His name is Marcus: he is four and a half and possesses that deep gravity and seriousness that only small children and mountain gorillas have ever been able to master.

The difficulty lay with the mind accommodating itself to the notion of the plane, with all its weight, defying gravity, staying aloft. She understood the aerodynamics of flight, could comprehend the laws of physics that made flight possible, but her heart, at the moment, would have none of it. Her heart knew the plane could fall out of the sky.

The gravitational waves of the first detection were generated by a collision of black holes in a galaxy 1.3 billion light-years away, and at a time when Earth was teeming with simple, single-celled organisms. While the ripple moved through space in all directions, Earth would, after another 800 million years, evolve complex life, including flowers and dinosaurs and flying creatures, as well as a branch of vertebrates called mammals. Among the mammals, a sub-branch would evolve frontal lobes and complex thought to accompany them. We call them primates. A single branch of these primates would develop a genetic mutation that allowed speech, and that branch— Homo Sapiens— would invent agriculture and civilization and philosophy and art and science. All in the last ten thousand years. Ultimately, one of its twentieth-century scientists would invent relativity out of his head, and predict the existence of gravitational waves. A century later, technology capable of seeing these waves would finally catch up with the prediction, just days before that gravity wave, which had been traveling for 1.3 billion years, washed over Earth and was detected.Yes, Einstein was a badass.

I would feel infinitely more comfortable in your presence if you would agree to treat gravity as a law, rather than one of a number of suggested options.

Gravity is a contributing factor in nearly 73 percent of all accidents involving falling objects.

If you blame gravity for falling in love, even God has the right to laugh at you.