plans to build two relatively small devices that act as 'holographic interferometers' to measure the shaking or vibration in split beams of light traveling through a vacuum. If the team finds the shaking in their measurements and records them, the theory of a holographic universe will have some evidence of non-smoothness in space-time and perhaps a foothold in bringing light to the heavily debated theoretical physics." A BALL spinning in a vacuum should never slow down, since no outside forces are acting on it. At least that's what Newton would have said. But what if the vacuum itself creates a type of friction that puts the brakes on spinning objects? The effect, which might soon be detectable, could act on interstellar dust grains. In quantum mechanics, the uncertainty principle says we can never be sure that an apparent vacuum is truly empty. Instead, space is fizzing with photons that are constantly popping into and out of existence before they can be measured directly. Even though they appear only fleetingly, these "virtual" photons exert the same electromagnetic forces on the objects they encounter as normal photons do. Now, Alejandro Manjavacas and F. Javier Garca de Abajo of the Institute of Optics at the Spanish National Research Council in Madrid say these forces should slow down spinning objects. Just as a head-on collision packs a bigger punch than a tap between two cars one behind the other, a virtual photon hitting an object in the direction opposite to its spin collides with