Astrophysicists From The eBOSS Project Have Created The Largest Three-Dimensional Map Of The Universe
Astrophysicists from the eBOSS international project have published the largest and most detailed three-dimensional map of the Universe yet. It includes more than two million galaxies and covers a distance of 11 billion light-years from Earth, according to the press service of the SDSS project, of which eBOSS is a part.
"We know quite well both the ancient and recent history of the expansion of the Universe, but in the middle, there was a gap of 11 billion years. We have been filling this gap for the past five years. [We are confident that] this information will become the basis for the most significant discoveries in cosmology over the past decade," commented Kyle Dawson, head of eBOSS, a cosmologist at the University of Utah.
The eBOSS (extended Baryon Oscillation Spectroscopic Survey) project is part of the SDSS (Sloane digital sky survey) international survey. As part of this project, astrophysicists are studying so-called Baryon Acoustic Oscillations (BAO) using the instruments of the Apache point Observatory (new Mexico, USA).
As cosmologists suggest, BAOS are giant acoustic waves, a kind of" echo " of the Big Bang. They spread throughout the Universe in the first epochs of its existence and left characteristic traces in the form of an uneven distribution of matter through its thickness. Scientists are trying to learn the properties of these waves by observing how the Universe works in three-dimensional form.
White spots on the map of the Universe
This week, Dawson and his colleagues presented another updated version of this map. This time it includes objects located at a distance of 11 billion light-years from Earth. Over the past four years, astronomers have included twice as many galaxies in this survey. Thanks to this, measurements of cosmological parameters, including the rate of expansion of the Universe, which scientists make based on these data, have become much more accurate.
In particular, this data clearly suggests that dark energy exists and that it does cause space-time to expand faster and faster. Similarly, the eBOSS data indicates that neutrinos have mass, although small, and also confirm measurements of the rate of expansion of the Universe, which was obtained by the WMAP and Planck telescopes when observing another form of "echo" of the Big Bang – the microwave background radiation of the Universe.
As Dawson and his colleagues point out, this discovery has become particularly important for cosmology, since scientists now have much less reason to believe that serious discrepancies in the current and original rate of expansion of the Universe arose from errors in measurements made by WMAP and Planck on the one hand, and Hubble on the other.
Subsequent observations and closing the remaining "white spots" on this three-dimensional map of the Universe, scientists hope, will help them make measurements of the speed of expansion of the universe even more accurate. This discovery will not only bring humanity closer to understanding the nature of dark energy, but also allow cosmologists to understand why the universe is now expanding unexpectedly fast, and to uncover the physical phenomena that are responsible for this accelerated growth.