The same mystery force that is speeding up the expansion of the universe is also stunting the growth of the objects inside it. After bulking up rapidly in the first 10 billion years of cosmic time, clusters of galaxies, the cloud like swarms that are the largest conglomerations of matter in the universe, have grown anemically or not at all during the last five billion years, like sullen teenagers who suddenly refuse to eat.
This result could be explained as arrested development of the universe. This stifling of growth is the unmistakable signature of an anti-gravitational force that astronomers have labeled dark energy. It was discovered 10 years ago by astronomers who were using exploding stars called supernovas as distance markers to chart the expansion of the universe. They found that instead of slowing down because of cosmic gravity, as common sense would suggest, the expansion of the universe was actually speeding up, with galaxies zooming apart faster and faster.
This result could be explained as arrested development of the universe. This stifling of growth is the unmistakable signature of an anti-gravitational force that astronomers have labeled dark energy. It was discovered 10 years ago by astronomers who were using exploding stars called supernovas as distance markers to chart the expansion of the universe. They found that instead of slowing down because of cosmic gravity, as common sense would suggest, the expansion of the universe was actually speeding up, with galaxies zooming apart faster and faster.
0 comments:
Post a Comment