Black hole 'traffic jams' are forcing cosmic monsters to collide, new study finds

And you thought rush hour was bad on Earth! New research suggests some "cosmic intersections" have failed "traffic lights" that deem black hole collisions almost inevitable. 

At the hearts of all large galaxies lie cosmic monsters called supermassive black holes, enormous voids that swirl around everything in the galaxies themselves. This swirly behavior influences things like the disks of matter the galactic titan feasts on, stars and their systems — and, fascinatingly, even other black holes, albeit smaller, stellar mass ones.

It would also appear that such behavior around supermassive black holes can cause cosmic "traffic jams," and that these jams could actually be integral in slowing down the orbits of stellar-mass black holes. And, no longer zipping around, the affected black holes can be forced to collide, merge and create a larger daughter black hole.

Then, thanks to the immense gravitational iNFLuence of the traffic-jam-culprit supermassive black hole, a beast that can boast a mass millions (even billions) of times that of the sun, this process repeats. That results in even more black-hole collisions that create larger and larger stellar-mass black holes over time, with masses between three and a few hundred solar masses. 

Zooming out, all of this means the environment around a supermassive black holes is perfect for facilitating the growth of other black holes.

Related: Supermassive black hole at the heart of the Milky Way is approaching the cosmic speed limit, dragging space-time along with it

Some supermassive black holes are surrounded by a disk of gas and dust called an accretion disk; it is this disk which gradually feeds the black hole. The gravity of supermassive black holes generates powerful tidal forces in those accretion disks that cause them to glow brightly, creating a region called an Active Galactic Nucleus (AGN).