Studying the past and future of the universe using statistical methods to measure distances

New research has improved the accuracy of the parameters that govern the expansion of the universe. More precise parameters will help astronomers determine how the universe has evolved to its present state and how it will evolve in the future.

It is well established that the universe is expanding. But without a datum in space, it’s difficult to accurately measure the expansion rate of space. Therefore, astronomers are looking for reliable landmarks.In the same way that a candle dims as it recedes, even if the candle itself remains unchanged, distant objects in the universe appear to dim.

If we know the intrinsic (initial) luminosity of an object, we can calculate its distance based on its observed luminosity. Objects of known luminosity in the universe that allow us to calculate distances are known as “standard candles”.

An international team led by Maria Giovanna Dainotti, assistant professor at the National Astronomical Observatory of Japan (NAOJ) and Giada Bargiacchi, PhD student at the Scuola Superiore Meridionale in Naples, with the help of NAOJ’s supercomputing facility takes the lead. by Kazunari Iwasaki, assistant professor at NAOJ and member of the Center for Computational Astrophysics, has opened up a new area of ​​research by leveraging the use of a variety of new statistical methods.

New research has improved the accuracy of the parameters governing the

They analyzed data from a variety of standard candles such as supernovas, quasars (extremely powerful black holes that consume matter in the distant universe) and gamma-ray bursts (strong rays of suddenly). Different standard candles are useful at different distances, so combining multiple standard candles allows the team to map larger areas of the universe.Their work has been published in two articles in the Astrophysical Journal.

Provided by National Astronomical Observatory of Japan