130 research outputs found
Conformally coupled dark matter
Dark matter is obtained from a scalar field coupled conformally to
gravitation; the scalar being a relict of Dirac's gauge function. This
conformally coupled dark matter includes a gas of very light () neutral bosons having spin 0, as well as a
time-dependent global scalar field, both pervading all of the cosmic space. The
time-development of this dark matter in the expanding F-R-W universe is
investigated, and an acceptable cosmological behaviour is obtained.Comment: LaTEX File 10 pages, no figure
A Weyl-Dirac Cosmological Model with DM and DE
In the Weyl-Dirac (W-D) framework a spatially closed cosmological model is
considered. It is assumed that the space-time of the universe has a chaotic
Weylian microstructure but is described on a large scale by Riemannian
geometry. Locally fields of the Weyl connection vector act as creators of
massive bosons having spin 1. It is suggested that these bosons, called
weylons, provide most of the dark matter in the universe. At the beginning the
universe is a spherically symmetric geometric entity without matter. Primary
matter is created by Dirac's gauge function very close to the beginning. In the
early epoch, when the temperature of the universe achieves its maximum,
chaotically oriented Weyl vector fields being localized in micro-cells create
weylons. In the dust dominated period Dirac's gauge function is giving rise to
dark energy, the latter causing the cosmic acceleration at present. This
oscillatory universe has an initial radius identical to the Plank length =
1.616 exp (-33) cm, at present the cosmic scale factor is 3.21 exp (28) cm,
while its maximum value is 8.54 exp (28) cm. All forms of matter are created by
geometrically based functions of the W-D theory.Comment: 25 pages. Submitted to GR
Creation of fundamental particles in Wesson's IMT
Fundamental particles, regarded as the constituents of quarks and leptons,
are described classicaly in the framework of the Weyl-Dirac version of Wesson's
Induced Matter Theory. There are neutral particles and particles having charge
Q=+/-(1/3e). The particles appear on the 4D brane, our universe, and are filled
with a substance induced by the 5D bulk. This substace is taken to have mass
density, charge density, pressure and is characterized by the prematter eq. of
state P+\rho=0. The interior is separated from the surrounding vacuum by a
boundary surface where the 4D metric tensor satisfies an a'la Schwarzschild
condition. Outside of the boundary holds the Schwarzschild, or the
Reissner-Nordstroem Metric, while the particles are characterized by mass,
radius, charge.Comment: 29 pages. Submitted for publication in the Gen. Rel. and Grav.
Journa
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