Entangled photons create images of things they never interacted with

Science : A quirk of quantum entanglement allowed researchers to create images of target objects using photons that never interacted with the object. Using the technique, Anton Zeilinger of the Austrian Academy of Sciences in Vienna and his colleagues created images of cats that had been cut out of thin slices of silicon. The process starts with two pairs of entangled photons. One of the photons in the first pair is sent through the target object and one of the second pair is sent past it. They are then allowed to interfere with each other. The interference is passed to the second pair of entangled partners, which are sent to a camera to build an image of the target object. To ensure that the effect was real, Zeilinger’s group sent photons with wavelengths the camera couldn’t see toward the target and entangled them with photons that the camera could see. The result was two images showing either the outline of the object or showing the object directly, depending on whether the photon detected was entangled with the photon that went through or past the target.