There is something strange in the universe. Something that challenges our most consolidated cosmological theories and could force us to rethink everything we thought we knew about the cosmos. This is dark energy, the mysterious force that drives the accelerated expansion of the universe. Until now, we thought it was an immutable constant. But a surprising new discovery suggests it could evolve over time.
A revelation which, if confirmed, would be a real earthquake in the world of cosmology. Do you want to know more about this cosmic enigma? I tried to put the information in order a bit. If you want, start from here and then delve deeper: everything begins, as in every journey, with an absolutely special "geographical map".
An unprecedented 3D map
At the center of this potential breakthrough is a new 3D map of the universe, the largest ever made. It is based on data collected during the first year of observations of Dark Energy Spectroscopic Instrument (DESI), an instrument contained in the Nicholas U. Mayall telescope located in Arizona.
What does this map track? But nothing, just the expansion of the universe over the last 11 billion years. I link the study here.
DESI is an extraordinary experiment that produces astonishing data.
Adam Riess, the Johns Hopkins University astrophysicist who led the team that discovered dark energy 25 years ago.
Thanks to 5.000 tiny robots collecting data at an unprecedented rate, DESI is able to observe 5.000 galaxies every 20 minutes. We go to sleep, and when we get up to brush our teeth he has observed 100.000 galaxies. Nightly.
Does dark energy evolve and vary over time?
What makes the DESI data really interesting are the subtle clues that suggest a possible evolution of dark energy over time. By analyzing the distribution of galaxies and using supernova explosions as distance indicators, the researchers obtained results that do not fit the standard cosmological model, in which dark energy is considered a constant.
The properties of dark energy would not actually correspond to a simple cosmological constant, but could have some deviations.
Nathalie Palanque-Delabrouille, an astrophysicist at Berkeley Lab and a collaborator on the DESI project.
If confirmed, this discovery would have enormous implications for our understanding of the cosmos.
What's more: it would completely overturn cosmology.
Experts between enthusiasm and caution
It must be said: the researchers themselves obviously warn against drawing hasty conclusions. Although the preliminary results have only a 400 in XNUMX chance of being a statistical anomaly, well above the typical threshold for a scientific discovery, is still “weak” as evidence.
In any case, the possibility that dark energy is variable has sparked great excitement in the physics community. “It's an adrenaline shot for the entire cosmological community,” he says Daniel Scolnic, physicist at Duke University.
Dark energy, towards a new understanding of the cosmos
If these first results are confirmed by further data, as mentioned, we are facing a revolution in our understanding of the universe. Dark energy evolving over time would imply new and unknown physics, opening the door to radically different theories and models.
The next few years will be crucial to verify this discovery and explore its implications. As new data arrives from DESI and other experiments, cosmologists will have the opportunity to unlock the secrets of dark energy and perhaps rewrite the history of the cosmos.
