1,146 research outputs found
Viscous Dark Energy Models with Variable G and Lambda
We consider a cosmological model with bulk viscosity () and variable
cosmological ) and
gravitational () constants. The model exhibits many interesting cosmological
features. Inflation proceeds du to the presence of bulk viscosity and dark
energy without requiring the equation of state . During the
inflationary era the energy density () does not remain constant, as in
the de-Sitter type. Moreover, the cosmological and gravitational constants
increase exponentially with time, whereas the energy density and viscosity
decrease exponentially with time. The rate of mass creation during inflation is
found to be very huge suggesting that all matter in the universe was created
during inflation.Comment: 6 Latex page
A New Formulation of Electrodynamics
A new formulation of electromagnetism based on linear differential commutator
brackets is developed. Maxwell equations are derived, using these commutator
brackets, from the vector potential , the scalar potential and
the Lorentz gauge connecting them. With the same formalism, the continuity
equation is written in terms of these new differential commutator brackets.
Keywords: Mathematical formulation, Maxwell's equationsComment: 11 Latex pages, no figure
The Universe With Bulk Viscosity
Exact solutions for a model with variable , and bulk viscosity
are obtained. Inflationary solutions with constant (de Sitter-type) and
variable energy density are found. An expanding anisotropic universe is found
to isotropize during its course of expansion but a static universe is not. The
gravitational constant is found to increase with time and the cosmological
constant decreases with time as .Comment: 7 LateX pages, no figure
- …