Light Bends

Every physics student knows that light travels in a straight line. But now researchers have shown that light can also travel in a curve, without any external influence. The effect is actually an optical illusion, although the researchers say it could have practical uses such as moving objects with light from afar.

It's well known that light bends. When light rays pass from air into water, for instance, they take a sharp turn; that's why a stick dipped in a pond appears to tilt toward the surface. Out in space, light rays passing near very massive objects such as stars are seen to travel in curves. In each instance, light-bending has an external cause: For water, it is a change in an optical property called the refractive index, and for stars, it is the warping nature of gravity.