Twisting a strip of paper and joining the ends forms a model for the Möbius strip, a surface with one continuous side. This popular party trick for mathematicians has recently developed a new dimension: physicists have manipulated light to form a Möbius shape.
This amazing result is dependent on a property of light called polarisation, which describes the movement of light’s electric field. By focusing a laser beam through a liquid crystal lens, the light achieves a specific polarisation. Using two such polarised beams and a gold bead smaller than its wavelength, scientists created interference which exhibited the twists characteristic of a Möbius strip.
The practical applications are not immediately clear but it will no doubt spark great discoveries in the future. Mathematicians might like to investigate the geometrical properties of the Möbius strip further, while Physicists might be fascinated by the way in which the discovery elucidates the interaction between light and matter.