Good God.

Ok... first steps towards x-ray vision?

x-ray vision already exists. Haven't you ever heard of super man?

Some people are so naive.

From what I can tell, that's not really a "quantum camera" in the way people are thinking of it. The photon detector is just telling the camera which photons hit the target and which missed, so it constructs a silhouette.

I think the big deal emon is that its not detecting the specific photons that hit the target, (like a traditional camera if I understand correctly) but instead constructing an image using photons that coorespond to the photons hitting the target. In effect it's taking a picture from around a corner.

So, Bets on how long untill this becomes used for perverts and the FBI?

so we have a way to see thorugh cloaking devices, without yet having invented cloaking devices...

oh sh*t, old predator didnt see that one coming.

if(getThingFlags(source) & 0x8){
  do her}
elseif(getThingFlags(source) & 0x4){
  do other babe}
else{
  do a dude}

firstly I really doubt this would see through any form of cloak, the camera still needs another device to say that a photon has hit the area of the object it is trying to photograph.

It then looks for corresponding photons in time that hit it from the same light source and gets information out of them through some form of interference correlation which I'm not all too sure how it works.

So I "suppose" if you knew something was stealthed and light was shinning on the object you *might* be able to "see" it with this camera, but it would all depend on what the cloak actually does with the light, whether it bends it around itself, ah feck knows what it could do tbh.

as for the whole idea of the two photon interference theory, well I'm having some trouble getting my head around how it even exists. I've only done single photon wave-particle duality so what I know about this pretty much zero.

what I'm trying to get my head around is how two seemingly separate photons can hold information about it each through interference, when in reality the "interference" (I say that loosely as I don't think this really is interference as I know it at least) itself can be across huge distances.

the way I think it *might* work is at the point in which the photon's are emitted from source. When the particle that drops down from a higher energized quantum state to lower state and gives off energy, in the form of an electromagnetic wave/particle you normally expect it to be in the form of just one wave/particle.

But thinking about it, I don't believe there is any reason why it couldn't give off 2 (or more) waves/particles of half (or less) energy. Assuming they are reasonably co-linear in there emission direction but still separated enough so that you can stop the path of one and let the other continue, one photon could hold information about the other and communicate it over (in theory) infinite distance.

Hence if one photon gets absorbed, it should in theory effect how the other behaves, what that exact effect might be I don't know, nor do I have a clue how you would go about detecting it, also importantly you'd have to detect it after the photon hitting the target had been absorbed or whatever.

[edit] just thinking about that last sentence a bit more. There has to be some form of "reference" to compare against when the photon changes as a result of the paired photon being absorbed etc...If there are some common effects you can see in the photon hitting the camera, such as the other photon being absorbed (or not) I guess you could make a black and white image pretty easy.[/edit]

still, interesting.