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Gravitational constant calculation methodologies  [PDF]
V. M. Shakhparonov,O. V. Karagioz,V. P. Izmailov
Physics , 2011,
Abstract: We consider the gravitational constant calculation methodologies for a rectangular block of the torsion balance body presented in the papers Phys. Rev. Lett. 102, 240801 (2009) and Phys.Rev. D. 82, 022001 (2010). We have established the influence of non-equilibrium gas flows on the obtained values of G.
Electromagnetic waves and Stokes parameters in the wake of a gravitational wave  [PDF]
Shahen Hacyan
Physics , 2012, DOI: 10.1007/s10714-012-1434-4
Abstract: A theoretical description of electromagnetic waves in the background of a (weak) gravitational wave is presented. Explicit expressions are obtained for the Stokes parameters during the passage of a plane-fronted gravitational wave described by the Ehlers-Kundt metric. In particular, it is shown that the axis of the polarization ellipse oscillates, its ellipticity remaining constant.
Regularization parameters for the self force in Schwarzschild spacetime: II. gravitational and electromagnetic cases  [PDF]
Leor Barack,Amos Ori
Physics , 2002, DOI: 10.1103/PhysRevD.67.024029
Abstract: We obtain all ``regularization parameters'' (RP) needed for calculating the gravitational and electromagnetic self forces for an arbitrary geodesic orbit around a Schwarzschild black hole. These RP values are required for implementing the previously introduced mode-sum method, which allows a practical calculation of the self force by summing over contributions from individual multipole modes of the particle's field. In the gravitational case, we provide here full details of the analytic method and results briefly reported in a recent Letter [Phys. Rev. Lett. {\bf 88}, 091101 (2002)]. In the electromagnetic case, the RP are obtained here for the first time.
Calculation of the Universal Gravitational Constant, of the Hubble Constant, and of the Average CMB Temperature  [PDF]
Claude Mercier
Journal of Modern Physics (JMP) , 2019, DOI: 10.4236/jmp.2019.106046
Abstract: Dirac made the hypothesis that all large, dimensionless numbers that could be constructed from the important natural units of cosmology and atomic theory were connected [1] [2]. Although Dirac did not succeed in exactly matching all these numbers, he suspected that there was a way to unify all of them. Dirac’s hypothesis leads to the N constant which unifies most of physics’ parameters. It represents the maximum number of photons with a wavelength equal to the universe circumference. Using a new cosmological model, we found the β constant which represents the ratio between the expansion speed of matter in the universe and the speed of light. With these constants, we can now calculate accurately several physics parameters, including the universal gravitational constant G, the Hubble constant H0, and the average temperature T of the cosmological microwave background (CMB). Our equations show that G, H0 and T are not really constant over space and time.
Collision of arbitrary strong gravitational and electromagnetic waves in the expanding universe  [PDF]
G. A. Alekseev
Physics , 2015,
Abstract: A completely analytical model of the process of collision and nonlinear interaction of gravitational and electromagnetic soliton wave pulses and strong electromagnetic travelling waves of arbitrary profiles propagating in the expanding universe (symmetric Kasner space-time) is presented. In contrast to intuitive expectations that rather strong travelling waves can destroy the soliton, it occurs that the soliton survives during its interaction with electromagnetic wave of arbitrary amplitude and profile, but its parameters begin to evolve under the influence of this interaction. If a travelling electromagnetic wave possesses a finite duration, the soliton parameters after interaction take constant values again, but these values in general are different from those before the interaction. Based on exact solutions of Einstein - Maxwell equations, our model demonstrates a series of nonlinear phenomena, such as (a) creation of gravitational waves in the collision of two electromagnetic waves, (b) creation of electromagnetic soliton wave in the collision of gravitational soliton with travelling electromagnetic wave, (c) scattering of a part of soliton wave in the direction of propagation of travelling electromagnetic wave, (d) quasiperiodic oscillating character of fields in the wave interaction region and multiple mutual transformations of gravitational and electromagnetic waves in this region. The figures illustrate these features of nonlinear wave interactions in General Relativity.
Interaction of light with gravitational waves  [PDF]
Shahen Hacyan
Physics , 2013,
Abstract: The physical properties of electromagnetic waves in the presence of a gravitational plane wave are analyzed. Formulas for the Stokes parameters describing the polarization of light are obtained in closed form. The particular case of a constant amplitude gravitational wave is worked out explicitly.
Determinism and the gravitational Planck constant  [PDF]
Antonio Zecca
Physics , 2002,
Abstract: A discussion is given of the uncertainty principle in view of the introduction of a Gravitational Planck Constant. The need for such a gravitational constant is shown first. A reduced electromagnetic Planck constant and the analogous reduced gravitational Planck constant are defined as h/e^2 and H/m^2 respectively. An attempt is made to reconcile the quantum uncertainty concepts with a deterministic view of the physical world. This conclusion is achieved trough the detailed analysis of the measurement procedures of physical quantities.
Measurement of the gravitational constant $G$ in space (Project SEE): sensitivity to orbital parameters and space charge effect  [PDF]
A. D. Alexeev,K. A. Bronnikov,N. I. Kolosnitsyn,M. Yu. Konstantinov,V. N. Melnikov,A. J. Sanders
Physics , 2001,
Abstract: We describe some new estimates concerning the recently proposed SEE (Satellite Energy Exchange) experiment for measuring the gravitational interaction parameters in space. The experiment entails precision tracking of the relative motion of two test bodies (a heavy "Shepherd", and a light "Particle") on board a drag-free space capsule. The new estimates include (i) the sensitivity of Particle trajectories and G measurement to the Shepherd quadrupole moment uncertainties; (ii) the measurement errors of G and the strength of a putative Yukawa-type force whose range parameter \lambda may be either of the order of a few meters or close to the Earth radius; (iii) a possible effect of the Van Allen radiation belts on the SEE experiment due to test body electric charging. The main conclusions are that (i) the SEE concept may allow one to measure G with an uncertainty smaller than 10^{-7} and a progress up to 2 orders of magnitude is possible in the assessment of the hypothetic Yukawa forces and (ii) van Allen charging of test bodies is a problem of importance but it may be solved by the existing methods.
Constraining parameters of white-dwarf binaries using gravitational-wave and electromagnetic observations  [PDF]
Sweta Shah,Gijs Nelemans
Physics , 2014, DOI: 10.1088/0004-637X/790/2/161
Abstract: The space-based gravitational wave (GW) detector, \emph{evolved Laser Interferometer Space Antenna} (eLISA) is expected to observe millions of compact Galactic binaries that populate our Milky Way. GW measurements obtained from the eLISA detector are in many cases complimentary to possible electro-magnetic (EM) data. In our previous papers, we have shown that the EM data can significantly enhance our knowledge of the astrophysically relevant GW parameters of the Galactic binaries, such as the amplitude and inclination. This is possible due to the presence of some strong correlations between GW parameters that are measurable by both EM and GW observations, for example the inclination and sky position. In this paper, we quantify the constraints in the physical parameters of the white-dwarf binaries, i.e. the individual masses, chirp mass and the distance to the source that can be obtained by combining the full set of EM measurements such as the inclination, radial velocities, distances and/or individual masses with the GW measurements. We find the following $2-\sigma$ fractional uncertainties in the parameters of interest. The EM observations of distance constrains the the chirp mass to $\sim 15-25 %$, whereas EM data of a single-lined spectroscopic binary constrains the secondary mass and the distance with factors of 2 to $\sim 40 %$. The single-line spectroscopic data complemented with distance constrains the secondary mass to $\sim 25-30%$. Finally EM data on double-lined spectroscopic binary constrains the distance to $\sim 30%$. All of these constraints depend on the inclination and the signal strength of the binary systems. We also find that the EM information on distance and/or the radial velocity are the most useful in improving the estimate of the secondary mass,inclination and/or distance.
The scaling evolution of cosmological constant  [PDF]
Ilya L. Shapiro,Joan Sola
Physics , 2000, DOI: 10.1088/1126-6708/2002/02/006
Abstract: In quantum field theory the parameters of the vacuum action are subject to renormalization group running. In particular, the ``cosmological constant'' is not a constant in a quantum field theory context, still less should be zero. In this paper we continue with previous work, and derive the particle contributions to the running of the cosmological and gravitational constants in the framework of the Standard Model in curved space-time. At higher energies the calculation is performed in a sharp cut off approximation. We assess, in two different frameworks, whether the scaling dependences of the cosmological and gravitational constants spoil primordial nucleosynthesis. Finally, the cosmological implications of the running of the cosmological constant are discussed.
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