SLAS Regular Meeting
Friday, November 21, 2014 7:30pm
Dark Matter, Dark Energy, and
the Accelerating Universe
Dr. Bharat Ratra
Kansas State University
Scientists have discovered that most of the
material in the universe is invisible – it neither
emits light nor reflects light, so they
call it "dark matter". They have also discovered
a strange force that is causing the universe
to expand ever faster. The force is apparently
due to an unknown phenomenon,
which they have called "dark energy". Dr.
Ratra will describe the astronomical data
that persuades cosmologists that the dark
energy and dark matter, whatever they turn
out to be, are by far the main components of
the universe at this time. He will also explain
how these observations have led to the
development of a detailed "standard" model
of cosmology. This model describes how
the universe has evolved from a small speck
at an unimaginably short time after the Big
Bang to the immense and complex structures
of the cosmos that we see almost fourteen
billion years later.
Dr. Ratra is a Professor of Physics at Kansas
State University. His research interests involve
cosmology and astroparticle physics.
He studies the structure and evolution of the
universe by devising computer models.
These models predict the distribution of
matter and energy of the present universe
from points in time after its beginning. He
then compares the results of the models to
the observed universe of today.
December: Lunar and Solar Eclipse Photography
Introduction of Officers
Announcements and Star Parties