Dark matter and universe's expansion: Unraveling cosmic secrets

A mysterious force, which expands the universe but does not emit or reflect electromagnetic radiation, dark matter fascinates researchers who are constantly working to learn more about it. However, we still don't know much about it. It turns out that previous theories might be incorrect. The latest analyses by the research team suggest that dark energy could have changed over time, and this discovery challenges the standard lambda-CDM cosmological model.

DESI is installed on a telescope in Arizona and measures the redshift of light from distant galaxies. Thanks to this, scientists can track how the universe is expanding. Analysis of light from nearly 15 million galaxies indicates that the universe may be accelerating more slowly than previously thought.

For many years, physicists agreed that the universe was expanding at a specific acceleration rate, known as the cosmological constant lambda, which is interpreted as the effect of dark energy. However, in April 2024, measurements conducted by DESI suggested that the universe might be accelerating at a slower pace, which questions the constancy of this cosmological constant.

Researchers suspect that dark matter may be weakening, and if that is indeed the case, the universe might potentially slow down its expansion. Scientists are pondering what constant expansion could mean for the universe, and are developing various potential scenarios in which they speculate about a big crunch and the process of space contraction.

Although the current results have not yet reached the 5 sigma level necessary to confirm a discovery, the DESI team is confident that future data could change this. Research on dark energy plays a crucial role in understanding the future of the universe and may lead to groundbreaking changes in cosmology. DESI research supports other projects like the Nancy Grace Roman Telescope and the Vera Rubin Observatory.