As the angular momentum is conserved, the black hole retains the original star's angular momentum.
As the original star's radius is only known approximately, the black hole's angular momentum can only be estimated.
The angular momentum is important in the Kerr metric to compute frame dragging.
As the angular momentum is conserved, the black hole retains the original star's angular momentum. As the original star's radius is only known approximately, the black hole's angular momentum can only be estimated. The angular momentum is important in the Kerr metric to compute frame dragging.