This invisible "frenemy" does not emit or reflect light but provides the gravitational glue that keeps galaxies from flying apart. It makes up roughly 85% of all matter.
Fourteen billion years ago, everything we’ve ever known—every star, planet, and person—was packed into a space smaller than the period at the end of this sentence. In an event known as the , this tiny, hot, and incredibly dense point began to rapidly expand. Astrophysics For People In A Hurry
One of the book's most profound takeaways is the . The same laws of physics that govern a falling apple on Earth also govern the rotation of distant galaxies and the behavior of light across the void. This invisible "frenemy" does not emit or reflect