Quantum Camera Catches Ghostly Images

This eerie photo was taken with a quantum camera. It's being referred to as ghost imaging, but it's not really about ghosts in the sense of souls of the dead. 

This is about a sexy thing called quantum entanglement. Quantum physics has shown that two particles that are not even in each other's presence can react to what the other particle is doing. You know that phenomena people talk about in twins who may be states away from each other and tell when the other one is feeling sick? Put easily, imagine the Borg and the "Collective."

In the case of the quantum camera, Quantum cameras capture ghost images by making use of two separate laser beams that have their photons entangled. Only one beam encounters the object pictured, but the image can nevertheless be generated when either beam strikes the camera...For the experiment, researchers passed a beam of light through etched stencils and into cutouts of tiny cats and a trident that were about 0.12 inches tall. A second beam of light, at a different wavelength from the first beam but nevertheless entangled with it, traveled on a separate line and never hit the objects. Amazingly, the second beam of light revealed pictures of the objects when a camera was focused on it, even though this beam never encountered the objects.

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