Two experiments that use nonlinear crystals to control the spatial distribution of photons in optical images bring the field of quantum imaging closer to maturity. Quantum information processing could ultimately benefit. God, it seems, plays dice. Randomness lies at the root of many quantum effects: in the arrival times of the photons on a detector, for example; or, if the intensity is such that the photons cannot be distinguished individually, in the temporal fluctuations of the current generated in the detector by those photons. In the past two decades, physicists have found ways to tame this 'quantum noise', and to master, at least in some instances, the temporal distribution of photons.
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