2,832 research outputs found
The Consistent Newtonian Limit of Einstein's Gravity with a Cosmological Constant
We derive the `exact' Newtonian limit of general relativity with a positive
cosmological constant . We point out that in contrast to the case with
, the presence of a positive in Einsteins's equations
enforces, via the condition , on the potential , a range
, within which the
Newtonian limit is valid. It also leads to the existence of a maximum mass,
. As a consequence we cannot put the boundary
condition for the solution of the Poisson equation at infinity. A boundary
condition suitably chosen now at a finite range will then get reflected in the
solution of provided the mass distribution is not spherically symmetric.Comment: Latex, 15 pages, no figures, errors correcte
About the propagation of the Gravitational Waves in an asymptotically de-Sitter space: Comparing two points of view
We analyze the propagation of gravitational waves (GWs) in an asymptotically
de-Sitter space by expanding the perturbation around Minkowski and introducing
the effects of the Cosmological Constant (), first as an additional
source (de-Donder gauge) and after as a gauge effect (-gauge). In both
cases the inclusion of the Cosmological Constant impedes the
detection of a gravitational wave at a distance larger than
, where
and f and are the frequency and
strain of the wave respectively. We demonstrate that is just a
confirmation of the Cosmic No hair Conjecture (CNC) already explained in the
literature.Comment: Accepted for publication in MPL
- …