The nothing that is

Recent measurements... suggest that the universe as a whole has zero energy, zero charge, and zero angular momentum. How is this possible? All energy due to matter (which is positive) is canceled by an equal amount of gravitational energy (which is negative). There are equal amounts of positive and negative charge, and we cannot create one without creating the other. Zero angular momentum means that the universe has no net spin. The universe, then, is a whole lot of nothing: yin and yang that cancel each other out. Locally, in our own neighborhood, we seem to have lots of stuff: matter, charges, motion, entropy, and uncertainty. But globally, none of these exist, never have and never will.

-- from The Rise of the Uncertain by Vlatko Vedral at Nautilus