Scientists tie light into a knot

 Like your shoelaces or electrical cords, light can get twisted into knots. Now, scientists have used a computer-controlled hologram and theoretical physics to turn a light beam into pretzel-like shapes.

The twisted feat not only led to some pretty cool images, but the results have implications for future laser devices, the researchers say.

"In a light beam, the flow of light through space is similar to water flowing in a river," said lead researcher Mark Dennis of the University of Bristol in England. Even though the light from something like a laser pointer travels in a straight line, it can also flow in whirls and eddies, Dennis explained.