Dark energy: mysterious cosmic force appears to be weakening, say scientists

Long exposure shows trails of stars above Kitt Peak National Observatory, where astronomers are studying the nature of dark energy. Photograph: AP

Dark energy, the mysterious force powering the expansion of the universe, appears to be weakening, according to a survey that could “overthrow” scientists’ current understanding of the fate of the cosmos.

If confirmed, the results from the dark energy spectroscopic instrument (Desi) team at the Kitt Peak National Observatory in Arizona would have profound implications for theories about the evolution of the universe, opening up the possibility that its current expansion could eventually go into reverse in a “big crunch”.