Quantum theory beats diffraction limit

The quantum-mechanical process that Einstein described as 'spooky action at a distance' could lead to new generations of smaller and faster computer chips. Normally the size of silicon chips is fixed by the so-called 'diffraction limit' - transistors and other features patterned by light cannot have dimensions smaller than half a wavelength. But now researchers at the Jet Propulsion Laboratory in the US and the University of Wales in Bangor have shown how 'entangled' photons could map out features that are many times smaller than the diffraction limit (Agedi Boto et al 2000 Phys. Rev. Lett. 85 2733).