My, what big ears you have!
If observations are correct, this higher-than-expected value for the Hubble constant would pose serious questions for large portions of the standard model of the Universe. Known as the Lambda Cold Dark Matter (Lambda CDM) model, this idea predicts the makeup of all of the matter and energy in the Universe — ordinary matter, dark matter, and dark energy. (Lambda refers to Einstein’s cosmological constant, representing dark energy.)
This framework also provides our basic understanding of the evolution of the Universe since the Big Bang. The video below shows Professor Wendy Freedman looks at the conundrum posed by differing values of the Hubble constant.
Examining galaxies with water-bearing molecular gas, astronomers focused their sights on supermassive black holes near the centers of these stars. Those galaxies which spin in such as fashion that they are seen nearly edge-on as seen from Earth produce emissions called masers, similar to large, naturally-produced lasers of radio waves. When these waves pass around a massive object, the light is effected in a way that can be analyzed to produce accurate measurements of the Hubble constant.
Astronomers set their sights on four galaxies, found between 168 and 431 million light years from Earth. They set some of the world’s most powerful radio telescopes in the search for maser radiation, including the Very Long Baseline Array (VLBA), Karl G. Jansky Very Large Array (VLA), and Robert C. Byrd Green Bank Telescope (GBT), along with the Effelsberg telescope in Germany.
When the study was complete, researchers reached roughly the same value as most experimental data — 73.9 km/sec/Mpc.
Science is, ideally, based on balancing the predictions of theory against the reality of experiment. This latest study could lend further evidence to the idea that the standard model of the Universe may need a significant new interpretation.
This article was originally published on The Cosmic Companion by James Maynard, founder and publisher of The Cosmic Companion. He is a New England native turned desert rat in Tucson, where he lives with his lovely wife, Nicole, and Max the Cat. You can read this original piece here.
Astronomy News with The Cosmic Companion is also available as a weekly podcast, carried on all major podcast providers. Tune in every Tuesday for updates on the latest astronomy news, and interviews with astronomers and other researchers working to uncover the nature of the Universe.
