Cells, and Infrastructure Technologies (OHFCIT). FT&E projects help fleet owners and operators facilitate purchase decisions by providing them with comprehensive laboratory and fleet test data on viable alternative fuel vehicles (AFVs) and advanced technology vehicles (ATVs). ATVs include hybrid electric and fuel cell vehicles.
Race Matters: The Relation between Race and General Campus Climate.
Reid, Landon D.; Radhakrishnan, Phanikiran
2003-01-01
Examines students' perceptions of racial and academic climate as possible mediators of racial differences in the perception of the university's general campus climate. Students evaluated their perceptions of racial, academic, and general campus climates. As expected, racial minority students, particularly African Americans, perceived more negative…
Hoehle, Lloyd P; Speth, Marlene M; Phillips, Katie M; Gaudin, Robert A; Caradonna, David S; Gray, Stacey T; Sedaghat, Ahmad R
2017-07-01
The impact of specific allergic rhinitis symptoms on patient quality of life (QOL) is currently unknown. In this study, we sought to determine the association between nasal and extranasal symptoms of allergic rhinitis with general health-related QOL. A total of 150 participants with ages > 18 years and persistent allergic rhinitis were prospectively recruited for this cross-sectional study. General health-related QOL was measured by using the visual analog scale (VAS) from the five-dimension EuroQol QOL survey (EQ-5D). The severity of nasal and extranasal symptoms was measured by using the 22-item Sino-Nasal Outcome Test (SNOT-22). The severity of nasal obstruction was measured by using the Nasal Obstruction Severity Evaluation (NOSE) scale. Each participant also completed a Rhinitis Control Assessment Test (RCAT). The total SNOT-22 score was significantly correlated with RCAT (r = -0.68 [95% confidence interval {CI}, -0.75 to -0.58]; p < 0.001) and EQ-5D VAS (r = -0.44 [95% CI, -0.56 to -0.30]; p < 0.001). Of the 22 symptoms assessed on the SNOT-22, sleep-related symptoms, and otologic symptoms were associated with the greatest decrease in general health-related QOL. Nasal symptoms were least associated with general health-related QOL. The symptom of nasal obstruction was not at all associated with general health-related QOL (p = 0.267). We confirmed this finding by showing no significant correlation between the NOSE score and EQ-5D VAS (r = -0.05 [95% CI, -0.21 to 0.12]; p = 0.582). Sleep and otologic symptoms were associated with the greatest negative impact on QOL in adults with persistent allergic rhinitis and should be routinely assessed in their clinical evaluation.
Disseminating General Relativity for 21st century astronomy
Crosta, Mariateresa
2015-08-01
The talk aims to present two outreach projects - initially developed for the ESA Gaia satellite, a multidisciplinary mission launched on December 19, 2013 - available to the OAD community: NeST and "The Meaning of Light".NeST is an interactive educational tool, that displays how the theory of GR rules the Universe, it creates a performance physically "belonging" to the exhibition space and moving through it, materializing what J.A. Wheeler said "mass tells space-time how to curve, and space-time tells mass how to move"."The Meaning of Light" is a short motion comics, part of an extensive outreach program called "The History of Photons" whose main theme is the story of a beam of stellar photons that, after leaving the progenitor star, propagates through the Universe and, once intercepted come into contact with a team of scientists: here begins their adventure to be taken "back" home and in doing so the scientists, and the spectators, are driven to discover the wonders of which the light are the bearers.The description of the journey of the photons becomes, therefore, an opportunity to easily tell the fascinating topics of Astrophysics and General Relativity, i.e. the complexity and the infinite beauty of the Universe in which we live.For this movie a new theme song was produced, "Singing the Stars", whose refrain (Oh Be A Fine Girl / Guy Kiss Me Little Thing, Yeah) adds to the famous mnemonic for stellar classification (OBAFGKM) the new stellar types LTY discovered in recent years.
Some General Principles in Cryogenic Design, Implementation, and Testing
Dipirro, Michael James
2015-01-01
Brief Course Description: In 2 hours only the most basic principles of cryogenics can be presented. I will concentrate on the differences between a room temperature thermal analysis and cryogenic thermal analysis, namely temperature dependent properties. I will talk about practical materials for thermal contact and isolation. I will finish by describing the verification process and instrumentation used that is unique to cryogenic (in general less than 100K) systems.
Gravitational wave astronomy, relativity tests, and massive black holes
Bender, Peter L.; Bender
2010-01-01
The gravitational wave detectors that are operating now are looking for several kinds of gravitational wave signals at frequencies of tens of Hertz to kilohertz. One of these is mergers of roughly 10 M⊙ BH binaries. Sometime between now and about 8 years from now, it is likely that signals of this kind will be observed. The result will be strong tests of the dynamical predictions of general relativity in the high field regime. However, observations at frequencies below 1 Hz will have to wait until the launch of the Laser Interferometer Space Antenna (LISA), hopefully only a few years later. LISA will have 3 main objectives, all involving massive BHs. The first is observations of mergers of pairs of intermediate mass (100 to 105 M⊙) and higher mass BHs at redshifts out to roughly z=10. This will provide new information on the initial formation and growth of BHs such as those found in most galaxies, and the relation between BH growth and the evolution of galactic structure. The second objective is observations of roughly 10 M⊙ BHs, neutron stars, and white dwarfs spiraling into much more massive BHs in galactic nuclei. Such events will provide detailed information on the populations of such compact objects in the regions around galactic centers. And the third objective is the use of the first two types of observations for testing general relativity even more strongly than ground based detectors will. As an example, an extreme mass ratio event such as a 10 M⊙ BH spiraling into a galactic center BH can give roughly 105 observable cycles during about the last year before merger, with a mean relative velocity of 1/3 to 1/2 the speed of light, and the frequencies of periapsis precession and Lense-Thirring precession will be high. The LISA Pathfinder mission to prepare for LISA is scheduled for launch in 2011.
40 CFR 86.1330-90 - Test sequence; general requirements.
2010-07-01
... control devices which sense or detect ambient air temperature and operate at 68 °F or higher, the test... that particular engine. (ii) Inlet depression and exhaust backpressure shall be set with the engine operating at rated speed and wide open throttle, except for the case of inlet depression for naturally...
A sequential hypothesis test based on a generalized Azuma inequality
Reijsbergen, D.P.; Scheinhardt, Willem R.W.; de Boer, Pieter-Tjerk
We present a new power-one sequential hypothesis test based on a bound for the probability that a bounded zero-mean martingale ever crosses a curve of the form $a(n+k)^b$. The proof of the bound is of independent interest.
16 CFR 1211.5 - General testing parameters.
2010-01-01
... § 1211.15(i) and (k). (7) When the Demonstrated Method Test is conducted, the multiplier is to be based... condition flow chart shown in figure 1 shall be used: (1) To conduct a failure-mode and effect analysis...
40 CFR 86.1773-99 - Test sequence; general requirements.
2010-07-01
... category (e.g., TLEV, LEV, ULEV); (v) Fuel type (e.g., gasoline, methanol, etc.). (4) The same engine... vehicle shall be approximately level during all phases of the test sequence to prevent abnormal fuel...) which are representative of the array of technologies available in that model year. Only TLEVs, LEVs...
Generalized Reduced Rank Tests using the Singular Value Decomposition
Kleibergen, F.R.; Paap, R.
2006-01-01
We propose a novel statistic to test the rank of a matrix. The rank statistic overcomes deficiencies of existing rank statistics, like: a Kronecker covariance matrix for the canonical correlation rank statistic of Anderson [Annals of Mathematical Statistics (1951), 22, 327-351] sensitivity to the
Testing for one Generalized Linear Single Order Parameter
DEFF Research Database (Denmark)
Ellegaard, Niels Langager; Christensen, Tage Emil; Dyre, Jeppe
We examine a linear single order parameter model for thermoviscoelastic relaxation in viscous liquids, allowing for a distribution of relaxation times. In this model the relaxation of volume and entalpy is completely described by the relaxation of one internal order parameter. In contrast to prior...... work the order parameter may be chosen to have a non-exponential relaxation. The model predictions contradict the general consensus of the properties of viscous liquids in two ways: (i) The model predicts that following a linear isobaric temperature step, the normalized volume and entalpy relaxation...
Standard Penetration Test and Relative Density
1971-02-01
La Prueba Normal de Penetraciocn y la Densidad Relativa K.-J. Melzer PhD, Research Engineer U. S. Army Engineer Waterways Experiment Station Vicksburg...en la prueba normal de penetraci’n (Standard Penetration Test) de una arena bajo el nivel freatico y el correspond- iente numero en una arena seca (ie...de laboratorio ejecutados con un penetr6metro est’tico pequeno. INTRODUCTION One of the main problems encountered in subsoil e’xploration is in situ
General Safety and Waste Management Related to SAM
The General Safety and Waste Management page offers section-specific safety and waste management details for chemicals, radiochemicals, pathogens, and biotoxins included in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).
Emotion perception and empathy: An individual differences test of relations.
Olderbak, Sally; Wilhelm, Oliver
2017-10-01
Numerous theories posit a positive relation between perceiving emotion expressed in the face of a stranger (emotion perception) and feeling or cognitively understanding the emotion of that person (affective and cognitive empathy, respectively). However, when relating individual differences in emotion perception with individual differences in affective or cognitive empathy, effect sizes are contradictory, but often not significantly different from zero. Based on 4 studies (study ns range from 97 to 486 persons; n total = 958) that differ from one another on many design and sample characteristics, applying advanced modeling techniques to control for measurement error, we estimate relations between affective empathy, cognitive empathy, and emotion perception. Relations are tested separately for each of the 6 basic emotions (an emotion-specific model) as well as across all emotions (an emotion-general model). Reflecting the literature, effect sizes and statistical significance with an emotion-general model vary across the individual studies (rs range from -.001 to .24 for emotion perception with affective empathy and -.01 to .39 for emotion perception with cognitive empathy), with a meta-analysis of these results indicating emotion perception is weakly related with affective (r = .13, p = .003) and cognitive empathy (r = .13, p = .05). Relations are not strengthened in an emotion-specific model. We argue that the weak effect sizes and inconsistency across studies reflects a neglected distinction of measurement approach-specifically, empathy is assessed as typical behavior and emotion perception is assessed as maximal effort-and conclude with considerations regarding the measurement of each construct. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Confidence intervals for test information and relative efficiency
Oosterloo, Sebe J.
1984-01-01
In latent theory the measurement properties of a mental test can be expressed in the test information function. The relative merits of two tests for the same latent trait can be described by the relative efficiency function, i.e. the ratio of the test information functions. It is argued that these
HIV-Related Risk Behaviors Among Labor Migrants, Their Wives and the General Population in Nepal.
Thapa, Subash; Thapa, Deependra Kaji; Buve, Anne; Hannes, Karin; Nepal, Chiranjibi; Mathei, Catharina
2017-04-01
Nepalese labor migrants and their wives are considered as at-risk populations for HIV infection. There may be a risk of HIV transmission from the labor migrant and their wives to the general population due to HIV-related risk behaviors, but so far empirical evidence to support this hypothesis is scarce. Therefore, this study was conducted to compare HIV-related risk behaviors between labor migrants, their wives, and males and females from the general population in the far-western region of Nepal. This was a cross-sectional study, in which structured face-to-face interviews were conducted with 261 male labor migrants, 262 wives of labor migrants, 123 males and 122 females from the general population. We found that the proportion of the labor migrants and their wives reporting having had extramarital sex in the previous year did not differ significantly with the males (11.9 vs. 13.4 %, p value 0.752) and females (2.0 vs. 1.7 %, p value 0.127) from the general population. However, the labor migrants compared with the males from the general population were 1.51 times and the wives of labor migrants compared with the females from the general population were 2.37 times more likely to have been tested for HIV. Both the males from the general population and the labor migrants are equally engaged in unprotected extramarital sex. Therefore, it is recommended that the prevention programs, including access to condoms and HIV testing, should be scaled up targeting a broader range of individuals in the far-western region of Nepal.
2010-10-01
... testing; cytology general supervisor. 493.1467 Section 493.1467 Public Health CENTERS FOR MEDICARE....1467 Condition: Laboratories performing high complexity testing; cytology general supervisor. For the subspecialty of cytology, the laboratory must have a general supervisor who meets the qualification...
Lake, Kayll
2010-12-01
, Hoenselaers C and Herlt E 2003 Exact Solutions of Einstein's Field Equations (Second Edition) (Cambridge: Cambridge University Press) [2] Pretorius F and Israel W 1998 Class. Quantum Grav.15 2289 [3] Wiltshire D, Visser M and Scott S (ed) 2008 The Kerr Spacetime: Rotating Black Holes in General Relativity (Cambridge: Cambridge University Press) [4] Coley A, Hervik S and Pelavas N 2009 Class. Quantum Grav. 26 025013 [5] Plebański J and Krasiński A 2006 An Introduction to General Relativity and Cosmology (Cambridge: Cambridge University Press)
Entropic uncertainty relation based on generalized uncertainty principle
Hsu, Li-Yi; Kawamoto, Shoichi; Wen, Wen-Yu
2017-09-01
We explore the modification of the entropic formulation of uncertainty principle in quantum mechanics which measures the incompatibility of measurements in terms of Shannon entropy. The deformation in question is the type so-called generalized uncertainty principle that is motivated by thought experiments in quantum gravity and string theory and is characterized by a parameter of Planck scale. The corrections are evaluated for small deformation parameters by use of the Gaussian wave function and numerical calculation. As the generalized uncertainty principle has proven to be useful in the study of the quantum nature of black holes, this study would be a step toward introducing an information theory viewpoint to black hole physics.
Roca-Varela, Mª Luisa; Palacios, Ignacio M.
2013-01-01
This paper examines some of the best known proficiency tests in English, with particular focus on the oral component. Attention is paid to the following issues, among others: the weighting of oral elements in testing, the criteria used for the assessment of oral skills and the relation of these to the general guidelines in the "Common…
Scheel, Benedicte Iversen; Holtedahl, Knut
2015-01-01
To study the relative importance of different tools a GP can use during the diagnostic process towards cancer detection. Retrospective cohort study with prospective registration of cancer in general practice. One hundred and fifty-seven Norwegian general practitioners (GPs) reported 261 cancer patients. During 10 consecutive days, GPs registered all patient consultations and recorded any presence of seven focal symptoms and three general symptoms, commonly considered as warning signs of cancer (WSC). Follow-up was done six to 11 months later. For each patient with new or recurrent cancer, the GP completed a questionnaire with medical-record-based information concerning the diagnostic procedure. In 78% of cancer cases, symptoms, signs, or tests helped diagnose cancer. In 90 cases, there were 131 consultation-recorded WSC that seemed related to the cancer. Further symptoms were reported for another 74 cases. Different clinical signs were noted in 41 patients, 16 of whom had no previous recording of symptoms. Supplementary tests added information in 59 cases; in 25 of these there were no recordings of symptoms or signs. Sensitivity of any cancer-relevant symptom or clinical finding ranged from 100% for patients with uterine body cancer to 57% for patients with renal cancer. WSC had a major role as initiator of a cancer diagnostic procedure. Low-risk-but-not-no-risk symptoms also played an important role, and in 7% of patients they were the only symptoms. Clinical findings and/or supplementary procedures were sometimes decisive for rapid referral.
General fuel cell hybrid synergies and hybrid system testing status
Winkler, Wolfgang; Nehter, Pedro; Williams, Mark C.; Tucker, David; Gemmen, Randy
FCT hybrid power systems offer the highest efficiency and the cleanest emissions of all fossil fuelled power. The engineering for the highest possible efficiency at lowest cost and weight depends on general system architecture issues and the performance of the components. Presented in this paper are system studies which provide direction for the most efficient path toward achieving the most beneficial result for this technology. Ultimately, fuel cell-turbine (FCT) hybrid systems applicable to integrated gasification combined cycle power systems will form the basis for reaching the goals for advanced coal-based power generation. The FCT hybrid power island will also be important for the FutureGen plant and will provide new options for carbon dioxide capture and sequestration as well as power and hydrogen generation. The system studies presented in this paper provide insight to current technology 'benchmarks' versus expected benefits from hybrid applications. Discussion is also presented on the effects of different balance of plant arrangements and approaches. Finally, we discuss the status of US DOE is sponsored projects that are looking to help understand the unique requirements for these systems. One of these projects, Hyper, will provide information on FCT dynamics and will help identify technical needs and opportunities for cycle advancement. The methods studied show promise for effective control of a hybrid system without the direct intervention of isolation valves or check valves in the main pressure loop of the system, which introduce substantial pressure losses, allowing for realization of the full potential efficiency of the hybrid system.
Personality Factors Related to Career Satisfaction among General Practitioners.
Schwartz, Robert H.; Shenoy, Sunil
1994-01-01
A survey of 150 general practice dentists examined the relationship between 6 career interests (scientific, artistic, social, enterprising, conventional, technical) and career satisfaction. Results are presented and compared with findings of other studies of dental students and practitioners. Results suggest that satisfied dentists tended to like…
Cooperative Work Education in Diversified Occupations. General Related Curriculum Guide.
Brysgel, David
This guide is intended as a working document for coordinators of cooperative work education in diversified occupations. It contains materials for use in providing students with general classroom instruction concurrent with on-the-job training. The following topics are covered in the individual units in the first-year curriculum: the cooperative…
Einstein's Unification: General Relativity and the Quest for Mathematical Naturalness
van Dongen, J.A.E.F.
2002-01-01
The aim of the thesis has been to understand Einstein's development and see the historical coherence in his later attitude in physics. The lesson we learned has been straightforward: the key that unlocks the later Einstein lies in the road by which he arrived at the field equations of general
A chiral alternative to the vierbein field in general relativity
Hooft, G. 't
1991-01-01
An alternative to the usual vierbein field in a (3 + 1)-dimensional (euclidean) space-time is proposed such that the internal index takes only three values and the external is a double: ea = −ea. In flat space-time this field reduces to the self-dual generalized Levi-Civita symbol a. Like the
Fundamental optimal relation of a generalized irreversible Carnot ...
Indian Academy of Sciences (India)
The effects of heat transfer laws and various loss terms are analysed. The heating load vs. COP characteristic of a generalized irreversible Carnot heat pump is a parabolic-like curve, which is consistent with the experimental result of thermoelectric heat pump. The obtained results include those obtained in many literatures ...
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Nys, S.; Merode, T. van; Bartelds, A.I.M.; Stobberingh, E.E.
2006-01-01
Objectives: Urinary tract infections (UTIs) are common bacterial infections encountered in general practice. For the optimal treatment the general practitioner (GP) should rely on the results of diagnostic tests and recent antimicrobial susceptibility of uropathogens. Patients and methods: In total
A General Asymptotic Framework for Distribution-Free Graph-Based Two-Sample Tests
Bhattacharya, Bhaswar B.
2015-01-01
Testing equality of two multivariate distributions is a classical problem for which many non-parametric tests have been proposed over the years. Most of the popular two-sample tests, which are asymptotically distribution-free, are based either on geometric graphs constructed using inter-point distances between the observations (multivariate generalizations of the Wald-Wolfowitz's runs test) or on multivariate data-depth (generalizations of the Mann-Whitney rank test). This paper introduces a ...
Dai, James Y.; Chan, Kwun Chuen Gary; Hsu, Li
2014-01-01
Instrumental variable regression is one way to overcome unmeasured confounding and estimate causal effect in observational studies. Built on structural mean models, there has been considerale work recently developed for consistent estimation of causal relative risk and causal odds ratio. Such models can sometimes suffer from identification issues for weak instruments. This hampered the applicability of Mendelian randomization analysis in genetic epidemiology. When there are multiple genetic variants available as instrumental variables, and causal effect is defined in a generalized linear model in the presence of unmeasured confounders, we propose to test concordance between instrumental variable effects on the intermediate exposure and instrumental variable effects on the disease outcome, as a means to test the causal effect. We show that a class of generalized least squares estimators provide valid and consistent tests of causality. For causal effect of a continuous exposure on a dichotomous outcome in logistic models, the proposed estimators are shown to be asymptotically conservative. When the disease outcome is rare, such estimators are consistent due to the log-linear approximation of the logistic function. Optimality of such estimators relative to the well-known two-stage least squares estimator and the double-logistic structural mean model is further discussed. PMID:24863158
Quasinormal modes as a distinguisher between general relativity and f (R ) gravity
Bhattacharyya, Soham; Shankaranarayanan, S.
2017-09-01
Quasinormal modes (QNMs) or the ringdown phase of gravitational waves provide critical information about the structure of compact objects like black holes. Thus, QNMs can be a tool to test general relativity (GR) and possible deviations from it. In the case of GR, it has been known for a long time that a relation between two types of black hole perturbations—scalar (Zerilli) and vector (Regge-Wheeler)—leads to an equal share of emitted gravitational energy. With the direct detection of gravitational waves, it is now natural to ask whether the same relation (between scalar and vector perturbations) holds for modified gravity theories, and if not, whether one can use this as a way to probe deviations from general relativity. As a first step, we show explicitly that the above relation between Regge-Wheeler and Zerilli perturbations breaks down for a general f (R ) model and hence the two perturbations do not share equal amounts of emitted gravitational energy. We discuss the implication of this imbalance for observations and the no-hair conjecture.
Directory of Open Access Journals (Sweden)
Eldesoky E. Afify
2013-05-01
Full Text Available In this article, some recurrence relations of inverse and ratio moments for generalized order statistics from doubly truncated and non-truncated generalized exponential distribution are derived. From our results, we deduce the recurrence relations for single and product moments of generalized order statistics from general class distribution obtained by Haseeb and Hassan (2004, also we deduce the recurrence relations for single and product moments of order statistics from generalized exponential distribution obtained by Saran and Pushkarna (2000.
Momentum in General Relativity: Local versus Quasilocal Conservation Laws
Epp, Richard J; Mann, Robert B
2013-01-01
We construct a general relativistic conservation law for linear and angular momentum for matter and gravitational fields in a finite volume of space that does not rely on any spacetime symmetries. This work builds on our previous construction of a general relativistic energy conservation law with the same features. Our approach uses the Brown and York quasilocal stress-energy-momentum tensor for matter and gravitational fields, plus the concept of a rigid quasilocal frame (RQF) introduced in previous work. The RQF approach allows us to construct, in a generic spacetime, frames of reference whose boundaries are rigid (their shape and size do not change with time), and that have precisely the same six arbitrary time-dependent degrees of freedom as the accelerating and tumbling rigid frames we are familiar with in Newtonian mechanics. These RQFs, in turn, give rise to a completely general conservation law for the six components of momentum (three linear and three angular) of a finite system of matter and gravita...
Preservation of FFTF Data Related to Passive Safety Testing
Energy Technology Data Exchange (ETDEWEB)
Wootan, David W.; Butner, R. Scott; Omberg, Ronald P.; Makenas, Bruce J.; Nielsen, Deborah L.
2010-10-01
experience to a large-size LMR and obtain data for validating design analysis computer codes, and 3) to develop and test passive safety enhancements that might be used for future LMRs. These tests were designed to provide data sufficient to allow separation of fuel temperature effects from structural temperature effects. The data developed through this testing program were used to verify the predictive capability of passive safety analysis methods as well as provide a data base for calibrating design tools such as the SASSYS/SAS4A codes. These tests were instrumental in improving understanding of reactivity feedback mechanisms in LMRs and demonstrating passive safety margins available in an LMR. Knowledge preservation at the FFTF is focused on the areas of design, construction, startup, and operation of the reactor. This information may be of potential use for international exchanges with other LMR programs around the world. This information provides the basis for creating benchmarks for validating and testing large scale computer programs. All information preserved to date is now being stored and categorized consistent with the IAEA international standardized taxonomy. The test results information exists in several different formats depending upon the final stage of the test evaluation. Over 100 documents relevant to passive safety testing have been identified and are being recovered, scanned, and catalogued. Attempts to recover plant data tapes are also in progress. Documents related to passive safety testing are now being categorized consistent with internationally agreed upon IAEA standards. Documents are being converted to electronic format compatible with a general search engine being developed by INL. The data from the FFTF passive safety tests provides experimental verification of structural reactivity effects that should be very useful to innovative designers seeking to optimize passive safety in the design of new LMRs.
Nonextensive kinetic theory and H-theorem in general relativity
Santos, A. P.; Silva, R.; Alcaniz, J. S.; Lima, J. A. S.
2017-11-01
The nonextensive kinetic theory for degenerate quantum gases is discussed in the general relativistic framework. By incorporating nonadditive modifications in the collisional term of the relativistic Boltzmann equation and entropy current, it is shown that Tsallis entropic framework satisfies a H-theorem in the presence of gravitational fields. Consistency with the 2nd law of thermodynamics is obtained only whether the entropic q-parameter lies in the interval q ∈ [ 0 , 2 ] . As occurs in the absence of gravitational fields, it is also proved that the local collisional equilibrium is described by the extended Bose-Einstein (Fermi-Dirac) q-distributions.
Test-Retest Changes on Scholastic Aptitude Tests Are Not Related to "g"
Coyle, Thomas R.
2006-01-01
This research examined the relation between test-retest changes on scholastic aptitude tests and g-loaded cognitive measures (viz., college grade-point average, Wonderlic Personnel Test, and word recall). University students who had twice taken a scholastic aptitude test (viz., Scholastic Assessment Test or American College Testing Program…
General Theory of Relativity - The Power of Speculative Thought
Indian Academy of Sciences (India)
esting document revealing the thoughts and feelings of the great scientist about the beginning of GTR. Einstein wri tes - "Then there occurred to me .... the happiest thought of my life, in the following form. The gravita- tional field has only a relative existence in a very similar. Asit Banerjee retired from. Jadavpur University as a.
A generalized relative total variation method for image smoothing
Liu, Qiegen; Xiong, Biao; Yang, Dingcheng; Zhang, Minghui
2016-01-01
Recently, two piecewise smooth models L0smoothing and relative total variation (RTV) have been proposed for feature/structure-preserving filtering. One is very efficient for tackling image with little texture patterns and the other has appearance performance on image with abundant uniform textural
Special relativity in general frames from particles to astrophysics
Gourgoulhon, Éric
2013-01-01
Special relativity is the basis of many fields in modern physics: particle physics, quantum field theory, high-energy astrophysics, etc. This theory is presented here by adopting a four-dimensional point of view from the start. An outstanding feature of the book is that it doesn’t restrict itself to inertial frames but considers accelerated and rotating observers. It is thus possible to treat physical effects such as the Thomas precession or the Sagnac effect in a simple yet precise manner. In the final chapters, more advanced topics like tensorial fields in spacetime, exterior calculus and relativistic hydrodynamics are addressed. In the last, brief chapter the author gives a preview of gravity and shows where it becomes incompatible with Minkowsky spacetime. Well illustrated and enriched by many historical notes, this book also presents many applications of special relativity, ranging from particle physics (accelerators, particle collisions, quark-gluon plasma) to astrophysics (relativistic jets, active g...
General Relativity eliminates Dark Energy, Dark Matter and Universal Expansion
Bartlett, Rodney
2018-01-01
This letter was rejected by International Knowledge Press because "we are unable to conclude that these findings would warrant publication in this journal." The letter is suggesting that dark energy, dark matter and universal expansion are intimately related. However, they aren't viewed as revolutions in cosmology which are essential to a complete understanding of the modern universe. They are instead viewed as properties which need to be added to the cosmos when Einstein...
General characteristics of relative dispersion in the ocean
Corrado, Raffaele; Lacorata, Guglielmo; Palatella, Luigi; Santoleri, Rosalia; Zambianchi, Enrico
2017-04-01
The multi-scale and nonlinear nature of the ocean dynamics dramatically affects the spreading of matter, like pollutants, marine litter, etc., of physical and chemical seawater properties, and the biological connectivity inside and among different basins. Based on the Finite-Scale Lyapunov Exponent analysis of the largest available near-surface Lagrangian data set from the Global Drifter Program, our results show that, despite the large variety of flow features, relative dispersion can ultimately be described by a few parameters common to all ocean sub-basins, at least in terms of order of magnitude. This provides valuable information to undertake Lagrangian dispersion studies by means of models and/or of observational data. Moreover, our results show that the relative dispersion rates measured at submesoscale are significantly higher than for large-scale dynamics. Auxiliary analysis of high resolution GPS-tracked drifter hourly data as well as of the drogued/undrogued status of the buoys is provided in support of our conclusions. A possible application of our study, concerning reverse drifter motion and error growth analysis, is proposed relatively to the case of the missing Malaysia Airlines MH370 aircraft.
Directory of Open Access Journals (Sweden)
maryam Heydarpour Meymeh
2009-03-01
Full Text Available Background and purpose: Multiple choice tests are the most common type of tests used in evaluating the general English knowledge of the students in most medical universities, however the efficacy of these tests are not examined precisely. Wecompare and examine the integrative tests and discrete point tests as measures of the English language knowledge of medical students.Methods: Three tests were given to 60 undergraduate physiotherapy and Audiology students in their second year of study (after passing their general English course. They were divided into 2 groups.The first test for both groups was an integrative test, writing. The second test was a multiple - choice test 0.(prepositions for group one and a multiple - choice test of tensesfor group two. The same items which were mostfi-equently used wrongly in thefirst test were used in the items of the second test. A third test, a TOEFL, was given to the subjects in order to estimate the correlation between this test and tests one and two.Results: The students performed better in the second test, discrete point test rather than the first which was an integrative test. The same grammatical mistakes in the composition were used correctly in the multiple choice tests by the students.Conclusion:Our findings show that student perform better in non-productive rather than productive test. Since being competent English language user is an expected outcome of university language courses it seems warranted to switch to integrative tests as a measure of English language competency.Keywords: INTEGRATIVE TESTS, ENGLISH LANGUAGE FOR MEDICINE, ACADEMIC ENGLISH
Maladaptive Core Beliefs and their Relation to Generalized Anxiety Disorder.
Koerner, Naomi; Tallon, Kathleen; Kusec, Andrea
2015-01-01
Research has demonstrated that individuals with generalized anxiety disorder (GAD) hold unhelpful beliefs about worry, uncertainty, and the problem-solving process. Extant writings (e.g., treatment manuals) also suggest that other types of maladaptive beliefs may characterize those with GAD. However, these other beliefs have received limited empirical attention and are not an explicit component of cognitive theories of GAD. The present study examined the extent to which dysfunctional attitudes, early maladaptive schemas, and broad self-focused and other-focused beliefs explain significant variance in GAD symptoms, over and above negative and positive beliefs about worry, negative beliefs about uncertainty, and negative beliefs about problems. N = 138 participants classified into Probable GAD and Non-GAD groups completed self-report measures. After controlling for trait anxiety and depressive symptoms, only beliefs about worry, negative beliefs about uncertainty, and schemas reflecting unrelenting standards (e.g., "I must meet all my responsibilities all the time"), the need to self-sacrifice (e.g., "I'm the one who takes care of others"), and less positive views of other people and their intentions (e.g., lower endorsement of views such as "other people are fair"), were unique correlates of Probable GAD versus Non-GAD or GAD severity. Theoretical and clinical implications are discussed.
Timing and General Relativity in the Double Pulsar System
Kramer, Michael
2018-01-01
Radio astronomy provides a unique tool for probing strong-field gravity. The best example is given by the Double Pulsar system, where two active pulsars orbit each other in less than 2.5 h. This talk will present the latest results on the system, including the detection of new relativistic effects. It will also give an outlook onto the measurements of the moment-of-inertia of a neutron star. Given that the system also provides the most precise measurement of gravitational wave emission, it is also timely to compare the tests possible with the system today to current and future results of AdvLIGO, demonstrating that both methods complement each other in an almost ideal scenario.
Hong, Eunsook; Peng, Yun; O'Neil, Harold F., Jr.; Wu, Junbin
2013-01-01
The study examined the effects of gender and item content of domain-general and domain-specific creative-thinking tests on four subscale scores of creative-thinking (fluency, flexibility, originality, and elaboration). Chinese tenth-grade students (234 males and 244 females) participated in the study. Domain-general creative thinking was measured…
Multifractal spectrum of phase space related to generalized thermostatistics
Olemskoi, A. I.; Kharchenko, V. O.; Borisyuk, V. N.
2008-03-01
We consider a self-similar phase space with specific fractal dimension d being distributed with spectrum function f(d) . Related thermostatistics is shown to be governed by the Tsallis formalism of the non-extensive statistics, where the non-additivity parameter equals to τ ¯ (q) ≡ 1 / τ(q) > 1, and the multifractal function τ(q) = qdq - f(dq) is the specific heat determined with multifractal parameter q ∈ [ 1 , ∞ ] . At that, the equipartition law is shown to take place. Optimization of the multifractal spectrum function f(d) arrives at the relation between the statistical weight and the system complexity. It is shown that the statistical weight exponent τ(q) can be modeled by hyperbolic tangent deformed in accordance with both Tsallis and Kaniadakis exponential functions to describe arbitrary multifractal phase space explicitly. The spectrum function f(d) is proved to increase monotonically from minimum value f = - 1 at d = 0 to maximum one f = 1 at d = 1. At the same time, the number of monofractals increases with the growth of the phase-space volume at small dimensions d and falls down in the limit d → 1.
Extension of relational event algebra to a general decision making setting
Energy Technology Data Exchange (ETDEWEB)
Goodman, I.R.; Kramer, G.F.
1996-12-31
Relational Event Algebra (REA) is a new mathematical tool which provides an explicit algebraic reconstruction of events (appropriately designated as relational events) when initially only the formal probability values of such events are given as functions of known contributing event probabilities. In turn, once such relational events are obtained, one can then determine the probability of any finite logical combination, and in particular, various probabilistic distance measures among the events. A basic application of REA is to test hypotheses for the similarity of distinct models attempting to describe the same events such as in data fusion and combination of evidence. This paper considers new motivation for the use of REA, as well as a more general decision-making framework where system performance and redundancy / consistency tradeoffs are considered.
Modeling of charged anisotropic compact stars in general relativity
Energy Technology Data Exchange (ETDEWEB)
Dayanandan, Baiju; Maurya, S.K.; T, Smitha T. [University of Nizwa, Department of Mathematical and Physical Sciences, College of Arts and Science, Nizwa (Oman)
2017-06-15
A charged compact star model has been determined for anisotropic fluid distribution. We have solved the Einstein-Maxwell field equations to construct the charged compact star model by using the radial pressure, the metric function e{sup λ} and the electric charge function. The generic charged anisotropic solution is verified by exploring different physical conditions like causality condition, mass-radius relation and stability of the solution (via the adiabatic index, TOV equations and the Herrera cracking concept). It is observed that the present charged anisotropic compact star model is compatible with the star PSR 1937+21. Moreover, we also presented the EOS ρ = f(p) for the present charged compact star model. (orig.)
29 CFR 541.201 - Directly related to management or general business operations.
2010-07-01
... 29 Labor 3 2010-07-01 2010-07-01 false Directly related to management or general business... management or general business operations. (a) To qualify for the administrative exemption, an employee's primary duty must be the performance of work directly related to the management or general business...
Generality of a congruity effect in judgements of relative order.
Liu, Yang S; Chan, Michelle; Caplan, Jeremy B
2014-10-01
The judgement of relative order (JOR) procedure is used to investigate serial-order memory. Measuring response times, the wording of the instructions (whether the earlier or the later item was designated as the target) reversed the direction of search in subspan lists (Chan, Ross, Earle, & Caplan Psychonomic Bulletin & Review, 16(5), 945-951, 2009). If a similar congruity effect applied to above-span lists and, furthermore, with error rate as the measure, this could suggest how to model order memory across scales. Participants performed JORs on lists of nouns (Experiment 1: list lengths = 4, 6, 8, 10) or consonants (Experiment 2: list lengths = 4, 8). In addition to the usual distance, primacy, and recency effects, instructions interacted with serial position of the later probe in both experiments, not only in response time, but also in error rate, suggesting that availability, not just accessibility, is affected by instructions. The congruity effect challenges current memory models. We fitted Hacker's (Journal of Experimental Psychology: Human Learning and Memory, 6(6), 651-675, 1980) self-terminating search model to our data and found that a switch in search direction could explain the congruity effect for short lists, but not longer lists. This suggests that JORs may need to be understood via direct-access models, adapted to produce a congruity effect, or a mix of mechanisms.
Generalized fluctuation relation for power-law distributions
Budini, Adrián A.
2012-07-01
Strong violations of existing fluctuation theorems may arise in nonequilibrium steady states characterized by distributions with power-law tails. The ratio of the probabilities of positive and negative fluctuations of equal magnitude behaves in an anomalous nonmonotonic way [H. Touchette and E. G. D. Cohen, Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.76.020101 76, 020101(R) (2007)]. Here, we propose an alternative definition of fluctuation relation (FR) symmetry that, in the power-law regime, is characterized by a monotonic linear behavior. The proposal is consistent with a large deviationlike principle. As an example, we study the fluctuations of the work done on a dragged particle immersed in a complex environment able to induce power-law tails. When the environment is characterized by spatiotemporal temperature fluctuations, distributions arising in nonextensive statistical mechanics define the work statistics. In that situation, we find that the FR symmetry is solely defined by the average bath temperature. The case of a dragged particle subjected to a Lévy noise is also analyzed in detail.
Solution of Supplee's submarine paradox through special and general relativity
Vieira, R S
2016-01-01
In 1989 Supplee described an apparent relativistic paradox on which a submarine seems to sink in a given frame while floating in another one. If the submarine density is adjusted to be the same as the water density (when both of them are at rest) and then it is put to move, the density of the submarine will become higher than that of the water, thanks to Lorentz contraction, and hence it sinks. However, in the submarine proper frame, is the water that becomes denser, so the submarine supposedly should float and we get a paradox situation. In this paper we analyze the submarine paradox in both a flat and a curved spacetime. In the case of a flat spacetime, we first show that any relativistic force field in special relativity can be written in the Lorentz form, so that it can always be decomposed into a static (electric-like) and a dynamic (magnetic-like) part. Taking into account the gravitomagnetic effects between the Earth and the water, a relativistic formulation of Archimedes principle can be established, ...
Maximilien Brice
2011-01-01
21 March 2011 - South African Ministry of Science and Technology, Department of Science and Technology (DST) Director General P. Mjwara signing the guest with Head of International Relations F. Pauss and Adviser J. Ellis and ALICE Collaboration Spokesperson P. Giubellino and J. Cleymans; in the CERN control centre with R. Steerenberg; visiting ALICE surface exhibition with P. Giubellino and LHC superconducting magnet test hall with L. Bottura.
Vänttinen, T; Blomqvist, M; Luhtanen, P; Häkkinen, K
2010-06-01
This study of perceptual and motor skills in soccer players was conducted on adolescent males. The goals were to monitor the development of general perceptual motor skills in nonsoccer-playing and soccer-playing groups (n = 245), to examine the relationship between physical maturity and general perceptual motor skills (n = 41), and to compare the differences in general perceptual motor skills between groups with different soccer expertise (n = 142). The measured variables were simple reaction time, peripheral awareness, eye-hand-foot coordination, and testosterone blood level. The results suggested that general perceptual motor skills improved with age, the development of these skills was related to participants' blood testosterone concentration (especially between 12 and 14 years), and general perceptual motor skills improved with soccer expertise. However, the differences between subelite and elite soccer players were not meaningful enough to encourage practitioners to test general perceptual motor skills on a large scale when evaluating the potential of young players.
Generalizations of Hölder’s and Some Related Integral Inequalities on Fractal Space
Directory of Open Access Journals (Sweden)
Guang-Sheng Chen
2013-01-01
Full Text Available Based on the local fractional calculus, we establish some new generalizations of Hölder’s inequality. By using it, some related results on the generalized integral inequality in fractal space are investigated in detail.
Generalized local test for local extrema in single-variable functions
Gkioulekas, Eleftherios
2014-01-01
We give a detailed derivation of a generalization of the second derivative test of single-variable calculus which can classify critical points as local minima or local maxima (or neither), whenever the traditional second derivative test fails, by considering the values of higher-order derivatives evaluated at the critical points. The enhanced test is local, in the sense that it is only necessary to evaluate all relevant derivatives at the critical point itself, and it is reasonably robust. We illustrate an application of the generalized test on a trigonometric function where the second derivative test fails to classify some of the critical points.
Zhang, Ying; Cabilio, Paul
2013-05-10
Focusing on statistical methods in patient-reported outcomes, we propose and develop a generalized Jonckheere test against ordered alternatives for repeated measures in a randomized block design. We derive its asymptotic null distribution properties and describe methods for estimating the null distribution for testing the hypothesis. We present a numerical example to illustrate the test procedure. Copyright © 2012 John Wiley & Sons, Ltd.
Validation of a Test Measuring Young Learners' General L2 English Vocabulary Knowledge
Sylvén, Liss Kerstin; Sundqvist, Pia
2016-01-01
This study aims to present the validation of a test designed to assess young learners' general L2 English vocabulary knowledge, the Young Learner Vocabulary Assessment Test (YLVAT). YLVAT consists of 37 items selected from the K1-2 frequency levels of the Productive and Vocabulary Levels Tests. In the study, Swedish learners (N = 52, age 12) took…
42 CFR 84.1143 - Dust, fume, and mist air-purifying filter tests; performance requirements; general.
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Dust, fume, and mist air-purifying filter tests; performance requirements; general. 84.1143 Section 84.1143 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Man tests for gases and vapors; supplied-air respirators; general performance requirements. 84.159 Section 84.159 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...
Nelson, Jack Jay
The report describes a study designed to follow up successful examinees of the General Educational Development (GED) test administered at McLennan Community College. The study's purpose was to determine the trends, traits, and effects of specific aspects related to their receipt of a high school equivalency certificate. Of the 1,065 successful…
DEFF Research Database (Denmark)
Lundstrøm, Sanne Lykke; Edwards, Kasper; Reventlow, Susanne
2014-01-01
In this paper we investigate the association between relational coordination among the practice team in general practice and number of consultations performed in a general practice per staff, i.e. a proxy of productivity. We measured relational coordination using the Relational Coordination Survey...
Slieker-ten Hove, Marijke; Pool-Goudzwaard, Annelies; Eijkemans, René; Steegers-Theunissen, Régine; BURGER, Curt; Vierhout, M.E.
2009-01-01
markdownabstractINTRODUCTION AND HYPOTHESIS: The objective of this study is to describe pelvic floor muscle function (PFMF) in relation to age and parity in a general female population and to test whether strength/endurance measurements represent all functions of the pelvic floor musculature. METHODS: A cross-sectional study was performed on 95% of the women aged 45-85 years from a small Dutch town. Validated questionnaires were used to obtain general information, and vaginal examination to t...
General anaesthesia-induced anaphylaxis: impact of allergy testing on subsequent anaesthesia.
Trautmann, A; Seidl, C; Stoevesandt, J; Seitz, C S
2016-01-01
Immunoglobulin E-mediated allergy to drugs and substances used during general anaesthesia as well as non-allergic drug hypersensitivity reactions may account for anaesthesia-induced anaphylaxis. As IgE-mediated anaphylaxis is a potentially life-threatening reaction, identification of the culprit allergen is essential to avoid anaphylaxis recurrence during subsequent general anaesthesia. To study whether preventive recommendations derived from allergy testing after intraoperative anaphylaxis were followed in subsequent general anaesthesia. Results of standardized allergy testing after anaesthesia-induced anaphylaxis and outcome of subsequent general anaesthesia were analysed retrospectively. Fifty-three of 107 patients were diagnosed with IgE-mediated allergy to a drug or substance used during general anaesthesia, and 54 patients were test negative. Twenty-eight of 29 allergy patients tolerated subsequent general anaesthesia uneventfully. One patient with cefazolin allergy suffered from anaphylaxis recurrence due to accidental reapplication of cefazolin. Twenty-two of 24 test-negative patients tolerated subsequent general anaesthesia, whereas two patients again developed anaphylaxis despite pre-medication regimens. Our results confirm the practical impact of allergy testing in general anaesthesia-induced anaphylaxis. By identification of the allergen, it is possible to avoid allergic anaphylaxis during subsequent anaesthesia. In most cases, recommended pre-medication seems to prevent the recurrence of non-allergic drug hypersensitivity reactions. © 2015 John Wiley & Sons Ltd.
Changes in pathology test ordering by early career general practitioners: a longitudinal study.
Magin, Parker J; Tapley, Amanda; Morgan, Simon; Henderson, Kim; Holliday, Elizabeth G; Davey, Andrew R; Ball, Jean; Catzikiris, Nigel F; Mulquiney, Katie J; van Driel, Mieke L
2017-07-17
To assess the number of pathology tests ordered by general practice registrars during their first 18-24 months of clinical general practice. Longitudinal analysis of ten rounds of data collection (2010-2014) for the Registrar Clinical Encounters in Training (ReCEnT) study, an ongoing, multicentre, cohort study of general practice registrars in Australia. The principal analysis employed negative binomial regression in a generalised estimating equations framework (to account for repeated measures on registrars).Setting, participants: General practice registrars in training posts with five of 17 general practice regional training providers in five Australian states. The registrar participation rate was 96.4%. Number of pathology tests requested per consultation. The time unit for analysis was the registrar training term (the 6-month full-time equivalent component of clinical training); registrars contributed data for up to four training terms. 876 registrars contributed data for 114 584 consultations. The number of pathology tests requested increased by 11% (95% CI, 8-15%; P pathology test ordering by general practice registrars increased significantly during their first 2 years of clinical practice. This causes concerns about overtesting. As established general practitioners order fewer tests than registrars, test ordering may peak during late vocational training and early career practice. Registrars need support during this difficult period in the development of their clinical practice patterns.
Bjerrum, L; Grinsted, P; Petersen, P H; Søgaard, P
2000-12-01
To investigate whether the validity of susceptibility testing in general practice would improve when preceded by an intervention. Instruction in standardised susceptibility testing procedures given by laboratory instructors. Urine specimens containing monocultures of typical uropathogenic bacteria were sent to 23 general practices before and after the intervention. Practices performed susceptibility testing by the Sensicult and the Iso-Res agar methods and the validity of the results before and after the intervention was compared. Results from susceptibility testing at the bacteriological laboratory, Odense University Hospital, were used as gold standard. The median frequency of correct results increased from 82% to 98% for susceptibility testing based on Sensicult (p = 0.001) and from 90% to 96% based on Iso-Res agar (p = 0.05). The validity of susceptibility testing in general practice improves when preceded by instruction in standardised procedures.
Constraining the angular momentum of the Sun with planetary orbital motions and general relativity
Iorio, Lorenzo
2011-01-01
The angular momentum of a star is an important astrophysical quantity related to its internal structure, formation and evolution. On average, helioseismology yields S = 1.92 10^41 kg m^2 s^-1 for the angular momentum of the Sun. We constrain it in a model-independent, dynamical way by using the gravitomagnetic Lense-Thirring effect predicted by general relativity for the orbit of a test particle moving around a central rotating body. The correction to the standard Einsteinian/Newtonian precession of the longitude of the perihelion $ of Mercury, recently inferred by a team of astronomers from a fit of dynamical models of the forces acting on the planets of the solar system to a long data record, amounts to 0.4 +/- 0.6 mas cty^-1. The modeled forces did not include the Lense-Thirring effect itself, which is expected to be as large as -2.0 mas cty^-1 for the perihelion of Mercury from helioseismological values of S?. By assuming the validity of general relativity, from its theoretical prediction for the gravitom...
Determinants of general practitioner's cancer-related gut feelings—a prospective cohort study
Donker, Gé A; Wiersma, Eva; van der Hoek, Lucas; Heins, Marianne
2016-01-01
Background General practitioners (GPs) use gut feelings to diagnose cancer in an early stage, but little is known about its impact. Method Prospective cohort study of patients in 44 general practices throughout the Netherlands, from January 2010 until December 2013. GPs completed a questionnaire regarding gut feelings, patient and GP characteristics, if they noticed a cancer-related gut feeling during patient consultation. Follow-up questionnaires were sent 3 months later requesting information about the patient's diagnosis. χ2, univariate and multivariate logistic regression and multilevel analyses were performed. Results A gut feeling (N=366) is most often triggered by weight loss (24%, N=85) and rare GP visits (22%, N=76), but all triggers were not predictive of cancer in a multivariate analysis. Most GPs (95%) acted immediately on the gut feeling, either referring to a specialist or by performing additional medical tests. The average positive predictive value of cancer-related gut feeling was 35%, and it increased with 2% for every year a patient becomes older, and with 3% for every year a GP becomes older. Conclusions GP's gut feeling for cancer proves to be a useful tool in diagnosing cancer and its relative high predicting value increases if the GP is older or more experienced and when the patient is older. How can younger GPs be trained to increase the predictive value of their gut feeling? PMID:27625064
ASTROD I - Astrodynamical Space Test of Relativity using Optical Devices
Selig, Hanns; Ni, Wei-Tou; Laemmerzahl, Claus
In 2011 ASTROD I has been selected as one of the final 14 candidates for the Cosmic Vision M3 mission. ASTROD I is a planned interplanetary space mission with multiple goals. The primary aims are: to test general relativity with an improvement in sensitivity of over three orders of magnitude, improving our understanding of gravity and aiding the development of a new quantum gravity theory; to measure key solar system parameters with increased accuracy, advancing solar physics and our knowledge of the solar system; and to measure the time rate of change of the gravitational constant with an order of magnitude improvement and probing dark matter and dark energy gravitationally. It is an international project, and is envisaged as the first in a series of ASTROD missions. ASTROD I will consist of one spacecraft carrying a telescope, four lasers, two event timers and a clock. Two-way, two-wavelength laser pulse ranging will be used between the spacecraft in a solar orbit and deep space laser stations on Earth, to achieve the ASTROD I goals. Finally the mission was not selected for the final 4 candidates for CV M3 in 2011. Nevertheless, ASTROD is a very promising concept for a fundamental physics space mission and shares some key technologies with other popular space missions like LISA and Jason 2 (T2L2). We have also considered possibilities (i) to add an ASTROD I laser ranging package to other fundamental missions for testing the dynamics of relativistic gravity; (ii) to fully combine ASTROD I with another fundamental mission using basic technology of the LISA Pathfiner (this could also be good for a LISA-type mission scheduled to launch 20 years later). In this paper, we present various possibilities of our study.
Holme, Thomas
2014-01-01
Two different versions of "big ideas" rooted content maps have recently been published for general chemistry. As embodied in the content outline from the College Board, one of these maps is designed to guide curriculum development and testing for advanced placement (AP) chemistry. The Anchoring Concepts Content Map for general chemistry…
Testing for Spanning with Futrures Contracts and Nontraded Assets : A General Approach
Nijman, T.E.; de Roon, F.A.; Werker, B.J.M.
1996-01-01
This paper generalizes the notion of mean-variance spanning as de- ned in the seminal paper of Huberman & Kandel (1987) in three di- mensions.It is shown how regression techniques can be used to test for spanning for more general classes of utility functions, in case some as- sets are nontraded, and
M.C.P. Slieker-ten Hove (Marijke); A.L. Pool-Goudzwaard (Annelies); M.J.C. Eijkemans (René); R.P.M. Steegers-Theunissen (Régine); C.W. Burger (Curt); M.E. Vierhout
2009-01-01
markdownabstractINTRODUCTION AND HYPOTHESIS: The objective of this study is to describe pelvic floor muscle function (PFMF) in relation to age and parity in a general female population and to test whether strength/endurance measurements represent all functions of the pelvic floor musculature.
Fast and general tests of genetic interaction for genome-wide association studies.
Frånberg, Mattias; Strawbridge, Rona J; Hamsten, Anders; de Faire, Ulf; Lagergren, Jens; Sennblad, Bengt
2017-06-01
A complex disease has, by definition, multiple genetic causes. In theory, these causes could be identified individually, but their identification will likely benefit from informed use of anticipated interactions between causes. In addition, characterizing and understanding interactions must be considered key to revealing the etiology of any complex disease. Large-scale collaborative efforts are now paving the way for comprehensive studies of interaction. As a consequence, there is a need for methods with a computational efficiency sufficient for modern data sets as well as for improvements of statistical accuracy and power. Another issue is that, currently, the relation between different methods for interaction inference is in many cases not transparent, complicating the comparison and interpretation of results between different interaction studies. In this paper we present computationally efficient tests of interaction for the complete family of generalized linear models (GLMs). The tests can be applied for inference of single or multiple interaction parameters, but we show, by simulation, that jointly testing the full set of interaction parameters yields superior power and control of false positive rate. Based on these tests we also describe how to combine results from multiple independent studies of interaction in a meta-analysis. We investigate the impact of several assumptions commonly made when modeling interactions. We also show that, across the important class of models with a full set of interaction parameters, jointly testing the interaction parameters yields identical results. Further, we apply our method to genetic data for cardiovascular disease. This allowed us to identify a putative interaction involved in Lp(a) plasma levels between two 'tag' variants in the LPA locus (p = 2.42 ⋅ 10-09) as well as replicate the interaction (p = 6.97 ⋅ 10-07). Finally, our meta-analysis method is used in a small (N = 16,181) study of interactions in myocardial
Radic-Sestic, Marina; Radovanovic, Vesna; Milanovic-Dobrota, Biljana; Slavkovic, Sanela; Langovic-Milicvic, Ana
2013-01-01
The general objective of this study was to establish the relation between general and special education teachers within teamwork and to define socio-demographic factors that affect teamwork. The sample encompassed 223 general and special education teacher of both genders, age 25 to 60, who are employed in regular elementary schools in Serbia. The…
Directory of Open Access Journals (Sweden)
Hossein Dargahi
2016-12-01
Full Text Available Considering the fact that students studying various fields of Study will have the responsibility to create, maintain and improve society’s level of health, they should be cared for with precision so they can perform and play their role as an educated and expert work force. this is due to the fact that getting accepted in university is a very sensitive period in lives of efficient workforce and active youth in each country, therefore, present study determines the relation between general health and educational progress among paramedical faculty’s Students of Tehran Medical University. Method: present research has a descriptive-analytic nature and was executed in a time period during winter of 2016. the target society included all students of paramedical faculty and required data was gathered by an adults’ health function literacy questionnaire and general health was also gathered by means of general health questionnaire. in order to present descriptive results of percentage and median and to study and analyses quantitative data, parametric statistical tests was used for normal data and in case there were not normal, unparametric tests were applied. Findings: Results of present study showed that there is a positive significant relation between general health and educational progress (r=01 / 0 p <،28 / 0. Still, no significant relation was observed between general health and health literacy (r= 0.038, p=0.569. Conclusion: In studying general health aspects with health literacy and educational health motivation, all aspects of general health (physical aspect, anxiety aspect, social function aspect, depression aspect showed a direct and significant relation with educational progress but presented no significant relation with health literacy. Still, we could observe a positive effect on educational progress and health literacy by trying to improve any of general health factors. In other words, we could use organizational capitals to improve
Indian Academy of Sciences (India)
Page S20: NMR compound 4i. Page S22: NMR compound 4j. General: Chemicals were purchased from Fluka, Merck and Aldrich Chemical Companies. All the products were characterized by comparison of their IR, 1H NMR and 13C NMR spectroscopic data and their melting points with reported values. General procedure ...
FORTRAN implementation of Friedman's test for several related samples
Davidson, S. A.
1982-01-01
The FRIEDMAN program is a FORTRAN-coded implementation of Friedman's nonparametric test for several related samples with one observation per treatment/-block combination, or as it is sometimes called, the two-way analysis of variance by ranks. The FRIEDMAN program is described and a test data set and its results are presented to aid potential users of this program.
General anesthesia in orthognathic surgeries: does it affect horizontal jaw relations?
Yaghmaei, Masoud; Ejlali, Masoud; Nikzad, Sekieneh; Sayyedi, Ashraf; Shafaeifard, Shahrouz; Pourdanesh, Fereydoun
2013-10-01
The aim of this study was to evaluate the influence of general anesthesia on centric jaw relation (CR) records of orthognathic surgical patients in different postural positions. Fifty patients undergoing orthognathic surgery at Taleghani Hospital (Tehran, Iran) in 2008 were prospectively studied. CR records were obtained in conscious patients in 2 different positions (upright and supine) 1 day before surgery and in the supine position under general anesthesia. The impressions were made and the corresponding casts were mounted on a semiadjustable articulator. Differences were measured to the nearest 0.10 mm using a caliper. Paired t test and a general linear regression model were used for statistical analysis. Fifty patients (27 women and 23 men; mean age, 22.5 ± 3.5 yr) were enrolled. Angle Class I (group I), Class II (group II), and Class III (group III) malocclusions were detected in 16% (n = 8), 54% (n = 27), and 30% (n = 15) of patients, respectively. Although mean changes were smaller than 2 mm, statistically significant differences were found by paired t test in all Angle classification groups. No significant differences were found between the supine and conscious and the supine and unconscious patient positions in groups I and III (P > .05). However, in group II, this difference was statistically significant (P = .001). Regarding the impact of anesthesia on CR records of patients with different Angle classes, this study showed a significant effect, particularly in group II. Assessment of the outcome of interest (difference between the supine and conscious and the upright and conscious positions) versus position after adjustment for Angle class using a general linear regression model showed that the difference was significant only for Angle class (β = +0.29; t = 3.05; P = .003). General anesthesia may not adversely affect the mandibular condylar position in orthognathic patients in a supine position compared with a supine and conscious position. However
Transfer of function and prior derived-relations testing.
Doughty, Adam H; Best, Lauren
2017-10-01
This experiment assessed transfer of function through equivalence relations with and without prior derived-stimulus-relations (DSR) testing. In a DSR-Testing Group, eight college students learned A-B and A-C discriminations in baseline. They then derived the B-C and C-B equivalence relations before being exposed to a transfer-of-function manipulation and test. Eight participants in a No-DSR Testing Group were exposed to the transfer-of-function manipulation and test immediately after learning the baseline discriminations (i.e., B-C and C-B testing were omitted). In the transfer-of-function manipulation, participants learned to respond differently in the presence of B1 and B2 to avoid money loss. In the transfer-of-function test, responding in the presence of C1 and C2 was measured in the absence of differential consequences. Transfer of function occurred reliably only in the DSR-Testing Group (i.e., participants responding to C1 and C2 in the manner they learned to respond to B1 and B2, respectively). These findings support the notion that prior DSR testing can be critical to observing transfer of function. Copyright © 2017 Elsevier B.V. All rights reserved.
Yun, Ilhong; Kim, Seung-Gon; Kwon, Sangro
2016-08-01
Theoretical propositions and empirical tests of Gottfredson and Hirschi's general theory continue to permeate the criminological literature. Nevertheless, the vast majority of studies have been conducted in North America and some European countries. Only a handful of empirical works have been conducted in East Asia. To further test the generality assertion of Gottfredson and Hirschi, the current study examines low self-control's efficacy in predicting the involvement of South Korean adolescents in typical delinquency, drinking, smoking, Internet addiction, and smartphone addiction. The presented findings largely support the generality hypothesis, although the theorists' assertion seems to be somewhat overstated. © The Author(s) 2015.
26 CFR 54.4975-1 - General rules relating to excise tax on prohibited transactions.
2010-04-01
... 26 Internal Revenue 17 2010-04-01 2010-04-01 false General rules relating to excise tax on prohibited transactions. 54.4975-1 Section 54.4975-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES (CONTINUED) PENSION EXCISE TAXES § 54.4975-1 General rules relating to excise tax on prohibite...
General relativity the most beautiful of theories : applications and trends after 100 years
2015-01-01
Generalising Newton's law of gravitation, general relativity is one of the pillars of modern physics. On the occasion of general relativity's centennial, leading scientists in the different branches of gravitational research review the history and recent advances in the main fields of applications of the theory, which was referred to by Lev Landau as “the most beautiful of the existing physical theories”.
ACADEMIC TRAINING LECTURE SERIES: Introduction to General Relativity and Black Holes
2003-01-01
10, 11, 12, 13, 14 February ACADEMIC TRAINING LECTURE SERIES from 11.00 to 12.00 hrs - Auditorium, bldg. 500 Introduction to General Relativity and Black Holes by T.DAMOUR, IHES, Bures-sur-Yvette, F - Physical motivation behind Einstein's theory. - Mathematical formalism of General Relativity. - Experimental confirmations of Einstein's theory. - Introduction to Black Holes physics.
Relative Deprivation and Adolescent Outcomes in Iceland: A Multilevel Test
Bernburg, Jon Gunnar; Thorlindsson, Thorolfur; Sigfusdottir, Inga Dora
2009-01-01
The theory of relative deprivation emphasizes that social comparisons contextualize how people experience impoverishment. An important application of this theory argues that relative deprivation that stems from unfavorable social comparisons can result in anger, normlessness and an increased likelihood of deviant behavior. We test this theory in a…
24 CFR 598.110 - Tests of pervasive poverty, unemployment and general distress.
2010-04-01
... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Tests of pervasive poverty... TWO AND THREE DESIGNATIONS Eligibility Requirements § 598.110 Tests of pervasive poverty, unemployment and general distress. (a) Pervasive poverty. Pervasive poverty is demonstrated by evidence that: (1...
24 CFR 597.102 - Tests of pervasive poverty, unemployment and general distress.
2010-04-01
... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Tests of pervasive poverty... ENTERPRISE COMMUNITIES: ROUND ONE DESIGNATIONS Area Requirements § 597.102 Tests of pervasive poverty, unemployment and general distress. (a) Pervasive poverty. Pervasive poverty shall be demonstrated by the...
Evaluation and Management of Patch Test-Negative Patients With Generalized Dermatitis.
Spiker, Alison; Mowad, Christen M
Patients with generalized dermatitis are common in dermatology practices. Allergic contact dermatitis is often suspected, and patients frequently undergo patch testing. When the patch testing result is negative, further evaluation and management of these patients are challenging. The purpose of this study was to survey members of the American Contact Dermatitis Society regarding the evaluation and management of patch test-negative patients with generalized dermatitis. Generalized dermatitis was the most common term identified for patch test-negative patients with diffuse dermatitis. After having negative expanded patch testing results, most physicians proceeded with additional testing including skin biopsy, complete blood cell count with differential, and liver and renal function tests. The most commonly used systemic treatment is prednisone, followed by methotrexate. Narrow-band ultraviolet B (UVB) is the most commonly used light source. Antihistamines are frequently prescribed. Food allergy is not felt to be causative. This cohort of patients experiences significant impairment in quality of life, stress on personal relationships, and time off work. The management of patch test-negative patients with generalized dermatitis is challenging. This study provides insight into management of these complex patients. It also demonstrates practice gaps in the management of these patients, indicating a need for further studies to direct the evaluation and management of this patient population.
A multivariate family-based association test using generalized estimating equations : FBAT-GEE
Lange, C; Silverman, SK; Xu, [No Value; Weiss, ST; Laird, NM
In this paper we propose a multivariate extension of family-based association tests based on generalized estimating equations. The test can be applied to multiple phenotypes and to phenotypic data obtained in longitudinal studies without making any distributional assumptions for the phenotypic
BOOK REVIEW: Einstein's Jury: The Race to Test Relativity
Ehlers, Jürgen
2007-10-01
'I know very well that my theory rests on a shaky foundation. What attracts me to it is that it leads to consequences that seem to be accessible to experiment, and it provides a starting point for the theoretical understanding of gravitation', wrote Einstein in 1911. Einstein's Jury by Jeffrey Crelinsten—well documented, well written, and fascinating to read—describes how, from 1909 on, Einstein's two theories of relativity became known to astronomers, and how the predictions made between 1907 and 1915 were received as challenges to observers. The author gives a non-technical account of the efforts made until 1930 to test these predictions; he focuses on two of the three classical tests, namely gravitational redshift and bending of light; the 'jury' consists mainly of American observers—Adams, Campbell, Curtis, Hale, Perrin, St John, Trumpler and others—working with newly built large telescopes, and the Britons Eddington and Evershed. The major steps which, after a long struggle, convinced the majority of astronomers that Einstein was right, are narrated chronologically in rather great detail, especially the work at Lick Observatory, before and after the famous British observation of 1919, on solar eclipses, and the work at Mount Wilson and the Indian Kodaikanal Observatories to extract the gravitational redshift from the complicated spectrum of the sun. The account of the eclipse work which was carried out between 1918 and 1923 by Lick astronomers corrects the impression suggested by many historical accounts that the British expedition alone settled the light-bending question. Apart from these main topics, the anomalous perihelion advance of Mercury and the ether problem are covered. By concentrating on astronomy rather than on physics this book complements the rich but repetitive literature on Einstein and relativity which appeared in connection with the commemoration of Einstein's annus mirabilis, 2005. The well told stories include curiosities such as
New tests of the distal speech rate effect: Examining cross-linguistic generalization
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Laura eDilley
2013-12-01
Full Text Available Recent findings [Dilley and Pitt, 2010. Psych. Science. 21, 1664-1670] have shown that manipulating context speech rate in English can cause entire syllables to disappear or appear perceptually. The current studies tested two rate-based explanations of this phenomenon while attempting to replicate and extend these findings to another language, Russian. In Experiment 1, native Russian speakers listened to Russian sentences which had been subjected to rate manipulations and performed a lexical report task. Experiment 2 investigated speech rate effects in cross-language speech perception; non-native speakers of Russian of both high and low proficiency were tested on the same Russian sentences as in Experiment 1. They decided between two lexical interpretations of a critical portion of the sentence, where one choice contained more phonological material than the other (e.g., /stərʌ'na/ side vs. /strʌ'na/ country. In both experiments, with native and non-native speakers of Russian, context speech rate and the relative duration of the critical sentence portion were found to influence the amount of phonological material perceived. The results support the generalized rate normalization hypothesis, according to which the content perceived in a spectrally ambiguous stretch of speech depends on the duration of that content relative to the surrounding speech, while showing that the findings of Dilley and Pitt (2010 extend to a variety of morphosyntactic contexts and a new language, Russian. Findings indicate that relative timing cues across an utterance can be critical to accurate lexical perception by both native and non-native speakers.
Trienekens, Suzan C M; van den Broek, Ingrid V F; Donker, Gé A; van Bergen, Jan E A M; van der Sande, Marianne A B
2013-12-30
In the Netherlands, sexually transmitted infection (STI) care is provided by general practitioners (GPs) as well as by specialised STI centres. Consultations at the STI centres are monitored extensively, but data from the general practice are limited. This study aimed to examine STI consultations in the general practice. Prospective observational patient survey. General practices within the nationally representative Dutch Sentinel GP network (n=125 000 patient population), 2008-2011. GPs were asked to fill out a questionnaire at each STI consultation addressing demographics, sexual behaviour and laboratory test results. Patient population, testing practices and test positivity are reported. Patients attending a consultation concerning an STI/HIV-related issue. Overall, 1 in 250 patients/year consulted their GP for STI/HIV-related problems. Consultations were concentrated among young heterosexuals of Dutch origin. Laboratory testing was requested for 83.3% of consultations. Overall consult positivity was 33.4%, highest for chlamydia (14.7%), condylomata (8.7%) and herpes (6.4%). 32 of 706 positive patients (4.5%) were diagnosed with multiple infections. Main high-risk groups were patients who were 25 years old (syphilis), men who have sex with men (MSM; for gonorrhoea/syphilis/HIV) or having symptoms (for any STI). Adherence to guideline-recommendations to test for multiple STI among high-risk groups varied from 15% to 75%. This study found that characteristics of patients who consulted a GP for STIs were comparable to those of patients attending STI centres regarding age and ethnicity; however, consultations of high-risk groups like MSM and (clients of) commercial sex workers were reported less by the general practice. Where the STI centres routinely test all patients for chlamydia/syphilis/HIV/gonorrhoea, GPs tested more selectively, even more restricted than advised by GP guidelines. Test positivity was, therefore, higher in general practice, although it is
Templer, Victoria L; Hampton, Robert R
2012-05-01
The possibility that memory awareness occurs in nonhuman animals has been evaluated by providing opportunity to decline memory tests. Current evidence suggests that rhesus monkeys (Macaca mulatta) selectively decline tests when memory is weak (Hampton in Proc Natl Acad Sci USA 98:5359-5362, 2001; Smith et al. in Behav Brain Sci 26:317-374, 2003). However, much of the existing research in nonhuman metacognition is subject to the criticism that, after considerable training on one test type, subjects learn to decline difficult trials based on associative learning of external test-specific contingencies rather than by evaluating the private status of memory or other cognitive states. We evaluated whether such test-specific associations could account for performance by presenting monkeys with a series of generalization tests across which no single association with external stimuli was likely to adaptively control use of the decline response. Six monkeys performed a four alternative delayed matching to location task and were significantly more accurate on trials with a decline option available than on trials without it, indicating that subjects selectively declined tests when memory was weak. Monkeys transferred appropriate use of the decline response under three conditions that assessed generalization: two tests that weakened memory and one test that enhanced memory in a novel way. Bidirectional generalization indicates that use of the decline response by monkeys is not controlled by specific external stimuli but is rather a flexible behavior based on a private assessment of memory.
Dental treatment under general anaesthetic and children's oral health-related quality of life.
Martins-Junior, Paulo A
2017-10-27
Data sourcesMedline, Scopus and the Web of Science.Study selectionStudies conducted in children under 16 undergoing general anaesthesia having change in oral health-related quality of life were considered. Selection was undertaken by two reviewers independently.Data extraction and synthesisData abstraction was undertaken independently by three groups of two reviewers - discrepancies were resolved by discussion. Study quality was assessed using the Quality Assessment Tool for Studies of Diverse Design (QATSDD).ResultsTwenty studies were included; there were 18 prospective studies, one randomised trial and one secondary analysis study. Most studies used a pre-test-post-test design and all but one used proxy measures of oral health-related quality of life (OHRQoL). All of the studies reported improved OHRQoL overall. However, results suggested that some aspects of OHRQoL may worsen.ConclusionsHeterogeneity of included papers limited the conclusions which could be drawn. Treatment under GA appears to result in overall improvements in proxy-reported OHRQoL; however, there is a need for further high-quality studies employing validated, child-reported measures of OHRQoL.
Approach/avoidance motives, test emotions, and emotional regulation related to testing.
Schutz, Paul A; Benson, Jeri; Decuir-Gunby, Jessica T
2008-07-01
This research stems from our program of work that focuses on understanding how students regulated their emotions related to testing. The primary goal for this study was to incorporate the approach/ avoidance motives into a model of emotional regulation related to testing. In addition, a secondary goal was to report on efforts at construct validation of the scores obtained during the refinement of the Emotional Regulation Related to Testing (ERT) Scale. Our results suggest that underlying beliefs, such as approach/avoid motives and the cognitive-appraisal process, of the ERT had both direct and indirect effects to both pleasant and unpleasant emotions related to testing. In addition, the ERT accounted for 56% of the variance in Pleasant and 87% of Unpleasant Test Emotions.
How to test for a relative afferent pupillary defect (RAPD)
David C Broadway
2016-01-01
The 'swinging light test' is used to detect a relative afferent pupil defect (RAPD): a means of detecting differences between the two eyes in how they respond to a light shone in one eye at a time. The test can be very useful for detecting unilateral or asymmetrical disease of the retina or optic nerve (but only optic nerve disease that occurs in front of the optic chiasm).
How to test for a relative afferent pupillary defect (RAPD
Directory of Open Access Journals (Sweden)
David C Broadway
2012-01-01
Full Text Available The 'swinging light test' is used to detect a relative afferent pupil defect (RAPD: a means of detecting differences between the two eyes in how they respond to a light shone in one eye at a time. The test can be very useful for detecting unilateral or asymmetrical disease of the retina or optic nerve (but only optic nerve disease that occurs in front of the optic chiasm.
General Aviation Flight Test of Advanced Operations Enabled by Synthetic Vision
Glaab, Louis J.; Hughhes, Monica F.; Parrish, Russell V.; Takallu, Mohammad A.
2014-01-01
A flight test was performed to compare the use of three advanced primary flight and navigation display concepts to a baseline, round-dial concept to assess the potential for advanced operations. The displays were evaluated during visual and instrument approach procedures including an advanced instrument approach resembling a visual airport traffic pattern. Nineteen pilots from three pilot groups, reflecting the diverse piloting skills of the General Aviation pilot population, served as evaluation subjects. The experiment had two thrusts: 1) an examination of the capabilities of low-time (i.e., <400 hours), non-instrument-rated pilots to perform nominal instrument approaches, and 2) an exploration of potential advanced Visual Meteorological Conditions (VMC)-like approaches in Instrument Meteorological Conditions (IMC). Within this context, advanced display concepts are considered to include integrated navigation and primary flight displays with either aircraft attitude flight directors or Highway In The Sky (HITS) guidance with and without a synthetic depiction of the external visuals (i.e., synthetic vision). Relative to the first thrust, the results indicate that using an advanced display concept, as tested herein, low-time, non-instrument-rated pilots can exhibit flight-technical performance, subjective workload and situation awareness ratings as good as or better than high-time Instrument Flight Rules (IFR)-rated pilots using Baseline Round Dials for a nominal IMC approach. For the second thrust, the results indicate advanced VMC-like approaches are feasible in IMC, for all pilot groups tested for only the Synthetic Vision System (SVS) advanced display concept.
Testing for minimal consciousness in complex partial and generalized tonic-clonic seizures.
McPherson, Alison; Rojas, Leticia; Bauerschmidt, Andrew; Ezeani, Celestine C; Yang, Li; Motelow, Joshua E; Farooque, Pue; Detyniecki, Kamil; Giacino, Joseph T; Blumenfeld, Hal
2012-10-01
Impaired consciousness in epilepsy has a major negative impact on quality of life. Prior work suggests that complex partial seizures (CPS) and generalized tonic-clonic seizures (GTCS), which both cause loss of consciousness, affect similar frontoparietal networks. Milder involvement in CPS than in GTCS may spare some simple behavioral responses, resembling the minimally conscious state. However, this difference in responses has not been rigorously tested previously. During video-electroencephalography (EEG) monitoring, we administered a standardized prospective testing battery including responses to questions and commands, as well as tests for reaching/grasping a ball and visual tracking in 27 CPS (in 14 patients) and 7 GTCS (in six patients). Behavioral results were analyzed in the ictal and postictal periods based on video review. During both CPS and GTCS, patients were unable to respond to questions or commands. However, during CPS, patients often retained minimally conscious ball grasping and visual tracking responses. Patients were able to successfully grasp a ball in 60% or to visually track in 58% of CPS, and could carry out both activities in 52% of CPS. In contrast, during GTCS, preserved ball grasp (10%), visual tracking (11%), or both (7%), were all significantly less than in CPS. Postictal ball grasping and visual tracking were also somewhat better following CPS than GTCS. These findings suggest that impaired consciousness in CPS is more similar to minimally conscious state than to coma. Further work may elucidate the specific brain networks underlying relatively spared functions in CPS, ultimately leading to improved treatments aimed at preventing impaired consciousness. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.
Generalized radial flow interpretation of well tests for the SITE-94 project
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Geier, J.E.; Benabderrahman, A.; Haessler, L. [Golder Associates AB, Uppsala (Sweden); Doe, T.W. [Golder Associates, Inc., Redmond, WA (United States)
1996-12-01
Transient flow data from constant-head injection tests at the Aespoe site, in the boreholes KAS 02-08, were analyzed using a generalized radial flow (GRF) model for interpretation. The analyses yielded estimates of flow dimensionality, conductivity, and transmissivity which may be used in the development and validation of conceptual models, and to assess the quality of the existing Aespoe conductivity database, for use in the SITE-94 project. Half of the tests in 3 m packer section, and one third of the tests in 30 m sections were not interpretable in terms of the GRF model, due to very low flows, indicating tight sections. A discussion is given of the contrasting pattern of dimensionality and transmissivity among the main structural units, and of the implications of these patterns for the problem of choosing appropriate conceptual models. Smaaland granite and the fracture zone EW-X, in particular, contain highly transmissive, low-dimension conduits, which suggest the likelihood of channel-like conduits that could provide fast transport paths, with relatively low buffering capacity, for radionuclides in the far field. Other rock units and fracture zones show behaviour that may be reproducible by less strongly heterogeneous conceptual models, such as an effective porous medium with embedded, transmissive, planar features. The conductance arising from the low-dimension conduits is probably underestimated in the existing Aespoe conductivity dataset, because of the use of interpretation methods based on cylindrical flow. The Moye`s formula estimates in the database are also affected by problems of low resolution for the flow measurements. 42 refs.
Determinants of general practitioner's cancer-related gut feelings-a prospective cohort study.
Donker, Gé A; Wiersma, Eva; van der Hoek, Lucas; Heins, Marianne
2016-09-13
General practitioners (GPs) use gut feelings to diagnose cancer in an early stage, but little is known about its impact. Prospective cohort study of patients in 44 general practices throughout the Netherlands, from January 2010 until December 2013. GPs completed a questionnaire regarding gut feelings, patient and GP characteristics, if they noticed a cancer-related gut feeling during patient consultation. Follow-up questionnaires were sent 3 months later requesting information about the patient's diagnosis. χ(2), univariate and multivariate logistic regression and multilevel analyses were performed. A gut feeling (N=366) is most often triggered by weight loss (24%, N=85) and rare GP visits (22%, N=76), but all triggers were not predictive of cancer in a multivariate analysis. Most GPs (95%) acted immediately on the gut feeling, either referring to a specialist or by performing additional medical tests. The average positive predictive value of cancer-related gut feeling was 35%, and it increased with 2% for every year a patient becomes older, and with 3% for every year a GP becomes older. GP's gut feeling for cancer proves to be a useful tool in diagnosing cancer and its relative high predicting value increases if the GP is older or more experienced and when the patient is older. How can younger GPs be trained to increase the predictive value of their gut feeling? Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Generic rotating regular black holes in general relativity coupled to nonlinear electrodynamics
Toshmatov, Bobir; Stuchlík, Zdeněk; Ahmedov, Bobomurat
2017-04-01
We construct regular rotating black hole and no-horizon spacetimes based on the recently introduced spherically symmetric generic regular black hole spacetimes related to electric or magnetic charge under nonlinear electrodynamics coupled to general relativity that for special values of the spacetime parameters reduce to the Bardeen and Hayward spacetimes. We show that the weak and strong energy conditions are violated inside the Cauchy horizons of these generic rotating black holes. We give the boundary between the rotating black hole and no-horizon spacetimes and determine the black hole horizons and the boundary of the ergosphere. We introduce the separated Carter equations for the geodesic motion in these rotating spacetimes. For the most interesting new class of the regular spacetimes, corresponding for magnetic charges to the Maxwell field in the weak field limit of the nonlinear electrodynamics, we determine the structure of the circular geodesics and discuss their properties. We study the epicyclic motion of a neutral particle moving along the stable circular orbits around the "Maxwellian" rotating regular black holes. We show that epicyclic frequencies measured by the distant observers and related to the oscillatory motion of the neutral test particle along the stable circular orbits around the rotating singular and regular Maxwellian black holes are always smaller than ones in the Kerr spacetime.
Pototzky, Anthony S; Murphy, Patrick C.
2014-01-01
Improving aerodynamic models for adverse loss-of-control conditions in flight is an area being researched under the NASA Aviation Safety Program. Aerodynamic models appropriate for loss of control conditions require a more general mathematical representation to predict nonlinear unsteady behaviors. As more general aerodynamic models are studied that include nonlinear higher order effects, the possibility of measurements that confound aerodynamic and structural responses are probable. In this study an initial step is taken to look at including structural flexibility in analysis of rigid-body forced-oscillation testing that accounts for dynamic rig, sting and balance flexibility. Because of the significant testing required and associated costs in a general study, it makes sense to capitalize on low cost analytical methods where possible, especially where structural flexibility can be accounted for by a low cost method. This paper provides an initial look at using linear lifting surface theory applied to rigid-body aircraft roll forced-oscillation tests.
Lukowski, Angela F; Milojevich, Helen M
2013-06-01
Previous research suggests that sleep is related to cognitive functioning in infants and adults. In the present study, we examined whether individual differences in infant sleep habits over the seven days prior to elicited imitation testing were associated with variability in (a) the encoding of 2-step event sequences and (b) memory for the presented information and generalization across cues after a 2-h delay in 10-month-olds. Significant correlations indicated that both daytime napping and nighttime sleep were related to encoding and generalization across cues after the 2-h delay; significant findings were not found in relation to baseline or delayed recall performance. We suggest that individual differences in infant sleep habits may be one mechanism underlying the observed variability in recall memory and generalization as these abilities are coming online late in the first year of life. Published by Elsevier Inc.
GRAMMATICAL MISTAKES IN RELATION TO ENGLISH COMPETENCY TEST
Directory of Open Access Journals (Sweden)
I Gusti Ayu Gde Sosiowati
2016-11-01
Full Text Available The research aims at finding out the freshmen’s ability on English grammar. This is very important activity so that the English department knows their level of ability so that the teaching materials can be determined. The test is about structure, taken from TOEFL. The theory used is the theory English Language Teaching, especially Testing by Harmer (2001, in which the test is used as diagnostic test. The result of the test will provide the information about three crucial points on grammar that must be developed. This will help the related teacher to decide what items should be taught so that by the end of the semester, at least most of the students can reach the level of Intermediate, that is the level in which the students are capable of doing conversations on routines, u nderstanding lectures, understanding English TV programs (http://www.embassyenglish.com/student-life/yourlevel-of-english cited on 19 January 2015.
GINGER (Gyroscopes IN General Relativity), a ring lasers array to measure the Lense-Thirring effect
Di Virgilio, Angela D. V.
The purpose of the GINGER is to perform the first test of general relativity (not considering the gravitational redshift measurements) in a terrestrial laboratory, using light as a probe. The experiment will complement the ones in space, performed or under way, with an entirely different technique and at a far lower cost. The methodology is based on ring-lasers, which are extremely accurate rotation sensors and can not only sense purely kinematical rotations (Sagnac effect accounting for the Earth rotation, polar motion of the terrestrial axis, local rotational movements of the laboratory due to the Earth crust dynamics...), but also general relativistic contributions such as the de Sitter effect (coupling between the gravito-electric field of the earth and the kinematical rotation) and the Lense-Thirring effect (inertial frame dragging due to the angular momentum of the earth). In order to reveal the latter effects, ring-laser response must be improved to be able to measure the effective rotation vector (kinematic plus GR terms) with an accuracy of 1 part in 109 or better. This is a challenging technological aspect, which however has been accurately taken into account by designing a system of ring lasers that will be implemented in this project. A ring laser have been installed inside the underground laboratory of GranSasso, with the purpose to see if an underground location is the right choice for GINGER. The apparatus and the preliminary results will be discussed.
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Abade, Gustavo C; Cichocki, Bogdan [Institute of Theoretical Physics, University of Warsaw, Hoza 69, 00-681 Warsaw (Poland); Ekiel-Jezewska, Maria L; Wajnryb, Eligiusz [Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02-106 Warsaw (Poland); Naegele, Gerhard, E-mail: mekiel@ippt.gov.p [Institut fuer Festkoerperforschung, Forschungszentrum Juelich, D-52425 Juelich (Germany)
2010-08-18
We study the high-frequency limiting shear viscosity, {eta}{sub {infinity}}, of colloidal suspensions of uncharged porous particles. An individual particle is modeled as a uniformly porous sphere with the internal solvent flow described by the Debye-Bueche-Brinkman equation. A precise hydrodynamic multipole method with a full account of many-particle hydrodynamic interactions encoded in the HYDROMULTIPOLE program extended to porous particles, is used to calculate {eta}{sub {infinity}}as a function of porosity and concentration. The second-order virial expansion for {eta}{sub {infinity}}is derived, and its range of applicability assessed. The simulation results are used to test the validity of generalized Stokes-Einstein relations between {eta}{sub {infinity}}and various short-time diffusion coefficients, and to quantify the accuracy of a simplifying cell model calculation of {eta}{sub {infinity}.} An easy-to-use generalized Saito formula for {eta}{sub {infinity}}is presented which provides a good description of its porosity and concentration dependence. (fast track communication)
Denison, Julie A.; McCauley, Ann P.; Dunnett-Dagg, Wendy A.; Lungu, Nalakwanji; Sweat, Michael D.
2009-01-01
This study examined how individual, relational and environmental factors related to adolescent demand for HIV voluntary counseling and testing (VCT). A cross-sectional survey among randomly selected 16-19-year-olds in Ndola, Zambia, covered individual (e.g., HIV knowledge), environmental (e.g., distance), and relational factors (e.g., discussed…
Directory of Open Access Journals (Sweden)
Bindels Patrick JE
2006-03-01
Full Text Available Abstract Background General practitioners (GPs frequently order blood tests when they see patients presenting with unexplained complaints. Due to the low prevalence of serious pathology in general practice, the risk of false-positive test results is relatively high. This may result in unnecessary further testing, leading to unfavourable effects such as patient anxiety, high costs, somatisation and morbidity. A policy of watchful waiting is expected to lower both the number of patients to be tested and the risk of false-positive test results, without missing serious pathology. However, many general practitioners experience barriers when trying to postpone blood testing by watchful waiting. The objectives of this study are (1 to determine the accuracy of blood tests in patients presenting with unexplained complaints in terms of detecting pathology, (2 to determine the accuracy of a watchful waiting strategy and (3 to determine the effects of a quality improvement strategy to promote the postponement of blood test ordering by GPs for patients with unexplained complaints. Design General practices are randomised over three groups. Group 1 is instructed to order blood tests immediately, group 2 to apply a watchful waiting policy and group 3 also to postpone testing, but supported by our quality improvement strategy. The trial consists of two sub-studies: a diagnostic study at patient level (group 1 versus groups 2 and 3 and a quality improvement study at GP level (group 2 versus group 3. The diagnostic strategy to be used involves of both customary and innovative tests. The quality improvement strategy consists of two small-group meetings and a practice outreach visit. Patient follow-up ends at 12 months after the initial consultation. Primary outcome measures are the accuracy and added value of blood tests for detecting pathology, the effect of a 4-week postponement of test ordering on the blood test characteristics and the quantity of tests ordered
General movements in the perinatal period and its relation to echogenicity changes in the brain
Rosier-van Dunne, F.M.F.; Wezel-Meijler, G.; Bakker, M.P.; de Groot, L.; Odendaal, H.J.; de Vries, J.I.P.
2010-01-01
Background: In preterm born infants abnormal general movements (GMs) generally normalize before three months post term, but may persist when perinatal brain injury is present. Aims: To assess the continuity of GM quality from fetal to early neonatal period and its relation to brain echogenicity
Racism-Related Stress, General Life Stress, and Psychological Functioning among Black American Women
Pieterse, Alex L.; Carter, Robert T.; Ray, Kilynda V.
2013-01-01
The relationship between general life stress, perceived racism, and psychological functioning was explored in a sample of 118 Black American women. Findings indicate that racism-related stress was not a significant predictor of psychological functioning when controlling for general life stress. Perceived racism was positively associated with…
Muschalla, Beate; Glatz, Johannes; Linden, Michael
2014-01-01
Absence of an adequate reason for anxiety is a criterion for pathological anxiety. However, the presence of danger or fear-provoking stimuli may even be a risk factor for anxiety and does not exclude that there is additionally pathological anxiety too. The question is, to what degree can heart-related anxiety be explained by the severity of illness or trait anxiety? Two hundred and nine patients (37.8% women) from a cardiology inpatient unit completed the Heart-Anxiety-Questionnaire, Progression-Anxiety-Questionnaire, Job-Anxiety-Scale and the State-Trait-Anxiety-Inventory. The severity of cardiac illness was rated by the treating cardiologists using the Multidimensional Severity of Morbidity Rating. Time absent from work due to sickness was assessed as an indicator for illness-related impairment. Heart anxiety was significantly related to progression anxiety and, to a lesser extent, trait anxiety and indicators of subjective symptoms of somatic illness. No association was found with medical ratings for prognosis, multimorbidity, or reduction in life expectancy. Heart-related anxiety is a symptom of an anxiety disorder. Although partially dependent on subjective suffering, it cannot be explained by the severity of medical illness. Treatment of health-related anxieties should focus on how to cope with subjective symptoms of illness.
Does the Fizeau Experiment Really Test Special Relativity?
Clement, Gerard
1980-01-01
The motivation and interpretation of the Fizeau experiment are reviewed, and its status as a test of special relativity is discussed. It is shown, with the aid of a simplified, purely mechanical model of the propagation of light in matter, that the experiment actually cannot discriminate between Galilean and relativistic kinematics. (Author/SK)
Propagators of Generalized Schrödinger Equations Related by First-order Supersymmetry
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A. Schulze-Halberg
2011-01-01
Full Text Available We construct an explicit relation between propagators of generalized Schrödinger equations that are linked by a first-order supersymmetric transformation. Our findings extend and complement recent results on the conventional case [1].
Fisher Sand & Gravel New Mexico, Inc. General Air Quality Permit: Related Documents
Documents related to the Fisher Sand & Gravel – New Mexico, Inc., Grey Mesa Gravel Pit General Air Quality Permit for New or Modified Minor Source Stone Quarrying, Crushing, and Screening Facilities in Indian Country.
Kramer, A.W.M.; Jansen, J.J.; Zuithoff, P.; Dusman, H.; Tan, L.; Grol, R.P.T.M.; Vleuten, C.P.M. van der
2002-01-01
PURPOSE: To examine the validity of a written knowledge test of skills for performance on an OSCE in postgraduate training for general practice. METHODS: A randomly-selected sample of 47 trainees in general practice took a knowledge test of skills, a general knowledge test and an OSCE. The OSCE
Janssen, Michel
2012-08-01
In publications in 1914 and 1918, Einstein claimed that his new theory of gravity in some sense relativizes the rotation of a body with respect to the distant stars (a stripped-down version of Newton's rotating bucket experiment) and the acceleration of the traveler with respect to the stay-at-home in the twin paradox. What he showed was that phenomena seen as inertial effects in a space-time coordinate system in which the non-accelerating body is at rest can be seen as a combination of inertial and gravitational effects in a (suitably chosen) space-time coordinate system in which the accelerating body is at rest. Two different relativity principles play a role in these accounts: (a) the relativity of non-uniform motion, in the weak sense that the laws of physics are the same in the two space-time coordinate systems involved; (b) what Einstein in 1920 called the relativity of the gravitational field, the notion that there is a unified inertio-gravitational field that splits differently into inertial and gravitational components in different coordinate systems. I provide a detailed reconstruction of Einstein's rather sketchy accounts of the twins and the bucket and examine the role of these two relativity principles. I argue that we can hold on to (b) but that (a) is either false or trivial.
Aspects of the Italian legislation related to HIV testing
Directory of Open Access Journals (Sweden)
Stefania D'Amato
2010-03-01
Full Text Available Italy has adhered to international declarations regarding the prevention, care, and treatment of HIV/AIDS and has adopted the fundamental interventions for surveillance and control; access to testing is defined by Law 135 of 5 June 1990. At the time, the Ministry of Health issued decrees to define national epidemiological surveillance systems for new HIV infections. The decree provides indications on the data to be collected, data flow, the modes of data transmission respecting security measures and some recommendations regarding access to HIV testing. It is thus necessary to develop national recommendations on appropriate methods for considering the diverse phases of access to testing in relation to the level of awareness of the minor, the outcome and divulging of the test.
High-Order Fully General-Relativistic Hydrodynamics: new Approaches and Tests
Radice, David; Galeazzi, Filippo
2013-01-01
We present a new approach for achieving high-order convergence in fully general-relativistic hydrodynamic simulations. The approach is implemented in WhiskyTHC, a new code that makes use of state-of-the-art numerical schemes and was key in achieving, for the first time, higher than second-order convergence in the calculation of the gravitational radiation from inspiraling binary neutron stars Radice et al. (2013). Here, we give a detailed description of the algorithms employed and present results obtained for a series of classical tests involving isolated neutron stars. In addition, using the gravitational-wave emission from the late inspiral and merger of binary neutron stars, we make a detailed comparison between the results obtained with the new code and those obtained when using standard second-order schemes commonly employed for matter simulations in numerical relativity. We find that even at moderate resolutions and for binaries with large compactness, the phase accuracy is improved by a factor 50 or mo...
Zlatarić, Dubravka Knezović; Celebić, Asja
2008-01-01
This study aimed to analyze factors related to patients' general satisfaction with removable partial dentures (RPDs), such as esthetics, retention, speech, chewing, and comfort. A total of 103 patients with Kennedy Class I RPDs (34 to 82 years old; mean age: 63; 35 men, 68 women) assessed their satisfaction with dentures. Stepwise multiple regression analysis was used to evaluate the relationship among the factors. Significant correlations were found between general satisfaction and each of the individual components (P < .05). The patients' assessment of esthetics explained almost 50% of general satisfaction in both arches (P < .05). Esthetics, chewing, and speech had significant effects on the patients' general satisfaction with dentures.
Cuk, Ivan; Prebeg, Goran; Sreckovic, Sreten; Mirkov, Dragan M; Jaric, Slobodan
2017-02-01
Cuk, I, Prebeg, G, Sreckovic, S, Mirkov, DM, and Jaric, S. Generalization of muscle strength capacities as assessed from different variables, tests, and muscle groups. J Strength Cond Res 31(2): 305-312, 2017-The muscle strength capacities to exert force under various movement conditions have been indiscriminately assessed from various strength tests and variables applied on different muscles. We tested the hypotheses that the distinctive strength capacities would be revealed (H1) through different strength tests, and (H2) through different strength variables. Alternatively, (H3) all strength variables independent of the selected test could depict the same strength capacity of the tested muscle. Sixty subjects performed both the standard strength test and the test of alternating contractions of 6 pairs of antagonistic muscles acting in different leg and arm joints. The dependent variables obtained from each test and muscle were the maximum isometric force and the rate of force development. A confirmatory principle component analysis set to 2 factors explained 31.9% of the total variance. The factor loadings discerned between the tested arm and leg muscles, but not between the strength tests and variables. An exploratory analysis applied on the same data revealed 6 factors that explained 60.1% of the total variance. Again, the individual factors were mainly loaded by different tests and variables obtained from the same pair of antagonistic muscles. Therefore, a comprehensive assessment of the muscle strength capacity of the tested individual should be based on a single strength test and variable obtained from a number of different muscles, than on a single muscle tested through different tests and variables. The selected muscles should act in different limbs and joints, while the maximum isometric force should be the variable of choice.
Do out-of-office laboratory tests affect diagnoses in general practice?
Zaat, J.O.M.; Schellevis, F.G.; Eijk, J.T.M. van; Velden, K. van der
1995-01-01
OBJECTIVE: To find out whether the GP diagnosis changed by out-of-office laboratory test results and whether his diagnosis became more certain. DESIGN: Descriptive study. SETTING: Dutch survey of morbidity and interventions in general practice: stratified random sample of 161 GPs with a total list
Lack of consensus on tests and criteria for generalized joint hypermobility, Ehlers–Danlos syndrome
DEFF Research Database (Denmark)
Remvig, Lars; Flycht, Lise; Christensen, Karl Bang
2014-01-01
The objectives of this study were to register clinicians performance and opinion of importance of clinical tests for generalized joint hypermobility (GJH), Ehlers-Danlos syndrome, hypermobility type (EDS-HT) and joint hypermobility syndrome (JHS), and to reach a consensus among clinicians...
General Atomic reprocessing pilot plant: description and results of initial testing
Energy Technology Data Exchange (ETDEWEB)
1977-12-01
In June 1976 General Atomic completed the construction of a reprocessing head-end cold pilot plant. In the year since then, each system within the head end has been used for experiments which have qualified the designs. This report describes the equipment in the plant and summarizes the results of the initial phase of reprocessing testing.
General practitioners' needs for ongoing support for the interpretation of spirometry tests.
Poels, P.J.P.; Schermer, T.R.J.; Akkermans, R.P.; Jacobs, A.; Bogart-Jansen, M.; Bottema, B.J.A.M.; Weel, C. van
2007-01-01
BACKGROUND: Although one out of three general practitioners (GPs) carries out spirometry, the diagnostic interpretation of spirometric test results appears to be a common barrier for GPs towards its routine application. METHODS: Multivariate cross-sectional analysis of a questionnaire survey among
Testing among functional forms: an extension of the Generalized Box-Cox formulation.
Oude Lansink, A.G.J.M.; Thijssen, G.
1998-01-01
This paper uses the Generalized Box - Cox framework and Double Length artificial Regression to test whether different specifications of the profit function are able to mimic the technology underlying panel data of Dutch arable farms for the period 1970 - 1988. To this end, a linear GBC is developed
The Gender-Linked Language Effect: An Empirical Test of a General Process Model
Mulac, Anthony; Giles, Howard; Bradac, James J.; Palomares, Nicholas A.
2013-01-01
The gender-linked language effect (GLLE) is a phenomenon in which transcripts of female communicators are rated higher on Socio-Intellectual Status and Aesthetic Quality and male communicators are rated higher on Dynamism. This study proposed and tested a new general process model explanation for the GLLE, a central mediating element of which…
Pappas, George; Apostolatos, Theocharis A
2014-03-28
Recently, it was shown that slowly rotating neutron stars exhibit an interesting correlation between their moment of inertia I, their quadrupole moment Q, and their tidal deformation Love number λ (the I-Love-Q relations), independently of the equation of state of the compact object. In the present Letter a similar, more general, universality is shown to hold true for all rotating neutron stars within general relativity; the first four multipole moments of the neutron star are related in a way independent of the nuclear matter equation of state we assume. By exploiting this relation, we can describe quite accurately the geometry around a neutron star with fewer parameters, even if we don't know precisely the equation of state. Furthermore, this universal behavior displayed by neutron stars could promote them to a more promising class of candidates (next to black holes) for testing theories of gravity.
Social relations and loneliness among older patients consulting their general practitioner
Due, Tina Drud; Sandholdt, Håkon; Waldorff, Frans Boch
2017-01-01
INTRODUCTION: Social relations are important for people and affect their quality of life, morbidity and mortality. This holds true especially for older persons. General practitioners (GPs) are in a unique position to address social relations and loneliness; however, no GP population-based studies have assessed older patients' social relations and loneliness. The aim of this study was to analyse the social relations and loneliness of patients aged 65 years and above consulting their GP.METHODS...
Building the general relativity and gravitation community during the Cold War
Lalli, Roberto
2017-01-01
This monograph presents a new perspective on the history of general relativity. It outlines the attempts to establish an institutional framework for the promotion of the field during the Cold War. Readers will learn the difficulties that key figures experienced and overcame during this period of global conflict. The author analyzes the subtle interconnections between scientific and political factors. He shows how politics shaped the evolution of general relativity, even though it is a field with no military applications. He also details how different scientists held quite different views about what “political” meant in their efforts to pursue international cooperation. The narrative examines the specific epistemic features of general relativity that helped create the first official, international scientific society. It answers: Why did relativity bring about this unique result? Was it simply the product of specific actions of particular actors having an illuminated view of international relations in the...
Thyssen, J P; Linneberg, A; Menné, T; Nielsen, N H; Johansen, J D
2009-11-01
The prevalence of contact allergy in the general population is nearly 20%. This study aimed to monitor the development of contact allergy to allergens from the TRUE-test (panels 1 and 2) between 1990 and 2006. Two random samples of adults from the general population in Copenhagen, Denmark, were invited to participate in a general health examination including patch testing. In 1990 and 2006, we patch tested and questioned 543 and 3460 adult Danes. Patch test readings were performed on day 2 only. The overall prevalence decreased significantly from 15.5% in 1990 to 10.0% in 2006, mainly as a result of a decrease in thimerosal allergy from 3.4% to 0.8%. Furthermore, the prevalence of cobalt allergy and rubber-related allergens decreased from 1.1% to 0.2% and from 1.5% to 0.2%, respectively. Stratification by sex and age group revealed decreasing prevalences of contact allergy in all male age groups and in young and middle-aged female age groups (18-55 years) whereas increasing prevalences were observed among older women (56-69 years). The diverging trend observed in women was probably explained by a cohort effect due to a change in the prevalence of nickel allergy following the Danish regulation on nickel exposure. Although the overall prevalence of contact allergy decreased in the general population, frequent contact allergens such as fragrance mix II and methyldibromo glutaronitrile were not tested. Thus, contact allergy remains prevalent in the general population.
Differences in social relations between persons with type 2 diabetes and the general population
DEFF Research Database (Denmark)
Hempler, Nana Folmann; Ekholm, Ola; Willaing, Ingrid
2013-01-01
with type 2 diabetes. The aim of this study was to investigate whether persons with type 2 diabetes have poorer social relations than the general population. Methods: We conducted a cross-sectional survey in three settings: a specialist diabetes clinic (SDC) (n = 1084), a web panel (WP) consisting...... of persons with type 2 diabetes (n = 1491) and a sample from the 2010 Danish Health and Morbidity Survey, representative of the general population (n = 15,165). We compared social relations using multivariate logistic regression. Results: Compared to the general population, persons with type 2 diabetes more.......08-1.41). Conclusions: Our findings suggest that persons with type 2 diabetes have poorer social relations than the general population. From a public health point of view, special attention is needed with regards to strengthening existing networks and establishing alternative networks among persons with type 2 diabetes....
Variability in thyroid function test requests across general practices in south-west England.
Vaidya, Bijay; Ukoumunne, Obioha C; Shuttleworth, Joanna; Bromley, Alan; Lewis, Aled; Hyde, Chris; Patterson, Anthea; Fleming, Simon; Tomlinson, Julie
2013-01-01
The number of thyroid function tests (TFTs) performed in the UK and other countries has increased considerably in recent years. Inconsistent clinical practice associated with inappropriate requests for tests is thought to be an important cause for this increase. To study the extent of variability in requests for TFTs from general practices. We analysed routine data on all TFTs on patients aged 16 years and over carried out by two hospitals in south-west England (Royal Cornwall Hospital and Royal Devon & Exeter Hospital) during 2010 at the request of 107 general practices. A total of 195 309 TFT requests were made for 148 412 patients (63% female). The total requests included 192 108 tests for thyroid-stimulating hormone (TSH), 43 069 for free thyroxine (FT4) and 1972 for free tri-iodothyronine (FT3). The number of TSH tests per 1000 list size varied widely across the practices, ranging from 84 to 482. Most of the variation was due to heterogeneity across practices and only 24% of this was accounted for by prevalence of hypothyroidism and socio-economic deprivation. There is wide variation in TFT requests from general practice and scope to reduce both unnecessary TFTs and the variability in the clinical practice. Further studies are required to understand the causes for the variability in testing thyroid function.
Wei, Jiawei
2011-07-01
We consider the problem of testing for a constant nonparametric effect in a general semi-parametric regression model when there is the potential for interaction between the parametrically and nonparametrically modeled variables. The work was originally motivated by a unique testing problem in genetic epidemiology (Chatterjee, et al., 2006) that involved a typical generalized linear model but with an additional term reminiscent of the Tukey one-degree-of-freedom formulation, and their interest was in testing for main effects of the genetic variables, while gaining statistical power by allowing for a possible interaction between genes and the environment. Later work (Maity, et al., 2009) involved the possibility of modeling the environmental variable nonparametrically, but they focused on whether there was a parametric main effect for the genetic variables. In this paper, we consider the complementary problem, where the interest is in testing for the main effect of the nonparametrically modeled environmental variable. We derive a generalized likelihood ratio test for this hypothesis, show how to implement it, and provide evidence that our method can improve statistical power when compared to standard partially linear models with main effects only. We use the method for the primary purpose of analyzing data from a case-control study of colorectal adenoma.
Munz, S C; Costello, C T; Korabik, K
1975-01-01
The assumption that the inverted-U hypothesis, which shows performance as a function of activation level, mediates the relationship between achievement anxiety and academic test performance was tested by comparing Achievement Anxiety Test scores of 75 male and female college students with a self-report measure of activation taken prior to a classroom examination. Results supported the predicted relationship between achievement anxiety reaction type and academic performance (rho less than .05), but only partially supported the inverted-U hypothesis posited to account for this relationship. Results were further interpreted as suggesting that examinees experience two general types of arousal in the testing situationōne type that enhances performance and one that impedes performance. Further implications of the results were discussed.
Hoffman, Eric W; Pinkleton, Bruce E; Weintraub Austin, Erica; Reyes-Velázquez, Wanda
2014-01-01
Alcohol marketers have increasingly moved their advertising efforts into digital and social media venues. As a result, the purpose of this study is to investigate associations between students' use of social media, their exposure to alcohol marketing messages through social media, and their alcohol-related beliefs and behaviors. Public and private university students (N = 637) participated November and December 2011 and April 2012. College students completed online surveys to measure their exposure to social and online media generally, as well as their alcohol-related digital media use and alcohol use. Use of social media related to alcohol marketing predicted alcohol consumption and engaging in risky behaviors, whereas the use of social media more generally did not. Students' use of alcohol-related social media-marketing content associates with their problem drinking. Results have implications for alcohol abuse reduction efforts targeted at college students and suggest the importance of considering social, cultural, and cognitive factors in campaign planning and design.
Technical Issues Related to the Comprehensive Nuclear Test Ban Treaty
Garwin, Richard L.
2003-04-01
The National Academy of Sciences recently published a detailed study of technical factors related to the Comprehensive Nuclear Test Ban Treaty (CTBT), with emphasis on those issues that arose when the Senate declined to ratify the Treaty in 1999. The study considered (1) the capacity of the United States to maintain confidence in the safety and reliability of its nuclear weapons without nuclear testing; (2) the capabilities of the international nuclear-test monitoring system; and (3) the advances in nuclear weapons capabilities that other countries might make through low-yield testing that might escape detection. Excluding political factors, the committee considered three possible future worlds: (1) a world without a CTBT; (2) a world in which the signatories comply with a CTBT; and (3) a world in the signatories evade its strictures within the limits set by the detection system. The talk and ensuing discussion will elaborate on the study. The principal conclusion of the report, based solely on technical reasons, is that the national security of the United States is better served with a CTBT in force than without it, whether or not other signatories conduct low level but undetected tests in violation of the treaty. Moreover, the study finds that nuclear testing would not add substantially to the US Stockpile Stewardship Program in allowing the United States to maintain confidence in the assessment of its existing nuclear weapons.
Reeve, Charlie L.; Heggestad, Eric D.; Lievens, Filip
2009-01-01
The assessment of cognitive abilities, whether it is for purposes of basic research or applied decision making, is potentially susceptible to both facilitating and debilitating influences. However, relatively little research has examined the degree to which these factors might moderate the criterion-related validity of cognitive ability tests. To…
Levene tests of homogeneity of variance for general block and treatment designs.
O'Neill, Michael E; Mathews, Ky L
2002-03-01
This article develops a weighted least squares version of Levene's test of homogeneity of variance for a general design, available both for univariate and multivariate situations. When the design is balanced, the univariate and two common multivariate test statistics turn out to be proportional to the corresponding ordinary least squares test statistics obtained from an analysis of variance of the absolute values of the standardized mean-based residuals from the original analysis of the data. The constant of proportionality is simply a design-dependent multiplier (which does not necessarily tend to unity). Explicit results are presented for randomized block and Latin square designs and are illustrated for factorial treatment designs and split-plot experiments. The distribution of the univariate test statistic is close to a standard F-distribution, although it can be slightly underdispersed. For a complex design, the test assesses homogeneity of variance across blocks, treatments, or treatment factors and offers an objective interpretation of residual plots.
General habit propensity relates to the sensation seeking subdomain of impulsivity but not obesity
Directory of Open Access Journals (Sweden)
Anja Dietrich
2016-11-01
Full Text Available According to dual-system theory, instrumental learning and performance depend on the balance between goal-directed and habitual action control. Overreliance on habits has been argued to characterize clinical conditions such as drug addiction or obsessive-compulsive disorder as well as obesity and excessive impulsivity. A tendency towards habitual action control in obesity has already been indicated in the food domain. However, impairments might not be restricted to eating behavior. This has been suggested by domain-general obesity-associated disturbances in executive function as well as alterations in corticostriatal circuits underlying the goal-directed and habitual systems. In this study we examined the balance of goal-directed and habitual action control in a sample of normal-weight, overweight, and obese participants (n=105 using the slips-of-action test in a non-food context. We tested for continuous or group-based associations between body weight status (BMI and the devaluation sensitivity index (DSI, a parameter representing the balance of the goal-directed and habitual systems in action control. As personality differences in the domain of impulsivity might affect this relationship, we also examined whether the interaction between BMI and self-reported impulsivity, based on the UPPS Impulsive Behavior Scale, was related to the DSI. In addition to that, we tested for direct, i.e., weight status independent, relationships between UPPS subdomains of impulsivity and the DSI. We failed to find evidence for a relationship between weight status and sensitivity to devaluation as indexed by the DSI. However, independent of weight status, we observed lower sensitivity to devaluation in sensation seekers, a subtype of impulsivity. To conclude, behavioral flexibility in the sense of disturbances in the balance between the habitual and goal-directed systems seems to be unaffected by weight status in a non-food context. Consequently, stimuli and
Relational Constraint Driven Test Case Synthesis for Web Applications
Directory of Open Access Journals (Sweden)
Xiang Fu
2010-09-01
Full Text Available This paper proposes a relational constraint driven technique that synthesizes test cases automatically for web applications. Using a static analysis, servlets can be modeled as relational transducers, which manipulate backend databases. We present a synthesis algorithm that generates a sequence of HTTP requests for simulating a user session. The algorithm relies on backward symbolic image computation for reaching a certain database state, given a code coverage objective. With a slight adaptation, the technique can be used for discovering workflow attacks on web applications.
Energy Technology Data Exchange (ETDEWEB)
Ludyk, Guenter [Bremen Univ. (Germany). Physics and Electrical Engineering
2013-11-01
Derives the fundamental equations of Einstein's theory of special and general relativity using matrix calculus, without the help of tensors. Provides necessary mathematical tools in a user-friendly way, either directly in the text or in the appendices. Appendices contain an introduction to classical dynamics as a refresher of known fundamental physics. Rehearses vector and matrix calculus, differential geometry, and some special solutions of general relativity in the appendices. This book is an introduction to the theories of Special and General Relativity. The target audience are physicists, engineers and applied scientists who are looking for an understandable introduction to the topic - without too much new mathematics. The fundamental equations of Einsteins theory of Special and General Relativity are derived using matrix calculus, without the help of tensors. This feature makes the book special and a valuable tool for scientists and engineers with no experience in the field of tensor calculus. In part I the foundations of Special Relativity are developed, part II describes the structure and principle of General Relativity. Part III explains the Schwarzschild solution of spherical body gravity and examines the ''Black Hole'' phenomenon. Any necessary mathematical tools are user friendly provided, either directly in the text or in the appendices.
Platsidou, Maria; Agaliotis, Ioannis
2017-01-01
The role of empathy in the teaching profession has been vastly investigated in relation to its effect on students, but research on how teachers' empathy affects their own well-being at work is limited. This study investigated empathy and instructional assignment-related stress factors of primary school teachers serving in general or special…
General or Technical High School: Parameters Related to Greek Students' Choice
Christopoulou, Anthoula; Kounenou, Kalliope
2012-01-01
This research attempts to examine the demographic characteristics of Greek adolescents who choose either general or technical high schools as well as the parameters related to students' specific educational decision. The sample of the survey includes 198 students from both schools. Results showed that students' choice was not directly related to…
The Problem of the Particular and its Relation to the General in Mathematics Education
Font, Vicenc; Contreras, Angel
2008-01-01
Research in the didactics of mathematics has shown the importance of the problem of the particular and its relation to the general in teaching and learning mathematics as well as the complexity of factors related to them. In particular, one of the central open questions is the nature and diversity of objects that carry out the role of particular…
7 CFR 319.40-2 - General prohibitions and restrictions; relation to other regulations.
2010-01-01
... 7 Agriculture 5 2010-01-01 2010-01-01 false General prohibitions and restrictions; relation to... (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES...; relation to other regulations. (a) Permit required. Except for regulated articles exempted from this...
Garrett-Rainey, Syrena
The purpose of this study was to compare the achievement of general education students within regular education classes to the achievement of general education students in inclusion/co-teach classes to determine whether there was a significant difference in the achievement between the two groups. The school district's inclusion/co-teach model included ongoing professional development support for teachers and administrators. General education teachers, special education teachers, and teacher assistants collaborated to develop instructional strategies to provide additional remediation to help students to acquire the skills needed to master course content. This quantitative study reviewed the end-of course test (EoCT) scores of Grade 10 physical science and math students within an urban school district. It is not known whether general education students in an inclusive/co-teach science or math course will demonstrate a higher achievement on the EoCT in math or science than students not in an inclusive/co-teach classroom setting. In addition, this study sought to determine if students classified as low socioeconomic status benefited from participating in co-teaching classrooms as evidenced by standardized tests. Inferential statistics were used to determine whether there was a significant difference between the achievements of the treatment group (inclusion/co-teach) and the control group (non-inclusion/co-teach). The findings can be used to provide school districts with optional instructional strategies to implement in the diverse classroom setting in the modern classroom to increase academic performance on state standardized tests.
Subra, Julie; Chicoulaa, Bruno; Stillmunkès, André; Mesthé, Pierre; Oustric, Stéphane; Rougé Bugat, Marie-Eve
2017-12-01
The script concordance test (SCT) is a validated method of examining students' clinical reasoning. Medical students' professional skills are assessed during their postgraduate years as they study for a specialist qualification in general practice. However, no specific provision is made for assessing their clinical reasoning during their postgraduate study. The aim was to demonstrate the reliability and validity of the SCT in general practice and to determine if this tool could be used to assess medical students' progress in acquiring clinical reasoning. A 135-question SCT was administered to postgraduate medical students at the beginning of their first year of specialized training in general practice, and then every six months throughout their three-year training, as well as to a reference panel of 20 expert general practitioners. For score calculation, we used the combined scoring method as the calculator made available by the University of Montreal's School of Medicine in Canada. For the validity, student' scores were compared with experts, p <.05 was considered statistically significant. Ninety students completed all six assessments. The experts' mean score (76.7/100) was significantly higher than the students' score across all assessments (p <.001), with a Cronbach's alpha value of over 0.65 for all assessments. The SCT was found to be reliable and capable of discriminating between students and experts, demonstrating that this test is a valid tool for assessing clinical reasoning skills in general practice.
Nobili, Anna M
2016-01-01
The Universality of Free Fall and the Weak Equivalence Principle, which are at the basis of General Relativity, have been confirmed to 1 part in 10^13. Space experiments with macroscopic test masses of different composition orbiting the Earth inside a low altitude satellite aim at improving this precision by two orders of magnitude (with the Microscope satellite, launched on 25 April 2016) and up to four orders of magnitude (with the 'Galileo Galilei' - GG satellite). At such a high precision many tiny effects must be taken into account in order to be ruled out as the source of a spurious violation signal. In this work we investigate the general relativistic effects, including those which involve the rotation of both the source body and the test masses, and show that they are by far too small to be considered even in the most challenging experiment.
Life stress, anger and anxiety, and delinquency: an empirical test of general strain theory.
Aseltine, R H; Gore, S; Gordon, J
2000-09-01
General strain theory (Agnew 1992) departs from traditional strain theories by emphasizing the role of the individual's affective responses to negative life experiences in fostering deviant behavior. In this analysis, we examine the central hypotheses of general strain theory using data from a three-wave panel study of high school youths in the Boston metropolitan area (N = 939). Covariance structure models reveal that anger and hostility in response to negative life events do play a causal role in fostering more aggressive forms of delinquency, but are not significantly related to either nonaggressive delinquency or marijuana use. Furthermore, the conditional effects predicted by general strain theory, in which the impact of strain on delinquency varies by youths' personal and social resources, are inconsistent. Discussion centers on the prospect of increasing the utility of general strain theory by further imbuing it with concepts and perspectives from the sociology of mental illness.
Weingarden, Hilary; Renshaw, Keith D; Davidson, Eliza; Wilhelm, Sabine
2017-07-01
Body Dysmorphic Disorder (BDD) is characterized by a preoccupation with a perceived flaw in appearance and repetitive avoidance behaviors. BDD involves severe psychosocial outcomes (e.g., depression, suicidality, functional impairment). Identifying correlates of BDD symptoms and outcomes can inform treatment. Shame, a painful emotion felt in response to critical self-judgment, may be one key correlate. However, research on shame in BDD is scarce and previous studies have not distinguished general shame from body shame. This study examines the relative relationships between body shame and general shame with body dysmorphic phenomenology and psychosocial outcomes. Participants (N = 184) were recruited online via BDD organizations and completed a survey. Path analysis was used to examine associations between body and general shame with 1) body dysmorphic phenomenology and 2) depression severity, suicide risk, and functional impairment. Both types of shame were differentially related to outcomes. Body shame was more strongly related to phenomenology, whereas general shame was more strongly related to psychosocial outcomes. Thus, it may be important for BDD treatment to focus on reducing both general and body shame. Further research should evaluate whether current treatments adequately address and reduce general and body shame, and whether addressing shame promotes better treatment outcomes.
General health status in army personnel: relations with health behaviors and psychosocial variables.
Golenbock, Samuel; Kazman, Josh B; Krauss, Stephen; Deuster, Patricia A
2017-07-01
Poor self-rated health (SRH) is linked to an increased risk of injury, future healthcare services utilization, and morbidity and mortality. This study aimed to identify correlates of a single-item measure of health in 8070 US Army personnel. Responses were collected from the Army's global assessment tool (GAT) 2.0, an online questionnaire that assesses physical and psychosocial health. SRH was measured by the item, "How do you consider your health?" (four response categories: "poor," "fair," "good," and "excellent"). Ordinal logistic regression (OLR) was used to evaluate how various health and psychosocial factors contribute to Soldiers' ratings of SRH. Unadjusted and adjusted cumulative odds ratios (ORs) are presented and discussed. Most participants reported "good" health (57%), followed by "excellent" (24%), "fair" (17%), and "poor" (2%). Sleep quality (OR 2.48; 95% CI 2.34, 2.63) was the largest correlate of SRH, followed by obesity (OR 0.50; 95% CI 0.43, 0.58), emotional fitness (OR 1.68, 95% CI 1.56, 1.82), and Army physical fitness test (APFT) scores (OR 1.43; 95% CI 1.36, 1.51). Single-item measures of self-reported health can cover a broad spectrum across physical and mental health. Among a large US Army sample, sleep quality was most strongly associated with SRH, followed by emotional fitness and APFT scores. In contrast, service-component and other sociodemographic characteristics had relatively small effects on general health. Military investigators and leaders who must rely on various subjective general health measures should interpret them as a combination of these factors.
Deformations of the vacuum solutions of general relativity subjected to linear constraints
Molina, C.
2013-12-01
The problem of deforming geometries is particularly important in the context of constructing new exact solutions of Einstein’s equation. This issue often appears when extensions of the general relativity are treated, for instance in brane world scenarios. In this paper we investigate spacetimes in which the energy-momentum tensor obeys a linear constraint. Extensions of the usual vacuum and electrovacuum solutions of general relativity are derived and an exact solution is presented. The classes of geometries obtained include a wide variety of compact objects, among them black holes and wormholes. The general metric derived in this work generalizes several solutions already published in the literature. Perturbations around the exact solution are also considered.
Directory of Open Access Journals (Sweden)
Dragan Martinović
2011-08-01
Full Text Available Continuous monitoring of the level of motor development is one of the primary goals of teaching physical education. Gaining diversified movement experience and developing coordination is of particular importance at early school age. This is why modern approaches to teaching physical education give emphasis to the application of elements of sports games from the earliest age. Handball is a sports game which can be applied from the earliest school age because it abounds with a variety of movement tasks and includes natural forms of movement (running, jumping, throwing, etc.. Therefore, there is a great need for specific motor tests in handball. Specific motor tests are of great value, especially if observed in comparison to general motor skills results: handball requires a specific level of physical aptitude at the same timeinfluencing its further development and sustainability with its versatile contents. The specific coordination test "ball slalom" is broadly applicable and important in the overview of individual skills and can contribute to early guidance and selection in handball. That is why we tested general motor skills on a sample of 60 female students in the IV primary school grade. The testing was based on a battery of tests with the aim to find the mutual relations between these skills and the specific coordination test of "ball slalom". The aim was to check the possibilities of including a school of handball in the regular physical education curriculum.
A Broader View of Relativity General Implications of Lorentz and Poincaré Invariance
Hsu, Jong-Ping
2006-01-01
A Broader View of Relativity shows that there is still new life in old physics. The book examines the historical context and theoretical underpinnings of Einstein's theory of special relativity and describes Broad Relativity, a generalized theory of coordinate transformations between inertial reference frames that includes Einstein's special relativity as a special case. It shows how the principle of relativity is compatible with multiple concepts of physical time and how these different procedures for clock synchronization can be useful for thinking about different physical problems, includin
General tradeoff relations of quantum nonlocality in the Clauser–Horne–Shimony–Holt scenario
Energy Technology Data Exchange (ETDEWEB)
Su, Hong-Yi, E-mail: hongyisu@chonnam.ac.kr [Department of Physics Education, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Chen, Jing-Ling [Theoretical Physics Division, Chern Institute of Mathematics, Nankai University, Tianjin 300071 (China); Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore); Hwang, Won-Young, E-mail: wyhwang@jnu.ac.kr [Department of Physics Education, Chonnam National University, Gwangju 500-757 (Korea, Republic of)
2017-02-15
General tradeoff relations present in nonlocal correlations of bipartite systems are studied, regardless of any specific quantum states and measuring directions. Extensions to multipartite scenarios are possible and very promising. Tsirelson’s bound can be derived out in particular. The close connection with uncertainty relations is also presented and discussed. - Highlights: • Quantum violation of CHSH inequalities is found to satisfy tradeoff relations. • Tsirelson’s bound for quantum mechanics can be directly implied from these tradeoffs. • Tradeoff relations shed new light on uncertainty relations in summation forms.
Kurihara, Yoshimasa
2012-01-01
General characterizations of physical measurements are discussed within the framework of the classical information theory. The uncertainty relation for simultaneous measurements of two physical observables is defined in this framework for generalized dynamic systems governed by a Sturm--Liouville type of equation of motion. In the first step, the reduction of Kennard--Robertson type uncertainties due to boundary conditions with a mean-square error is discussed quantitatively with reference to...
Determinants of general practitioner's cancer-related gut feelings?a prospective cohort study
Donker, G? A; Wiersma, Eva; van der Hoek, Lucas; Heins, Marianne
2016-01-01
Background: General practitioners (GPs) use gut feelings to diagnose cancer in an early stage, but little is known about its impact. Method: Prospective cohort study of patients in 44 general practices throughout the Netherlands, from January 2010 until December 2013. GPs completed a questionnaire regarding gut feelings, patient and GP characteristics, if they noticed a cancer-related gut feeling during patient consultation. Follow-up questionnaires were sent 3 months later requesting informa...
H-theorem for nonlinear Fokker-Planck equations related to generalized thermostatistics
Frank, T. D.; Daffertshofer, A.
2001-06-01
In correspondence to conventional thermostatistics we formulate an H-theorem showing that transients solutions of nonlinear Fokker-Planck equations related to generalized thermostatistics converge to stationary probability densities. The H-theorem is applied to relaxation processes of classical bosons and fermions as proposed by Kaniadakis and Quarati, diffusion processes consistent with the generalized thermostatistics proposed by Tsallis, and stochastic processes with statistical feedback.
Longitudinal Relation Between General Well-Being and Self-Esteem.
Barendregt, Charlotte S; van der Laan, André M; Bongers, Ilja L; van Nieuwenhuizen, Chijs
2016-12-01
This study investigated the longitudinal relation between general well-being and self-esteem of male adolescents with severe psychiatric disorders. Moreover, the transition out of secure residential care was studied. Adolescents ( N = 172) were assessed three times with 6 months between each assessment. The sample comprised adolescents who were admitted throughout the entire study ( n = 116) and who had been discharged at 6/12 months follow-up ( n = 56). General well-being and self-esteem were stable concepts over time. The relation between general well-being and self-esteem differed for both groups. Among the admitted group general well-being positively predicted self-esteem and self-esteem negatively predicted general well-being from Time 2 to Time 3. Among the discharged adolescents, self-esteem at Time 1 positively predicted general well-being at Time 2 and general well-being at Time 2 positively predicted self-esteem at Time 3. Changing social contexts, as well as problems experienced during the transition out of secure care, might affect this relationship.
Gralla, Samuel E.; Lupsasca, Alexandru; Philippov, Alexander
2017-12-01
In the canonical model of a pulsar, rotational energy is transmitted through the surrounding plasma via two electrical circuits, each connecting to the star over a small region known as a “polar cap.” For a dipole-magnetized star, the polar caps coincide with the magnetic poles (hence the name), but in general, they can occur at any place and take any shape. In light of their crucial importance to most models of pulsar emission (from radio to X-ray to wind), we develop a general technique for determining polar cap properties. We consider a perfectly conducting star surrounded by a force-free magnetosphere and include the effects of general relativity. Using a combined numerical-analytical technique that leverages the rotation rate as a small parameter, we derive a general analytic formula for the polar cap shape and charge-current distribution as a function of the stellar mass, radius, rotation rate, moment of inertia, and magnetic field. We present results for dipole and quadrudipole fields (superposed dipole and quadrupole) inclined relative to the axis of rotation. The inclined dipole polar cap results are the first to include general relativity, and they confirm its essential role in the pulsar problem. The quadrudipole pulsar illustrates the phenomenon of thin annular polar caps. More generally, our method lays a foundation for detailed modeling of pulsar emission with realistic magnetic fields.
Work related stress, burnout, job satisfaction and general health of nurses: A follow-up study.
Khamisa, Natasha; Peltzer, Karl; Ilic, Dragan; Oldenburg, Brian
2016-12-01
Nurses experience high levels of work related stress and burnout as well as low job satisfaction and poor general health owing to the nature of their work. This paper seeks to provide a better understanding of the nature of relationships between work related stress, burnout, job satisfaction and general health of nurses over one year. This study involved a longitudinal design. Two hundred and seventy seven nurses from four hospitals completed a follow up survey consisting of five questionnaires. Data were collected between 2013 and 2014. The data were analysed using generalized estimation equation analysis. Lack of support was associated with burnout, patient care was associated with job satisfaction and staff issues were associated with general health of nurses. Burnout is more strongly related to job satisfaction than general health. The findings of this study could inform evidence based policy and practice through interventions aimed at improving job satisfaction and reducing the impact of burnout on general health of nurses. © 2016 John Wiley & Sons Australia, Ltd.
Criterion Related Validity of Karate Specific Aerobic Test (KSAT).
Chaabene, Helmi; Hachana, Younes; Franchini, Emerson; Tabben, Montassar; Mkaouer, Bessem; Negra, Yassine; Hammami, Mehrez; Chamari, Karim
2015-09-01
Karate is one the most popular combat sports in the world. Physical fitness assessment on a regular manner is important for monitoring the effectiveness of the training program and the readiness of karatekas to compete. The aim of this research was to examine the criterion related to validity of the karate specific aerobic test (KSAT) as an indicator of aerobic level of karate practitioners. Cardiorespiratory responses, aerobic performance level through both treadmill laboratory test and YoYo intermittent recovery test level 1 (YoYoIRTL1) as well as time to exhaustion in the KSAT test (TE'KSAT) were determined in a total of fifteen healthy international karatekas (i.e. karate practitioners) (means ± SD: age: 22.2 ± 4.3 years; height: 176.4 ± 7.5 cm; body mass: 70.3 ± 9.7 kg and body fat: 13.2 ± 6%). Peak heart rate obtained from KSAT represented ~99% of maximal heart rate registered during the treadmill test showing that KSAT imposes high physiological demands. There was no significant correlation between KSAT's TE and relative (mL/min kg) treadmill maximal oxygen uptake (r = 0.14; P = 0.69; [small]). On the other hand, there was a significant relationship between KSAT's TE and the velocity associated with VO2max (vVO2max) (r = 0.67; P = 0.03; [large]) as well as the velocity at VO2 corresponding to the second ventilatory threshold (vVO2 VAT) (r = 0.64; P = 0.04; [large]). Moreover, significant relationship was found between TE's KSAT and both the total distance covered and parameters of intermittent endurance measured through YoYoIRTL1. The KSAT has not proved to have indirect criterion related validity as no significant correlations have been found between TE's KSAT and treadmill VO2max. Nevertheless, as correlated to other aerobic fitness variables, KSAT can be considered as an indicator of karate specific endurance. The establishment of the criterion related validity of the KSAT requires further investigation.
Criterion Related Validity of Karate Specific Aerobic Test (KSAT)
Chaabene, Helmi; Hachana, Younes; Franchini, Emerson; Tabben, Montassar; Mkaouer, Bessem; Negra, Yassine; Hammami, Mehrez; Chamari, Karim
2015-01-01
Background: Karate is one the most popular combat sports in the world. Physical fitness assessment on a regular manner is important for monitoring the effectiveness of the training program and the readiness of karatekas to compete. Objectives: The aim of this research was to examine the criterion related to validity of the karate specific aerobic test (KSAT) as an indicator of aerobic level of karate practitioners. Patients and Methods: Cardiorespiratory responses, aerobic performance level through both treadmill laboratory test and YoYo intermittent recovery test level 1 (YoYoIRTL1) as well as time to exhaustion in the KSAT test (TE’KSAT) were determined in a total of fifteen healthy international karatekas (i.e. karate practitioners) (means ± SD: age: 22.2 ± 4.3 years; height: 176.4 ± 7.5 cm; body mass: 70.3 ± 9.7 kg and body fat: 13.2 ± 6%). Results: Peak heart rate obtained from KSAT represented ~99% of maximal heart rate registered during the treadmill test showing that KSAT imposes high physiological demands. There was no significant correlation between KSAT’s TE and relative (mL/min kg) treadmill maximal oxygen uptake (r = 0.14; P = 0.69; [small]). On the other hand, there was a significant relationship between KSAT’s TE and the velocity associated with VO2max (vVO2max) (r = 0.67; P = 0.03; [large]) as well as the velocity at VO2 corresponding to the second ventilatory threshold (vVO2 VAT) (r = 0.64; P = 0.04; [large]). Moreover, significant relationship was found between TE’s KSAT and both the total distance covered and parameters of intermittent endurance measured through YoYoIRTL1. Conclusions: The KSAT has not proved to have indirect criterion related validity as no significant correlations have been found between TE’s KSAT and treadmill VO2max. Nevertheless, as correlated to other aerobic fitness variables, KSAT can be considered as an indicator of karate specific endurance. The establishment of the criterion related validity of the KSAT
Generalized Einstein relation for the mutual diffusion coefficient of a binary fluid mixture.
Felderhof, B U
2017-08-21
The method employed by Einstein to derive his famous relation between the diffusion coefficient and the friction coefficient of a Brownian particle is used to derive a generalized Einstein relation for the mutual diffusion coefficient of a binary fluid mixture. The expression is compared with the one derived by de Groot and Mazur from irreversible thermodynamics and later by Batchelor for a Brownian suspension. A different result was derived by several other workers in irreversible thermodynamics. For a nearly incompressible solution, the generalized Einstein relation agrees with the expression derived by de Groot and Mazur. The two expressions also agree to first order in solute density. For a Brownian suspension, the result derived from the generalized Smoluchowski equation agrees with both expressions.
General Relativity: The most beautiful of theories. Applications and trends after 100 years
Rovelli, Carlo
2015-02-01
Generalising Newton's law of gravitation, general relativity is one of the pillars of modern physics. While applications in the beginning were restricted to isolated effects such as a proper understanding of Mercury's orbit, the second half of the twentieth century saw a massive development of applications. These include cosmology, gravitational waves, and even very practical results for satellite based positioning systems as well as different approaches to unite general relativity with another very successful branch of physics - quantum theory. On the occassion of general relativity's centennial, leading scientists in the different branches of gravitational research review the history and recent advances in the main fields of applications of the theory, which was referred to by Lev Landau as "the most beautiful of the existing physical theories".
School truancy among Turkish high school students: A test of General Strain Theory
Ozgur Solakoglu; Ugur Orak
2016-01-01
School absenteeism is a complicated problem with a variety of causes. It has been shown to be one of the main predictors of school drop-outs as well as leading to delinquency and criminal behavior in adulthood. This study examines the applicability of General Strain Theory on educational factors by considering truancy as a risk behavior. In this empirical study, we test the explanatory powers of certain kinds of strain, including school strain, economic deprivation, negative life events, ange...
Social relations and loneliness among older patients consulting their general practitioner
DEFF Research Database (Denmark)
Due, Tina Drud; Sandholdt, Håkon; Waldorff, Frans Boch
2017-01-01
Introduction: Social relations are important for people and affect their quality of life, morbidity and mortality. This holds true especially for older persons. General practitioners (GPs) are in a unique position to address social relations and loneliness; however, no GP population-based studies...... have assessed older patients’ social relations and loneliness. The aim of this study was to analyse the social relations and loneliness of patients aged 65 years and above consulting their GP. Methods: This survey counted the participation of 12 general practices in the Capital Region of Denmark....... During a three-week period, the practices invited their patients to fill out a questionnaire on health, social relations and loneliness. Results: Of 767 eligible patients, 474 were included and 461 answered one or more items about social participation or loneliness. A total of 36.2% had a high, 45...
Parallel rapid HIV testing in pregnant women at Tijuana General Hospital, Baja California, Mexico.
Viani, Rolando M; Araneta, Maria Rosario G; Spector, Stephen A
2013-03-01
The objectives of this study were to evaluate the performance of parallel rapid HIV testing and the presence of HIV-associated risk factors in pregnant women with unknown HIV status in Baja California, Mexico. Pregnant women attending the delivery unit or the prenatal clinic at Tijuana General Hospital had blood drawn for parallel rapid HIV testing with Determine™ HIV-1/2 and Uni-Gold™ Recombigen(®) HIV. The parallel rapid HIV test performance was compared to the enzyme immunoassay (EIA) and western blot. From September 2007 to July 2008, 1,383 (94%) of 1,464 women in labor and 1,992 (96%) of 2,075 women in prenatal care were enrolled. The HIV seroprevalence among women screened during labor (19/1,383, 1.37%, 95% CI: 0.85-2.18%) was significantly higher compared to those seeking prenatal care (5/1,992, 0.25%, 95% CI: 0.09-0.62%; ppositive by parallel rapid HIV testing 24 had a positive confirmatory western blot and one (0.03%) was confirmed as false positive. Additionally, two (0.06%) women had parallel rapid HIV discordant testing results; both tested negative by western blot. All women who tested negative by rapid testing had negative results on pooled EIA antibody testing. The overall sensitivity, specificity, and positive and negative predictive values of parallel rapid HIV testing were 100%, 99.9%, 96%, and 100%, respectively. These findings document a very high acceptance rate and an excellent performance of the parallel rapid HIV testing strategy during pregnancy.
The Two Extended Bodies Problem in General Relativity within the post-Newtonian Approximation
Almonacid, William
2014-01-01
The dynamics of extended bodies is a fundamental problem in any gravitational theory. In the case of General Relativity, this problem is under study since the theory was published. Several methods have been developed and different approaches are avalaible in the literature to interpret the relativistic contributions in the motion under gravity influence. The main goal in this thesis is to study a general method to face the equation of motion for extended bodies in General Relativity. We started with a proposal in the Newtonian theory, which consists in a multipolar expansion for the gravitational potentials as a function of the mass density moments and other physical variables as the stress tensor. The methodology give us the equation of motion for an isolated and self-gravitating system of extended bodies in Newtonian mechanics. A geometrical approach to get the equation of motion is also used for the Newtonian problems, it allows us to extend the methodology to General Relativity. In General Relativity, som...
Directory of Open Access Journals (Sweden)
Maryam A. Alghamdi
2014-01-01
Full Text Available We introduce the notion of generalized weaker (α-ϕ-φ-contractive mappings in the context of generalized metric space. We investigate the existence and uniqueness of fixed point of such mappings. Some consequences on existing fixed point theorems are also derived. The presented results generalize, unify, and improve several results in the literature.
Directory of Open Access Journals (Sweden)
Reem A Mustafa
Full Text Available To develop guidance on what information to include and how to present it in tables summarizing the evidence from systematic reviews of test accuracy following the Grading of Recommendations Assessment, Development and Evaluation (GRADE approach.To design and refine the evidence tables, we used an iterative process based on the analysis of data from four rounds of discussions, feedback and user testing. During the final round, we conducted one-on-one user testing with target end users. We presented a number of alternative formats of evidence tables to participants and obtained information about users' understanding and preferences.More than 150 users participated in initial discussions and provided their formal and informal feedback. 20 users completed one-on-one user testing interviews. Almost all participants preferred summarizing the results of systematic reviews of test accuracy in tabular format rather than plain text. Users generally preferred less complex tables but found presenting sensitivity and specificity estimates only as too simplistic. Users found the presentation of test accuracy for several values of prevalence initially confusing but modifying table layout and adding sample clinical scenarios for each prevalence reduced this confusion. Providing information about clinical consequences of testing result was viewed as not feasible for authors of systematic reviews.We present the current formats for tables presenting test accuracy following the GRADE approach. These tables can be developed using GRADEpro guidelines development tool (www.guidelinedevelopment.org or www.gradepro.org and are being further developed into electronic interactive tables that will suit the needs of different end users. The formatting of these tables, and how they influence result interpretation and decision-making will be further evaluated in a randomized trial.
Hyperparathyroidism-related extensor tenosynovitis at the wrist: a general review of the literature.
Ichihara, Satoshi; Hidalgo-Diaz, Juan Jose; Prunières, Guillaume; Facca, Sybille; Bodin, Frédéric; Boucher, Stéphanie; Liverneaux, Philippe
2015-07-01
Extensor tenosynovitis often occurs accompanying with rheumatoid arthritis, gout, trauma, mycobacterium and dialysis-related amyloidosis. However, there is no recognition of extensor tenosynovitis accompanying with hyperparathyroidism. The purpose of this general review was to describe the clinical condition and to report the results of surgical intervention in the extensor tenosynovitis at the wrist related to hyperparathyroidism. Hyperparathyroidism is thought to be a rare disease in adult. Although renal symptoms are the commonest symptom, musculoskeletal complaints also occur in hyperparathyroidism. From our general review, hyperparathyroidism deserves consideration in the differential diagnosis of extensor tenosynovitis at the wrist.
Torsional Newton-Cartan gravity from the large c expansion of general relativity
Van den Bleeken, Dieter
2017-09-01
We revisit the manifestly covariant large c expansion of general relativity, c being the speed of light. Assuming the relativistic connection has no pole in c-2 , this expansion is known to reproduce Newton-Cartan gravity and a covariant version of post-Newtonian corrections to it. We show that relaxing this assumption leads to the inclusion of twistless torsion in the effective non-relativistic theory. We argue that the resulting twistless torsion Newton-Cartan theory is an effective description of a non-relativistic regime of general relativity that extends Newtonian physics by including strong gravitational time dilation.
On the applicability of the geodesic deviation equation in General Relativity
Philipp, Dennis; Laemmerzahl, Claus
2016-01-01
Within the theory of General Relativity we study the solution and range of applicability of the standard geodesic deviation equation in highly symmetric spacetimes. The deviation equation is used to model satellite orbit constellations around the earth. In particular, we reconsider the deviation equation in Newtonian gravity and then determine relativistic effects within the theory of General Relativity. The deviation of nearby orbits, as constructed from exact solutions of the underlying geodesic equation, is compared to the solution of the geodesic deviation equation to assess the accuracy of the latter. Furthermore, we comment on the so-called Shirokov effect in Schwarzschild spacetime.
Extended theory of harmonic maps connects general relativity to chaos and quantum mechanism
Ren, Gang; Duan, Yi-Shi
2017-10-01
General relativity and quantum mechanism are two separate rules of modern physics explaining how nature works. Both theories are accurate, but the direct connection between two theories was not yet clarified. Recently, researchers blur the line between classical and quantum physics by connecting chaos and entanglement. Here, we showed the early reported extended HM theory that included the general relativity can also be used to recover the classic chaos equations and even the Schrodinger equation in quantum physics, suggesting the extended theory of harmonic maps may act as a universal theory of physics.
The Theological Basis of Big Bang Cosmology and the Failure of General Relativity
Crothers, Stephen J.
2013-09-01
It is shown in this paper that the Big Bang Cosmology has its basis in theology, not in science, that it pertains to a Universe entirely filled by a single spherically symmetric continuous indivisible homogeneous body and therefore models nothing, that it violates the physical principles of General Relativity, that it violates the conservation of energy, and that General Relativity itself violates the usual conservation of energy and momentum and is therefore in conflict with experiment on a deep level, rendering Einstein's conception of the physical Universe and the gravitational field invalid.
Care Model Design for E-Health: Integration of Point-of-Care Testing at Dutch General Practices
Directory of Open Access Journals (Sweden)
Bart Verhees
2017-12-01
Full Text Available Point-of-care testing (POCT—laboratory tests performed with new mobile devices and online technologies outside of the central laboratory—is rapidly outpacing the traditional laboratory test market, growing at a rate of 12 to 15% each year. POCT impacts the diagnostic process of care providers by yielding high efficiency benefits in terms of turnaround time and related quality improvements in the reduction of errors. However, the implementation of this disruptive eHealth technology requires the integration and transformation of diagnostic services across the boundaries of healthcare organizations. Research has revealed both advantages and barriers of POCT implementations, yet to date, there is no business model for the integration of POCT within general practice. The aim of this article is to contribute with a design for a care model that enables the integration of POCT in primary healthcare. In this research, we used a design modelling toolkit for data collection at five general practices. Through an iterative design process, we modelled the actors and value transactions, and designed an optimized care model for the dynamic integration of POCTs into the GP’s network of care delivery. The care model design will have a direct bearing on improving the integration of POCT through the connectivity and norm guidelines between the general practice, the POC technology, and the diagnostic centre.
Field of Genes: An Investigation of Sports-Related Genetic Testing
Wagner, Jennifer K.; Royal, Charmaine D.
2012-01-01
Sports-related genetic testing is a sector of the diverse direct-to-consumer (DTC) industry that has not yet been examined thoroughly by academic scholars. A systematic search was used to identify companies in this sector and content analysis of online information was performed. More than a dozen companies were identified. Marketing practices observed generally did not target parents for child testing, and marketing images were mild compared to images used in popular media. Information was provided at a high reading level (industry-wide Flesh-Kincaid Grade Levels > 11). While ~75% of companies provide privacy policies and terms of service prior to purchase and ~40% provide scientific citations for their tests, e-commerce generally may adequately protect DTC genetics consumers without new federal legislation or regulation. PMID:25562204
Improved test of time dilation in special relativity.
Saathoff, G; Karpuk, S; Eisenbarth, U; Huber, G; Krohn, S; Muñoz Horta, R; Reinhardt, S; Schwalm, D; Wolf, A; Gwinner, G
2003-11-07
An improved test of time dilation in special relativity has been performed using laser spectroscopy on fast ions at the heavy-ion storage-ring TSR in Heidelberg. The Doppler-shifted frequencies of a two-level transition in 7Li+ ions at v=0.064c have been measured in the forward and backward direction to an accuracy of Deltanu/nu=1 x 10(-9) using collinear saturation spectroscopy. The result confirms the relativistic Doppler formula and sets a new limit of 2.2 x 10(-7) for deviations from the time dilation factor gamma(SR)=(1-v2/c2)(-1/2).
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
A.M. Bohnen (Arthur); J. van der Lei (Johan); M.A.M. van Wijk (Marc)
1999-01-01
textabstractOBJECTIVE: To determine the consistency among the practice guidelines of the Dutch College of General Practitioners with respect to the use of blood tests. METHODS: The authors evaluated 64 practice guidelines of the Dutch College of General Practitioners.