Dark matter and dark energy. Together they compose over 95% of the stuff in the universe. Observations conclusively demonstrate that both exist. Yet scientists have little idea what they actually are. The completion of the Large Hadron Collider excites hope that particle physicists might create some dark matter in the lab. Until then, astronomical observations provide the only means to probe this mysterious phenomenon.
Some recent observations indicate that scientists are on the right track in understanding how dark matter behaves on cosmological scales. Because the mass of dark matter in the universe is about five times larger than ordinary matter, it dominates the gravitational interactions that lead to galaxy and galaxy cluster formation as the universe develops. If the prevailing Lambda-Cold Dark Matter big bang model is correct, the dark matter condensed into long filaments as the universe cooled from its hot, uniform state when the cosmic microwave background radiation was emitted. Galaxies and galaxy clusters typically formed at the intersection of these filaments.
Using a large survey of galaxies observed with the Canada-France-Hawaii Telescope, an international team of astronomers mapped out dark matter filaments spanning over 270 million light years. For comparison, the Milky Way Galaxy is roughly 30,000 light-years across and the Andromeda Galaxy is only 2 million light-years away. In all likelihood, the filaments are even larger because the region surveyed by the telescope limits the size of the filaments the astronomers could detect.
Not only did the scientists find the expected filamentary structure for the dark matter, they also measured the amount of dark matter in the universe based on the survey. Their number of 25% matches the value determined from analysis of the cosmic microwave background by WMAP.
This “match” affirms that scientists’ understanding of the universe, including its formation via the big bang, is correct. Big bang cosmology provides powerful support for the God of the Bible. Therefore, RTB is delighted that ever-more detailed tests continue to confirm its validity.