Lecture, Barnard's Inn Hall, Tuesday, 3 Mar 2026 - 18:00

The Shape of Gravity: Why On Earth Are Planets Spherical?

Abstract image featuring translucent, glowing bubbles in shades of pink and blue, suspended around a thin diagonal line against a dark background

We often take for granted that planets, shaped by the force of gravity, are spherical. However, a closer look reveals that the Earth is not a perfect sphere—it is slightly squashed. But is it squashed like a pumpkin or more like a peanut? And is the sphere truly the only possible shape for a planet? As planets grow larger and must sustain increasingly extreme forces, can we still assume they maintain a spherical shape? These seemingly simple questions have fascinated scientists and mathematicians since the time of Newton, giving rise to profound mathematical theories that deepen our understanding of the universe.

Professor Alain Goriely

Professor Alain Goriely FRS

Gresham Professor of Geometry

Alain Goriely is a mathematician with broad interests in mathematical methods, mechanics, sciences, and engineering. He is well known for his contributions to dynamical systems...

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