1,498 research outputs found
Finite bounded expanding white hole universe without dark matter
The solution of Einstein's field equations in Cosmological General Relativity
(CGR), where the Galaxy is at the center of a finite yet bounded spherically
symmetrical isotropic gravitational field, is identical with the unbounded
solution. This leads to the conclusion that the Universe may be viewed as a
finite expanding white hole. The fact that CGR has been successful in
describing the distance modulus verses redshift data of the high-redshift type
Ia supernovae means that the data cannot distinguish between unbounded models
and those with finite bounded radii of at least . Also it is shown that
the Universe is spatially flat at the current epoch and has been at all past
epochs where it was matter dominated.Comment: 11 pages, revised versio
Spheroidal and elliptical galaxy radial velocity dispersion determined from Cosmological General Relativity
Radial velocity dispersion in spheroidal and elliptical galaxies, as a
function of radial distance from the center of the galaxy, has been derived
from Cosmological Special Relativity. For velocity dispersions in the outer
regions of spherical galaxies, the dynamical mass calculated for a galaxy using
Carmelian theory may be 10 to 100 times less than that calculated from standard
Newtonian physics. This means there is no need to include halo dark matter. The
velocity dispersion is found to be approximately constant across the galaxy
after falling from an initial high value at the center.Comment: 10 pages, 3 figure
The vector algebra war: a historical perspective
There are a wide variety of different vector formalisms currently utilized in
engineering and physics. For example, Gibbs' three-vectors, Minkowski
four-vectors, complex spinors in quantum mechanics, quaternions used to
describe rigid body rotations and vectors defined in Clifford geometric
algebra. With such a range of vector formalisms in use, it thus appears that
there is as yet no general agreement on a vector formalism suitable for science
as a whole. This is surprising, in that, one of the primary goals of nineteenth
century science was to suitably describe vectors in three-dimensional space.
This situation has also had the unfortunate consequence of fragmenting
knowledge across many disciplines, and requiring a significant amount of time
and effort in learning the various formalisms. We thus historically review the
development of our various vector systems and conclude that Clifford's
multivectors best fulfills the goal of describing vectorial quantities in three
dimensions and providing a unified vector system for science.Comment: 8 pages, 1 figure, 1 tabl
Carmeli's accelerating universe is spatially flat without dark matter
Carmeli's 5D brane cosmology has been applied to the expanding accelerating
universe and it has been found that the distance redshift relation will fit the
data of the high-z supernova teams without the need for dark matter. Also the
vacuum energy contribution to gravity indicates that the universe is
asymptotically expanding towards a spatially flat state, where the total
mass/energy density tends to unity.Comment: 4 pages, 5 figures, accepted for publication in Int. J. Theor.
Physics, this paper is based on an invited talk at FFP6, Udine, Italy, Sept
200
Determination of stability constants using genetic algorithms
A genetic algorithm (GA)-simplex hybrid approach has been developed for the determination of stability constants using calorimetric and polarographic data obtained from literature sources. The GA determined both the most suitable equilibrium model for the systems studied and the values of the stability constants and the heats of formation for the calorimetric studies. As such, a variable length chromosome format was devised to represent the equilibrium models and stability constants (and heats of formation). The polarographic data were obtained from studies of cadmium chloride and lead with the crown ether dicyclohexyl-18-crown-6. The calorimetric data were obtained from a study of a two step addition reaction of Hg(CN)2 with thiourea. The stability constants obtained using the GA-simplex hybrid approach compare favourably with the values quoted in the literature
Generalised Minkowski spacetime
The four dimensional spacetime continuum, as first conceived by Minkowski,
has become the default framework within which to describe physical laws. In
this paper, we show how a four-dimensional Minkowski spacetime structure
naturally arises from three-dimensional physical space when modeled with
Clifford geometric algebra . This expanded eight-dimensional
framework allows a generalisation of the invariant interval and the Lorentz
transformations. Also, with this geometric oriented approach the fixed speed of
light, the laws of special relativity and the form of Maxwell's equations,
arise naturally from the intrinsic properties of the algebra without recourse
to physical arguments. We also find new insights into the nature of time, a
unified treatment of energy-momentum and spin, a Lagrangian unifying gravity
and electromagnetism as well as predictions of a new class of physical effects
and interactions.Comment: 20 pages, no figure
Modified permittivity observed in bulk Gallium Arsenide and Gallium Phosphide samples at 50 K using the Whispering Gallery mode method
Whispering Gallery modes in bulk cylindrical Gallium Arsenide and Gallium
Phosphide samples have been examined both in darkness and under white light at
50 K. In both samples we observed change in permittivity under light and dark
conditions. This results from a change in the polarization state of the
semiconductor, which is consistent with a free electron-hole
creation/recombination process. The permittivity of the semiconductor is
modified by free photocarriers in the surface layers of the sample which is the
region sampled by Whispering Gallery modes.Comment: 8 pages, 3 figure
- …