  We study the relation between quantum computational complexity and general
relativity. The quantum computational complexity is proposed to be quantified
by the shortest length of geodesic quantum curves. We examine the
complexity/volume duality in a geodesic causal ball in the framework of Fermi
normal coordinates and derive the full non-linear Einstein equation. Using
insights from the complexity/action duality, we argue that the accelerated
expansion of the universe could be driven by the quantum complexity and free
from coincidence and fine-tunning problems.
