Credit: Matt Aze.

Here's the simplest explanation for what you're seeing that we could find: 

When we measure both [entangled] members for color, or both members for shape, we find that the results always agree. Thus if we find that one is red, and later measure the color of the other, we will discover that it too is red, and so forth. On the other hand, if we measure the shape of one, and then the color of the other, there is no correlation. Thus if the first is square, the second is equally likely to be red or to be blue.

We will, according to quantum theory, get those results even if great distances separate the two systems, and the measurements are performed nearly simultaneously. The choice of measurement in one location appears to be affecting the state of the system in the other location. This “spooky action at a distance,” as Einstein called it, might seem to require transmission of information — in this case, information about what measurement was performed — at a rate faster than the speed of light.

But does it? Until I know the result you obtained, I don’t know what to expect. I gain useful information when I learn the result you’ve measured, not at the moment you measure it. And any message revealing the result you measured must be transmitted in some concrete physical way, slower (presumably) than the speed of light.

Upon deeper reflection, the paradox dissolves further. Indeed, let us consider again the state of the second system, given that the first has been measured to be red. If we choose to measure the second q-on’s color, we will surely get red. But as we discussed earlier, when introducing complementarity, if we choose to measure a q-on’s shape, when it is in the “red” state, we will have equal probability to find a square or a circle. Thus, far from introducing a paradox, the EPR outcome is logically forced. It is, in essence, simply a repackaging of complementarity.

In order to account for the results of our new experiment, the unknown mechanism would need to have been set in place before the emission of the starlight that Handsteiner’s group observed, back when Joan of Arc’s friends still called her Joanie.

Tangled up in q? Experimenters explain how they increased our certainty of quantum entanglement by a factor of "ten million billion."
↩︎ The New Yorker
Feb 16, 2017

Quantum entanglement vexes us now. It might save us soon.

After all, with it we could...

—Build a better time capsule. You can use it to encrypt information that is impossible to decrypt until a specific moment in the future

—Sort large amounts of information quickly. And not just information, but atoms. Which means Star Trek replicators are on the horizon. 

—Model chemical reactions as never before. Because molecules are highly entangled, understanding entanglement was the key to the first perfect simulation of a molecule.

Feb 16, 2017

Whether Trudeau rehearsed this as a stunt or not, it's actually kinda helpful. 

Mathematically, entanglement in time is identical to entanglement in space, and we have no qualms with information traveling in all directions across space.

It's hard for us to fathom, but if you choose option c), time travel, then quantum physics actually starts to make sense.
↩︎ Quanta
Feb 16, 2017
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