UBC Physicists recently proposed fluctuating space-time in a theory for dark energy that unifies general relativity and quantum mechanics. PhD students Qingdi Wang and Zhen Zhu along with professor Bill Unruh published their research in Physical Review D last week. You can also find out more by listening to an interview with Jaymie Matthews that aired on CBC Vancouver’s The Early Edition:
The work suggests that, at very small scales, the universe is constantly fluctuating between expansion and contraction. The fluctuations almost cancel each other but a small net effect is responsible for the “dark energy” that is causing the universe to expand at an accelerating rate.
Previous models of dark energy using quantum mechanics and relativity were not compatible. Models using quantum mechanics theorized that dark energy must be incredibly dense, but relativity predicted that the universe would explode with such dense dark energy. This new research resolves the incompatibility between the two models.