Science. – New Evidence for the Nature of Matter in the Ancient Universe – Publimetro México

Madrid, 5 (Europe Press)

While the generally accepted model of structure formation relies on non-relativistic matter interacting only through gravity, i.e. “cold” dark matter, the alternative possibilities advocated by the standard scenario small-problem solution are based on the hypothesis that dark matter is made of warm particles that have A small, negligible thermal velocity, which is the “warm” dark matter.

“We have found that the recent JWST detections of galaxies in the first part of a billion years after the Big Bang are valuable evidence of the nature of matter,” says Dr. Umberto Maio, a researcher at the Italian National Institute of Astrophysics (INAF). at the Trieste Astronomical Observatory, and lead author of the paper describing the discovery just published in Astronomy & Astrophysics.

The research shows that dark matter, the main constituent of matter in the universe, consists of slightly “cold” or “warm” particles with a mass greater than 2 keV. Dark matter models with particle masses equal to or lighter than this limit were excluded from the study.

While previous work excluded the possibility of distinguishing the nature of matter using data from more recent epochs, data from much older epochs and dedicated numerical simulations—the basis of the new study—were needed to provide insight into the statistical trends of proto-epochs. Galaxies are breaking down the decay of paradigms.

“What we’ve done is apply our new complex numerical application of early galaxy formation to interpret the most recent JWST data,” says Dr. Maio. “We’ve seen that during the period when the first stars and galaxies are forming, the visible properties of structures in the universe depend on the mass of dark matter particles.”

Indeed, the study found evidence that the amount of cosmic star formation, ultraviolet luminosity, and molecular abundance differ in different models of dark matter, and these differences can be compared with the latest data from the JWST, the first to hit the universe. ” Ancient”.

“The study was based on the exceptional observations of galaxies in the first 500 million years discovered by JWST and published as early as late 2022,” says Professor Matteo Fell of the International School for Advanced Studies in Trieste and co-author of the research. .

“This is an important application of scientific data at such primordial times to constrain the nature of dark matter. Thanks to JWST, we have observed the most distant galaxies in the universe, and their properties are providing us with clear insights into what they are made of.”