The ultimate recoil of a black hole: what is the maximum high-energy impact impact?

Recent studies show that cosmic black holes can diffuse at incredible velocities approaching 10% of the speed of light. This is a very important discovery in the field of astrophysics and opens up new possibilities for understanding the dynamics of black holes and their collisions. Illustration of a black hole. Image: livescience.com This study, conducted by James Healy and Carlos O. Roost of the Rochester Institute of Technology, shows that the convergence of two black holes does not necessarily result in the formation of a stationary binary star system. A collision could cause a recoil, causing the newly formed black hole to travel along a new trajectory with sufficient speed. This effect is due to uneven distribution of gravitational energy during the collision, possibly due to uneven mass or pre-merging spin of the black holes. The most interesting thing is what kind of kinetic energy a newly formed black hole acquires. Scientists say the new object accelerates to about 28,562 kilometers per second, or more than 100 million kilometers per hour, after two black holes collide at high energies. The new discovery of black hole motion at such high speeds surpasses previous theories and calculations. So far, the maximum speed of these objects was assumed to be 5000 km/s.

Healy and Roast used a supercomputer to run 1381 full numerical simulations of the collision between two equally massive black holes with opposite spins along their orbital planes. This is how they determined the maximum speed of a black hole in space. How fast is a lightning-fast black hole? For comparison: To escape the Milky Way’s gravitational influence, you need to reach a speed of 497 km/s. The fastest man-made object is the Parker Solar Probe, which will reach a top speed of 400,000 miles in 2021. Initial configuration of double collision of black holes. Illustrated by Healy & Lousto, Physics. Rev. Lett., 2023 So a black hole accelerated to its maximum speed is surprisingly fast. Luckily, these are only theoretical calculations and in practice such speeds are very unlikely. However, the discovery of extreme limits will define the framework for future research. So far, he has found only one fast-moving black hole, which scientists say is the product of such a collision. It moves at a speed of about 1542km/s. At the end of the study, the scientists conclude that knowledge of the dynamics of black holes is of great importance for understanding the universe. They hope that further research will reveal more secrets about these mysterious space objects. Last time we talked about what black holes are and how they form.

source: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.071401