Self-propelled Pair of Black Holes ⚡ экспресс
Two massive black holes, whirling around, scatter lightweight stars like a sling throws stones, causing their orbit to shrink. But a new analysis shows that throwing "stones" also pushes the pair itself — its center of mass slides in a spiral, like a boat propelled by hurled stones. For merging black holes in galactic centers, this self-acceleration could carry them far from the center. Where will such a "motor" lead them?
Two black holes, orbiting each other, behave like a boat rowing with stars. Each passing star is flung away, like a stroke of an oar, and transfers momentum to the pair. For a long time, it was thought this simply brings the black holes closer. But new analysis has shown: by flinging stars unevenly, the system pushes itself sideways, spins, and tilts the orbit.
The reason is the shape of their path. The orbit is asymmetric, so the strokes are of different strength. The black holes begin to 'swim' away from the center of the galaxy, moving thousands of light-years away. This explains why supermassive black holes are sometimes found not at the center, and also changes their gravitational waves as they approach.
The most unexpected result: instead of damping, the orbit becomes increasingly elongated, like a lopsided oval. A similar orbital precession is seen in Mercury — explained by Albert Einstein — but here, instead of curved space, stellar 'oars' are at work.
🎯 A pair of black holes moves by flinging stars, like a boat rowing with oars.