How will the universe end? A changing understanding of dark energy may provide a new answer

Scientists are homing in on the nature of a mysterious force called dark energy, and nothing short of the fate of the universe hangs in the balance. Dark energy makes up nearly 70% of the universe and scientists are getting a little closer to understanding how it behaves. The big question is whether dark energy is a constant force, or whether it may be weakening. Results posted Wednesday bolster the case that the force is weakening, though scientists are not yet certain and they still haven’t worked out what this means for the rest of their understanding of the universe.