Dr Rossana Ruggeri, from the QUT School of Chemistry and Physics who studies the properties of the universe on the largest scales, is part of the Dark Energy Spectroscopic Instrument or DESI, which is an international experiment with more than 900 researchers from over 70 institutions around the world, including QUT, Swinburne University and the University of Queensland, and is managed by the US Department of Energy’s Lawrence Berkeley National Laboratory.

DESI used millions of galaxies and quasars to build the largest 3D map of our universe to date. Combining its data with other experiments shows signs that the impact of dark energy may be weakening over time – and the standard model of how the universe works may need an update.

The fate of the universe hinges on the balance between matter and dark energy: the fundamental ingredient that drives its accelerating expansion.

Taken alone, DESI’s data is consistent with our standard model of the universe: Lambda Cold Dark Matter – where CDM is cold dark matter and lambda represents the simplest case of dark energy, where it acts as a cosmological constant. However, when paired with other measurements, there are mounting indications that the impact of dark energy may be weakening over time and other models may be a better fit.

Those other measurements include the light leftover from the dawn of the universe – the cosmic microwave background or CMB, supernovae, and how light from distant galaxies is warped by gravity – or weak lensing.