Quantum Entanglement is THE mystery in physics. Entanglement is the thing that makes the quantum world, “different”. It is what is behind the two slit paradox. This is what Einstein called “spooky action at a distance.”
Of all the things in particle physics for which there are no explanations, entanglement is the biggest. If it weren’t demonstrably true, no one would be able to believe it. But physicists have already used entanglement to transport matter. Yes, like in Star Trek.
No, I am not kidding.
No one understands or can explain entanglement. It is very hard even to describe. Not being a mathematician, I still have trouble understanding the two-slit experiment in a satisfactory manner. It is hard for me to comprehend what they mean when they say “observe” a photon. If an atom were the size of a bus, then the kind of “observation” physicists do is crash a motorcycle into it, right? Surely we would not be surprised, after this event, to notice that we had “affected” the outcome. Duh. Yet this is what so many of these experiments seem to be saying. I am missing something there. I have not posted on the two slit experiment (yet). I am still looking for a better explanation.
I will say this: if the particle detector “collapses the wave function” then the particle detector, like the phosphorescent plate that records the pattern on the other side must be creating the particle, or causing the particle to condense, which may not be that mysterious. Instead of thinking of collapsing wave functions, think of water droplets condensing out of thin air. Maybe that will help. The particle-wave duality may be nothing more mysterious than the liquid-gas-solid trinity.The question then becomes: what is the mechanism that causes this condensation? I would think that the collapse is the result of some basic, atomic interaction such that the particle condenses out of its wave state quite readily when it meets matter and the whole mystery is based simply in this condensation process, which is not currently understood very well.
OK, so here is my attempt at explaining entanglement:
The story goes that a photon is fired into a crystal that splits the photon into two photons that are then entangled. The two photons shoot off in different directions. Photon A goes to detector A and photon B to detector B. The detectors can be any distance apart.
OK, here it goes: if you alter the orientation or spin or polarization, or whatever, of photon A, this will cause a change in photon B!
In other words, we have two separate objects that are connected in some mysterious way other than through space and time. In other words, they are connected, beyond space and time. Spooky action at a distance!
Now, I am sure there are all kinds of theories to explain this, but the most obvious one is that they are connected in some other dimension. I have not heard of such an explanation, but if you follow the logic, this seems a basic conclusion, unless for some other reason we cannot allow for “other” dimensions.
So that is what I am going with. It makes sense that the two photons, being derivatives of the original photon, are still one. It is only their “shadows” on the dimensions of space-time that are separate. Looked at in this way, it does not seem so strange, except it forces us to start adding dimensions to our perception of the universe. Yet this is hardly anything new.
This view is in line with the De Broglie/Bohm interpretation of quantum mechanics, which is opposed to the Copenhagen interpretation, put forth by Neils Bohr. As much as I like the mystical feel of the Copenhagen interpretation, I really think we will find that the De Broglie/Bohm interpretation – that there is yet something hidden from us that will explain all of this in a classical, cause and effect way. For example, a hidden dimension in which the photons are connected, non-locally.
This could also explain the two slit experiment. If there were “unseen” aspects to a photon such that we were in fact collapsing the wave function when we place detectors in one of the “paths” then this would explain why the interference patterns disappear, even when the detector is placed in one of the paths after the slits. We deduce that the photon goes through both slits, even though we can only ever “detect” that it goes in one or the other. This is the paradox of the two slit experiment. What we see happening does not match what we conclude must be happening, as the interference pattern clearly indicates. So you have a situation where what happened, happened undetected. So I posit that the photon does go through both slits, but that there is a “part” of the photon that we do not detect! And yet it seems this non-detection on our part has the effect of collapsing the wave function and removing the interference pattern.
I call this the Invisibility Principle, or maybe the Imaginary Principle. Apply the same technique that we use to understand complex numbers, and now imagine that the photon too has a “real” part and an “imaginary” part. Like with the complex number, which has literally jumped off the number line into another dimension of space, envision the photon likewise. If you imagine the electro-magnetic wave propagating at right angles to each other, you can imagine some other wave propagating at a right angle in a non-space dimension that we can’t detect. Of course, this may well be pure fantasy. It certainly is not founded in mathematical formulation. Wait, what? Strings? You say you do have the mathematical formulations for these extra dimensions? And a very strong theory that could unify the forces?