Entangled Definition and 268 Threads

Has it or can it be proven whether a "pair" of entangled photons are really the same photon (or not)? Thanks, FRQ

I asked this question over in the QM forum, but it fizzled out there. I think it's more appropriate here anyway so I'll post it. If this is against forum rules, I apologize! I'm reading a paper on decoherence (preprint http://arxiv.org/abs/quant-ph/0105127" ), and am afraid I don't grasp one...

Hi, What crystal do I need to generate polarization entangled photons? I read BBO (beta-BaB2O4) crystal are needed but when I call the engineers at commercial companies and mention the term "entangled photons" it goes way over their heads and they just say they don't make this crystal. I...

I am puzzled with the following gedankenexperiment. Consider a pair of particles that are sent from x = 0 on different directions +x and -x with entangled position on the y axis. Parallel to the y-axis we locate two double slit plates A and B. They plate A is located at x = -L and the plate B...

I've been doing more reading so forgive me. I read all the time where testing is being done with entangled particles to test their spin but no real explanation of how you entangle them. The best I can surmise is that they are two particles that have been run into each other and bounce off...

OK, here is some pretty wild stuff about entangled photons. In an experiment reported in the Preprint Archives last week, a team of distinguished physicists are continuing to push the bounds of what we can understand as "entanglement". They demonstrate entanglement of 2 photons which have...

This morning an odd thought struck me: Is it possible to consider closed (oriented) strings which are entangled into each other in target space (like two rings of a chain)? Due to the topologic properties of this construction the structure should be stable, since both strings cannot interact...

Hello, Are there any example of entangled systems suitable to show what entanglement becomes when the classical limits comes in? Have you some idea or some reference that could explicitely illustrate the transition from QM to CM for entangled system? Entanglement is often demystified by...

What do you think?

Hey all. I know it's been a long time since I have posted, but I just finished reading Entanglement: The Greatest Mystery in Physics, by Amir D. Aczel and I had a question concerning the conclusion of the work. He made the claim that GR was not violated by entanglement since messages could...

Does a single beam of entangled photons create interference? Hi, This question has come up in an FTL thread going on right now. I've seen two different answers to this question, and I'd be interested if anyone knows the real answer. Here's the setip: shine a laser beam on a crystal which...

i was just wondering, if you have two entangled particles and one of them is destroyed, does the entanglement also get destroyed, and would anything else happen?

What are Quantum Entangled Photons and how are they produced?

How do particles become entangled? I've heard that it's when two particles bump into each other. How is this "bump" defined? What does it mean for 2 particles to bump? Is it based on distance apart, or something else?

Can any "particle" become entangled with another particle Can any "particle" become entangled with another particle if it is at the same quantum state? For example if every particle in two identical human beings were entangled what would be the result? Also any help beyond those two...

Could entangled particles be used to send information instantly? For example, a Mars rover could be given a particle and Earth could be given a particle. If we did something to our particle, it would also happen to the entangled particle. We could write a computer program to interpret these...

Two photons are emitted from the same point in a crystal and they travel in opposite directions.I find the direction one photon is moving in and this means I instantly know the direction of the other photon.But the other photon had passed an event horizon into a black hole when I made my...

"Entangled Particles" Allow for absolutely crazy things? I was reading a little bit about entangled particles... I can't be sure how much of it I grasped, but as I understand it for every particle in the universe spinning in direction X, there is another particle spinning in the exact opposite...