Gravity

acroyear70 made a post today about gravity as a weak force.

I'm waiting for "them" to discover that gravity is not a weak force, but a pair of opposing forces, one attractive and one repulsive. The net result on "normal" matter is slightly attractive, but the result on "dark" matter is slightly repulsive -- thus the universe (being mostly dark matter) continues to expand, and at an increasing rate.

Maybe there is a sci-fi novel in that idea somewhere. Activate the dark-matter gravimetric drive!