The Supernova Cosmology Project is comparing the amount of expansion over billions of years to that over shorter more recent periods of time, pinpointing the change in the rate of expansion. The preliminary results are in and they indicate that the universe appears to be slowing down. Additional data will reveal a more precise picture of the future. Perlmutter says when his team has data on 100 supernovae, then they will be able to accurately project the future rate of slowdown. To understand Omega, you must enter the world of mathematics.
Omega is the average density of mass in the entire universe.
Long a matter of study, it remains the unknown value in an equation for the fate of the universe. Learn the value of Omega and you will know whether or not the universe lasts forever. However, the rate at which the universe is slowing down is directly related to the average mass density of the universe. Thus, the Supernova Cosmology Project is on the verge of deducing Omega. As Perlmutter explains, matter is the source of gravity.