Analysis of exploding stars suggests dark energy varies over time

An analysis of 2,884 exploding white dwarf stars has revealed new evidence that dark energy may change over time, ScienceDaily Physics, Science Daily, and Around Prague all reported. Dark energy is the force responsible for the accelerating expansion of the universe. The new findings challenge a central assumption of modern cosmology, which traditionally treats dark energy as a constant value across space and time. [1][2][3]

The dataset represents the largest collection of exploding white dwarf stars ever compiled for a single cosmic study, ScienceDaily Physics reported. Astronomers use these standard light sources to measure vast cosmological distances and track how the cosmic expansion rate changes across billions of years. By expanding the statistical sample to nearly 3,000 objects, the researchers achieved the precision required to detect subtle variations in the behaviour of dark energy over time. [1]

Standard relativistic cosmology describes an expanding universe that originated approximately 13.8 billion years ago following an epoch of rapid cosmic inflation. Current models place the comoving diameter of the observable universe at about 93 billion light-years. Cosmologists typically model this evolution using the cosmic microwave background and a constant dark energy density, but evidence of time-varying dark energy could require revisions to the standard cosmological framework. [5][6]

If confirmed by future observational datasets, a time-varying dark energy force would alter predictions regarding the long-term history and final fate of the universe, ScienceDaily Physics reported. Researchers expect that larger surveys will further test these measurement precision limits. [1]