A frog suspended in the void, without visible string: the scene looks like a magic trick. Andre Geim’s experience, however, is based on a very real physical property. A very intense magnetic field can exert sufficient force to balance the weight of the animal.
Water and other substances in living beings have a weak diamagnetic response. In the laboratory device, this response becomes important enough to produce levitation. A refrigerator magnet would obviously not reproduce the scene.
Geim and Michael Berry received an Ig Nobel Prize in 2000 for this work. Later, Geim shared the Nobel Prize in Physics for graphene. The frog was therefore neither a hoax nor evidence that gravity would have disappeared.
Geim said the frog was returned to the biology department. A weakly diamagnetic body had left its support in an exceptional device.
What we know
Diamagnetic levitation in the laboratory; no abolition of gravity or domestic magnet.
To go to the source
References accessed October 11, 2026. Linked pages may be in another language.
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