What are the latest discoveries about black holes?
The most exciting things to me are the first supercomputer simulations of two black holes that spiral together and then collide, triggering wild vibrations of their warped space and time. There’s a fascinating recent simulation by a group led by Manuela Campanelli and Carlos Lousto, who are now at the Rochester Institute of Technology, in which the two holes are spinning with their axes pointed in opposite directions in the plane of their orbit. As they come together, the whirling space around each hole grabs hold of the other hole and throws it upward, just before they collide. The merged hole flies upward from where the collision occurred, vibrating wildly, and fires a burst of gravitational waves in the opposite direction in order to conserve total momentum. It’s similar to how a smoke ring propels itself forward through air.
