Dark Energy is not what we are shaking – and it can transform the cosmos

Dark Energy is one of the most mysterious features of our universe – we know it knows what it is, but it controls how the universe is expanding, as well as its ultimate fate. Now a study of millions of heavenly objects has revealed that we may have thought about it all wrong, with potentially dramatic consequences for the cosmos.

“This is the biggest tip we have about the nature of dark energy in the approximately 25 Barlind since we discovered it,” says Adam Riess at Johns Hopkins University in Maryland.

The result comes from three years value of data collected by Dark Energy Spectroscopic Instrument (DESI) in Arizona. By combining this data with other measurements, such as maps of the cosmic microwave background radiation and supernovae, Desi-Team has concluded that dark energy may have changed over time direction that contradicts the standard of cosmology, called Lambda CDM.

“This is the forefront of human knowledge,” says Desi team member will Percival at the University of Waterloo in Canada. “We see something amazing with the whole universe.”

DESI is mounted on a telescope and works by measuring the “red shift” of light emitted by distant galaxies or how the wavelengths of that light are started as it moves through the universe. From this, scientists can determine how much the universe has expanded the day of light and calculator how this expansion changes. So far, the team has analyzed light from nearly 15 million galaxies and other bright objects in the sky.

For decades, physicists agree that the universe is expanding with a fixed acceleration speed, a cosmologically constant known as Lambda, which has been interpreted as pushing of dark energy. But in April 2024, Desi’s measurements showed the first tips that the universe can actually accelerate less quickly over time – making the cosmological constantly not so constant.

Riess, who is not at the DESI team, says he was sure at that time he would find would continue with more data. In fact, it has only become stronger. “It’s very exciting for me that it seems [the team] Found no problem in the analysis after another year and after adding more data. If something, the result is meaningful, ”he says.

That said, finding still does not meet the statistical level “5 Sigma” that physicists conventionally use to mark a discovery as real, rather than a statistical fluke. The current analysis reaches a maximum of 4.2 Sigma, but team member Mustapha Ishak-Boushaki at the University of Texas in Dallas says the team believes that the result when DESI continues to take data must be reached 5 Sigma within two years. “This result about dark energy is something that we did not happen in our lifetime,” he says.

An insurance, says Ishak-Boushaki, is that the finding is not only dependent on data from DESI, but also on several other studies of the universe. Riess compares the situation with a multi-legged stool where breaking a leg or removing a data set-do does not make the conclusion fully crumbles.

Assuming the legs holding, the universe could look very different from our current picture of it. If Dark Energy continues to become weaker, the universe can reach a condition where it is expanded at a constant speed Instratead with faster and faster, says Ishak-Boushaki. Some dramatic scenarios also become more plausible, such as “Big Crunch”, where Cosmos begins to contract and instructs to expand and eleutally collapse in themselves, he says.

The exact future of the universe remains an open question, and DESI is the only tool that scientists use to answer it. Riess points to several other studies of the universe, such as NASA’s Nancy Grace Roman Space Telescope and Vera Rubin Observatory in Chile, designed to help shed light on the true nature of dark energy.

While mathematical models for a universe of changing dark energy still need to catch up on these observations, Percival says he expects future theoretical work to help design even more experiment that will directly test our dismounting about this mysterious power.

“As far as theoretical models opened Pandora’s box straight. We were stuck with a cosmologically constant,” says Ishak-Boushaki. “We are no longer stuck.”