A new analysis of a catalog containing nearly 3,000 white dwarfs that exploded as type Ia supernovas suggests that dark energy—the mysterious force driving the universe’s accelerated expansion—is evolving over time. The findings align with previous results from the Dark Energy Spectroscopic Instrument (DESI) released in 2024, which also indicated that dark energy’s influence is weakening rather than remaining constant.
This research provides what researchers describe as the most detailed picture to date regarding the evolution of the universe and the role of dark energy. “We’ve rebuilt 3 decades of astronomical observations into a single, consistent framework,” said Ryan Camilleri of the University of Queensland. He noted that the team integrated their data with other cosmic measurements, including relic radiation from the Big Bang and maps of galactic distribution. “Instead of confirming the standard model of cosmology, which assumes dark energy is fixed and unchanging, we have more evidence that dark energy may change over time,” Camilleri added.
Type Ia supernovas occur when a white dwarf, the remnant core of a star roughly the mass of our sun, accumulates enough matter from a companion star to exceed the Chandrasekhar limit. These explosions are considered “standard candles” because their light output is remarkably uniform, allowing astronomers to measure cosmic distances by analyzing the redshift of their light.
The study accounts for various factors that can affect light observation, such as cosmic dust, galaxy mass, and gravitational lensing. Davis, another researcher involved in the study, highlighted that while early DES data in 2024 hinted at time-varying dark energy, the new compilation shows a deviation from the standard model in a slightly different direction. Similarly, DESI surveys of relic sound waves from the early universe found hints of variation.
According to Davis, these independent measurements challenge the long-held assumption that dark energy is static. Beyond clarifying the nature of dark energy, the research could offer insights into reconciling quantum physics and general relativity—two highly successful but currently incompatible theories of the universe. The team expects further data from the Dark Energy Bedrock All-Sky Supernova program (DEBASS), which is detecting hundreds of additional local supernovas, to bolster these findings.
The complete results are available on the arXiv repository.
Skeptical until DEBASS confirms this independently. We’ve had false alarms about varying constants before.
Wait, does this mean the universe will eventually stop accelerating? I need more details on what happens next.
Three decades of data finally lining up with new observations? My confidence in standard cosmology just took a major hit.
This is huge if it holds up. A changing dark energy could solve the greatest unsolved problem in physics forever.