Astrophysicists have found characteristic density fluctuations in the distribution of quasars located at redshifts from 0.8 to 2.2. These important fluctuations, called the Sakharov oscillations, have been detected for the first time at such distances and confirm the standard cosmological model. Results article published in Monthly Notices of the Royal Astronomical Society.
There are three main sources of cosmological information - relic radiation, type Ia supernovae, and Sakharov oscillations (CO). A joint analysis of these sources makes it possible to determine the main parameters of the Universe, such as the density of dark matter and dark energy, with an accuracy of several percent. Sakharov oscillations represent density fluctuations of ordinary matter with a fixed size at a given cosmological epoch. The wavelength of the Sakharov oscillations, observed in the correlation distribution functions of various objects (for example, galaxies), provides information about the history and composition of the Universe.
“In this paper, Sakharov's oscillations were first discovered in the distribution of 147,000 quasars in the extended eBOSS survey. Prior to this, COs were detected in the distribution of galaxies at small redshifts (<1) and in the distribution of Lyα-clouds at redshifts ~ 2.5, thus the important window of redshifts was “closed”, - one of the co-authors explained for Indicator. Ru the essence of the work Mikhail Ivanov from the Institute for Nuclear Research RAS. "Using only CO measurements in these three redshift ranges, it was possible to detect the accelerated expansion of the Universe at the 6.6 sigma level, which confirms the validity of the cosmological ΛCDM model."
Currently, astronomers are still collecting data. It can be expected that the data volume of the final sample of eBOSS quasars will exceed the volume of all current SDSS data by three times. These data will be used to elucidate the nature of dark energy, the dynamics of the early Universe, and determine the neutrino masses.