Kerr ellipticity refers to the distortion of a black hole's event horizon from a perfect sphere to an oblate spheroid due to the black hole's rotation. This phenomenon is a direct consequence of the Kerr metric, which describes the geometry of spacetime around a rotating black hole, highlighting the intricate relationship between mass, rotation, and spacetime curvature.

Kerr Ellipticity

Distortion of a black hole's event horizon

Perfect sphere

An oblate spheroid is a three-dimensional shape formed by rotating an ellipse about its minor axis, resulting in a flattened sphere. This shape is significant in astronomy and geophysics as it closely approximates the shape of planets like Earth due to their rotation-induced equatorial bulge.

Oblate Spheroid

Black hole's rotation

The Kerr metric describes the geometry of spacetime around a rotating massive object, providing a solution to the Einstein field equations of general relativity. It extends the Schwarzschild metric by incorporating angular momentum, allowing for the study of phenomena such as frame dragging and the ergosphere in rotating black holes.

Kerr Metric

Geometry of spacetime

Rotating black hole

Relationship between mass and rotation

Spacetime curvature is a fundamental concept in Einstein's General Theory of Relativity, describing how matter and energy influence the geometry of the universe. It explains gravity not as a force, but as a result of objects following the curved paths in spacetime created by mass and energy distributions.

Concepts

Your Lessons