

The isotropic and homogeneous FLRW cosmological model has been so
successful in describing the observable Universe that it is
commonly referred to as the ``standard model''. Furthermore, and
to its credit, the model is relatively simple; it allows for
calculations and predictions to be made of the very early
Universe, including primordial nucleosynthesis at
seconds after the Big Bang, and even particle interactions
approaching the Planck scale at
seconds. At present, observational support for the standard
model includes:
-
the expansion of the Universe
as verified by the redshifts in galaxy spectra and quantified
by measurements of the Hubble constant
km sec
Mpc
with Hubble parameter 0.5<
h
<1;
-
the deceleration parameter
observed in distant galaxy spectra (although uncertainties
about galactic evolution, intrinsic luminosities, and standard
candles prevent even a crude estimate);
-
the large scale isotropy and homogeneity of the Universe
based on temperature anisotropy measurements of the microwave
background radiation and peculiar velocity fields of galaxies
(although the light distribution from bright galaxies seems
more tenuous);
-
the age of the Universe
which yields roughly consistent estimates between the
look-back time to the Big Bang in the FLRW model and observed
data such as the oldest stars, radioactive elements, and
cooling of white dwarf stars;
-
the cosmic microwave background radiation
suggests that the Universe began from a hot Big Bang and the
data is consistent with a black body at temperature 2.7 K;
-
the abundance of light elements
such as
H,
He,
He and
Li, as predicted from the FLRW model, are consistent with
observations and provides a bound on the baryon density and
baryon-to-photon ratio;
-
the present mass density, as determined from measurements of luminous matter and
galactic rotation curves, can be accounted for by the FLRW
model with a single density parameter
to specify the metric topology;
-
the distribution of galaxies and larger scale structures
can be reproduced by numerical simulations in the context of
inhomogeneous perturbations of the FLRW models.
Because of these successes, most work in the field of physical
cosmology (see §
4) has utilized the standard model as the background spacetime in
which the large scale structure evolves, with the ambition to
further constrain the cosmological parameters and structure
formation scenarios through numerical simulations. The reader is
referred to [34
] for a more in-depth review of the standard model.


|
Computational Cosmology: from the Early Universe to the
Large Scale Structure
Peter Anninos
http://www.livingreviews.org/lrr-1998-9
© Max-Planck-Gesellschaft. ISSN 1433-8351
Problems/Comments to
livrev@aei-potsdam.mpg.de
|