Researchers Observe Magnus Effect in Light for First Time

The Magnus effect can be observed in a wide range of systems. It describes, for example, the sideways force a spinning ball feels as it travels through the air, which explains why a baseball pitcher’s curveball curves, and why a badly hit golf ball slices. Light waves, which are made up of massless particles called photons, have their own version of spin. Light’s spin depends on whether its polarization, or direction of wave vibration, rotates in one direction or in the opposite direction as it travels. The Magnus effect for light (also called the spin Hall effect) causes the light to deflect due to the interaction between the light’s spin and shape of the light’s trajectory.