On the hunt for ‘hierarchical’ black holes

Black holes, detected by their gravitational wave signal as they collide with other black holes, could be the product of much earlier parent collisions. Such an event has only been hinted at so far, but scientists believe we are getting close to tracking down the first of these so-called 'hierarchical' black holes.

from Latest Science News -- ScienceDaily https://ift.tt/3l0gUzN