If the fate of the universe were determined solely by what is currently known to
ID: 1615405 • Letter: I
Question
If the fate of the universe were determined solely by what is currently known to be the total mass of the universe in luminous and dark matter (excluding dark energy), astronomers would predict that we live in a universe that will a. expand forever. b. slow its expansion but never reverse it. c. stop expanding and eventually collapse. d. oscillate between expansion and collapse. e. expand so quickly that it will rip apart. Gravity acts to _____ the expansion of the universe, and dark energy acts to _____ the expansion. a. slow down: slow down b. slow down; speed up c. speed up; slow down d. speed up; speed up To determine how the expansion rate of the universe has changed over time, astronomers directly measure the _____ for a sample of Type la supernovae in distant galaxies. a. redshift and luminosity b. redshift and brightness c. redshift and distance d. distance and luminosity e. distance and brightness The observations that show that the expansion of the universe is speeding up tell us the universe must contain a. gravity b. dark matter. c. a force opposing gravity. d black holes. e. cosmic microwave background radiation. In a closed (spherical) universe, the sum of the angles in a triangle is a. 180 degrees. b. 180 degrees. e. 240 degrees. 6. The accelerated expansion of the universe was observationally discovered using a. Type la supernovae. b. Cepheid variables. c. RR Lyrae. d. parallax. e. colors of galaxies.Explanation / Answer
1) option b is correct.
Dark energy causes rapid expansion and dark matter hold together. If wanted the Universe to have the same exact amount of matter in it, but with no dark energy, our Universe would have expanded faster early on, and would be expanding slower today.