In an advance that sounds like something right out of science fiction, Ulf Leonhardt and Thomas Philbin of the University of St Andrews have determined that a perfect lens (something not created yet but technologically plausible) could reverse the normally attractive Casimir force, making it repulsive. The Casimir force is a non-classical physical effect whereby two neutral plates placed in close proximity slightly attract. The Casimir force is especially relevant to micromachines and nanomachines, where the effect is more pronounced. If it could be reversed, this would solve many of the stickiness problems associated with tiny machines.

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