Dark energy may not be constant – this discovery could undermine our entire model of cosmological history
03/04/2025
Licia Verde et al.
|
ICREA Profesor of Cosmology at ICCUB of the Universitat de Barcelona
Licia Verde et al.
ICREA Profesor of Cosmology at ICCUB of the Universitat de Barcelona
The great Russian physicist and Nobel laureate Lev Landau once remarked that “cosmologists are often in error, but never in doubt”. In studying the history of the universe itself, there is always a chance that we have got it all wrong, but we never let this stand in the way of our inquiries.
A few days ago, a new press release announced groundbreaking findings from the Dark Energy Spectroscopy Instrument (DESI), which is installed on the Mayall Telescope in Arizona. This vast survey, containing the positions of 15 million galaxies, constitutes the largest three-dimensional mapping of the universe to date. For context, the light from the most remote galaxies recorded in the DESI catalogue was emitted 11 billion years ago, when the universe was about a fifth of its current age.
DESI researchers studied a feature in the distribution of galaxies that astronomers call “baryon acoustic oscillations”. By comparing it to observations of the very early universe and supernovae, they have been able to suggest that dark energy – the mysterious force propelling our universe’s expansion – is not constant throughout the history of the universe.
An optimistic take on the situation is that sooner or later the nature of dark matter and dark energy will be discovered. The first glimpses of DESI’s results offer at least a small sliver of hope of achieving this.
This article was originally published in The Conversation.
DESI researchers studied a feature in the distribution of galaxies that astronomers call “baryon acoustic oscillations”. By comparing it to observations of the very early universe and supernovae, they have been able to suggest that dark energy – the mysterious force propelling our universe’s expansion – is not constant throughout the history of the universe.
An optimistic take on the situation is that sooner or later the nature of dark matter and dark energy will be discovered. The first glimpses of DESI’s results offer at least a small sliver of hope of achieving this.
This article was originally published in The Conversation.