
Quantum Camera Capable of Snapping Photos of 'Ghosts' - KerryJones
http://www.mnn.com/green-tech/research-innovations/stories/new-quantum-camera-capable-of-snapping-photos-of-ghosts
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gus_massa
The National Geographic article (linked in the article) has much more
information and makes this intelligible:
[http://news.nationalgeographic.com/news/2014/08/140827-quant...](http://news.nationalgeographic.com/news/2014/08/140827-quantum-
imaging-cats-undetected-photon-science/)

> _In the new experiment, the physicists entangled photons in two separate
> laser beams with different wavelengths, and hence color: one yellow and one
> red._

> _The team passed the red light beam through etched stencils and into cutouts
> of tiny cats and a trident [...]. The yellow beam traveled on a separate
> line, never hitting the objects. [...]_

> _After the red light passed by the objects, the physicists ran it together
> with the yellow laser beam at both parallel and right angles._

> _The red light was then discarded, and the yellow light headed for a camera.
> There, that yellow light revealed a picture of the object. And a negative of
> the picture emerged from the light that had interfered at a right angle._

This is a very important detail. After the red light hits the target, it
interacts with the yellow light. So it's not unbelievable that the yellow
light may form some kind of image.

In the mnn article, it looks like the red and yellow laser never meet again,
so the information about the target is transmitted in some spooky way.

~~~
KerryJones
Good point, thanks for that

