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Hubble’s Constant  [PDF]
Angel Fierros Palacios
Journal of High Energy Physics, Gravitation and Cosmology (JHEPGC) , 2016, DOI: 10.4236/jhepgc.2016.23025
Abstract: An analytical method to calculate Hubble’s constant [1] is presented. The proposed procedure is an alternative scheme to the red shifts of spectral lines picture, to obtain the value of that constant [2].
The redshift in Hubble's constant  [PDF]
M. Temple-Raston
Physics , 1995,
Abstract: A generalisation to electrodynamics and Yang-Mills theory is presented that permits computation of the speed of light. The model presented herewithin indicates that the speed of light in vacuo is not a universal constant. This may be relevant to the current debate in astronomy over large values of the Hubble constant obtained through the use of the latest generation of ground and space-based telescopes. An experiment is proposed based on Compton scattering to measure deviations in the speed of light.
Light Dragging, the Origin of Hubble's Constant  [PDF]
Walter J. Christensen Jr
Physics , 2008,
Abstract: Recently E. Harrison has argued the Red Shift distance law proposed by Hubble and velocity-distance law developed later on theoretical grounds has no general proof demonstrating the two laws are actually equivalent. It is the purpose of this paper to account for the nebular redshift law of Hubble based on two principles: 1) Spacetime motion and light dragging. 2) An overall spacetime index of refraction based on Hubble's Constant.
Measuring Hubble's Constant in our Inhomogeneous Universe  [PDF]
Xiangdong Shi,Lawrence M. Widrow,L. Jonathan Dursi
Physics , 1995, DOI: 10.1093/mnras/281.2.565
Abstract: Recent observations of Cepheids in the Virgo cluster have bolstered the evidence that supports a Hubble constant in 70-90 km/s/Mpc range. This evidence, by and large, probes the expansion of the Universe within 100 Mpc. We investigate the possibility that the expansion rate within this region is systematically higher than the true expansion rate due to the presence of a local, large underdense region or void. We begin by calculating the expected deviations between the locally measured Hubble constant and the true Hubble constant for a variety of models. We also discuss the expected correlations between these deviations and mass fluctuation for the sample volume. We find that the fluctuations are small for the standard cold dark matter as well as mixed dark matter models but can be substantial in a number of interesting and viable nonstandard scenarios. However, deviations in the Hubble flow for a region of radius 200 Mpc are small for virtually all reasonable models. Therefore, methods based on supernovae or the Sunyaev-Zel'dovich effect, which can probe 200 Mpc scales, will be essential in determining the true Hubble constant. We discuss, in detail, the fluctuations induced in the cosmic background radiation by voids at the last scattering surface. In addition, we discuss the dipole and quadrupole fluctuations one would expect if the void enclosing us is aspherical or if we lie off-center.
The Pioneer's acceleration anomaly and Hubble's constant  [PDF]
J. L. Rosales
Physics , 2002,
Abstract: The reported anomalous acceleration acting on the Pioneers spacecrafts could be seen as a consequence of the existence of some local curvature in light geodesics when using the coordinate speed of light in an expanding space-time. The effect is related with the non synchronous character of the underlying metric and therefore, planets closed orbits can not reveal it. It is shown that the cosmic expansion rate -the Hubble parameter H- has been indeed detected. Additionally, a relation for an existing annual term is obtained which depends on the cosine of the ecliptic latitude of the spacecraft, suggestingan heuristic analogy between the effect and Foucault's experiment - light rays playing a similar role in the expanding space than Foucault's Pendulum does while determining Earth's rotation. This statement could be seen as a benchmark for future experiments.
The variation of the gravitational constant inferred from the Hubble diagram of Type Ia supernovae  [PDF]
E. Garcia-Berro,Yu. A. Kubyshin,P. Loren-Aguilar,J. Isern
Physics , 2005, DOI: 10.1142/S0218271806008772
Abstract: We consider a cosmological model with a variable gravitational constant, G, based on a scalar-tensor theory. Using the recent observational data for the Hubble diagram of type Ia supernovae (SNeIa) we find a phenomenological expression describing the variation of G. The corresponding variation of the fine structure constant \alpha within multidimensional theories is also computed and is shown not to support known constraints on \Delta \alpha / \alpha.
The Hubble parameter in the early universe with viscous QCD matter and finite cosmological constant  [PDF]
A. Tawfik
Physics , 2011, DOI: 10.1002/andp.201100038
Abstract: The evolution of a flat, isotropic and homogeneous universe is studied. The background geometry in the early phases of the universe is conjectured to be filled with causal bulk viscous cosmological fluid and dark energy. The energy density relations obtained from the assumption of covariant conservation of energy-momentum tensor of the background matter in the early universe are used to derive the basic equation for the Hubble parameter $H$. The viscous properties described by ultra-relativistic equations of state and bulk viscosity taken from recent heavy-ion collisions and lattice QCD calculations have been utilized to give an approximate solution of the field equations. The cosmological constant is conjectured to be related to the energy density of the vacuum. In this treatment, there is a clear evidence for singularity at vanishing cosmic time $t$ indicating the dominant contribution from the dark energy. The time evolution of $H$ seems to last for much longer time than the ideal case, where both cosmological constant and viscosity coefficient are entirely vanishing.
Planck Constant as Adiabatic Invariant Characterized by Hubble’s and Cosmological Constants  [PDF]
Anton Lipovka
Journal of Applied Mathematics and Physics (JAMP) , 2014, DOI: 10.4236/jamp.2014.25009
Abstract:

Within the framework of Einstein-Cartan-Shr?dinger formalism with asymmetric connections, the Planck constant is calculated from the first principles (from geometry of our Universe), as the adiabatic invariant of electromagnetic field on the Riemann-Cartan manifold. The Planck constant, calculated with actually measured cosmological parameters, coincide with that one, measured in laboratory with precision up to the second digit. The non-local generalization of quantum theory is suggested. The fundamental sense of the Quantum Theory is discussed, and physical sense of the cosmological constant is revealed. Within the mentioned framework, the quantum theory is naturally unified with gravity.

Using a Kinematic Definition of the Hubble Parameter to Determine the Cosmological Constant Λ = 0 in a Balanced Universe  [PDF]
David Savickas
Physics , 2011, DOI: 10.1142/S0217732313300255
Abstract: The Hubble parameter is kinematically defined in terms of the positions and velocities of all particles in a universe which may or may not be finite. This definition is set equal to the Hubble parameter as defined in the Friedman-Lema\^itre solution of general relativity, and which occurs after the inflationary expansion has ended in the Guth model. Because a coordinate system at rest relative to its local Hubble drift is a system in which the cosmic background radiation is observed to be isotropic, it is also an inertial system. Just before the first mass particles are created within a pure radiation universe, there are no mass particles that exist which can define H or the inertial systems associated with the Hubble drift. It will be shown that only a cosmological constant with a magnitude of zero will allow radiation to form mass particles that have a total energy which is independent of inertial systems and is equal to the equivalent energy of their rest mass. Additional mass particles are continuously formed from the radiation throughout the expanding universe after the initial particles are created.
Constraints on Hubble's Constant, Omega_baryon and Lambda from Cosmic Microwave Background Observations  [PDF]
Charles H. Lineweaver,Domingos Barbosa,Alain Blanchard,James G. Bartlett
Physics , 1996,
Abstract: In this paper we compare data to theory. We use a compilation of the most recent cosmic microwave background (CMB) measurements to constrain Hubble's constant h, the baryon fraction Omega_b, and the cosmological constant lambda. We fit h-, Omega_b- and lambda-dependent power spectra to the data. The models we consider are flat cold dark matter (CDM) dominated universes with flat (n=1) power spectra, thus the results obtained apply only to these models. CMB observations can exclude more than half of the h - Omega_b parameter space explored. The CMB data favor low values of Hubble's constant; h \approx 0.35. Low values of Omega_b are preferred (Omega_b ~ 0.03) but the chi-squared minimum is shallow and we obtain Omega_b < 0.28. A model with h \approx 0.40, Omega_b \approx 0.15 and Omega_CDM \approx 0.85 is permitted by constraints from the CMB data, BBN, cluster baryon fractions and the shape parameter Gamma derived from the mass density power spectra of galaxies and clusters. For flat-lambda models, the CMB data, combined with BBN constraints exclude most of the h - lambda plane. Models with Omega_o \approx 0.3, lambda \approx 0.7 with h \approx 0.75 are fully consistent with the CMB data but are excluded by the strict new q_{o} limits from supernovae (Perlmutter et al. 1996). A combination of CMB data goodness-of-fit statistics, BBN and supernovae constraints in the h-lambda plane, limits Hubble's constant to the interval 0.23 < h < 0.72.
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