Black holes may split under extreme conditions

Physicists from the University of Naples Federico II and the University of Southern Denmark proposed in a study published in October 2026 in Physical Review D that a rapidly rotating black hole could, in theory, split into two. This idea challenges previous understanding, as thermodynamics usually prevents such a division due to the need for increasing entropy, a measure of disorder in the universe.

Splitting would change black hole shape

The study suggests that if such a split were to occur, the event horizon—the boundary beyond which nothing can escape a black hole’s gravity—would gradually deform. This deformation would create a shape resembling two legs detaching from a single waist. This unusual image inspired the study’s title, which focuses on black holes capable of adopting such a shape.

Splitting requires extreme conditions

For the split to occur, the black hole would need to be rotating at near-maximum speeds. Under these conditions, the energy balance shifts, making the split no longer formally prohibited by the laws of physics. However, the two resulting pieces would need to move apart rather than collapsing back on each other under their own gravity, a requirement that makes the process extremely challenging.

The phenomenon remains unobserved

The phenomenon remains purely theoretical and has not been observed in nature. The research highlights the possibility of black hole splitting only under extreme rotational conditions, where the constraints of thermodynamics are less restrictive. Scientists continue to study such theoretical scenarios to better understand the behavior of black holes in the universe.