In 1935, Einstein and two colleagues published a paper that set off what has become close to a century of theorizing and research about entanglement phenomena.
The paper came to be known as EPR from the initials of the last names of its authors – and while they may not have had me in mind at the time, I have always been grateful to them for marking the year of my birth with such a monument.
Photons (and other particles plus atoms and even some small groups of atoms) that become entangled are entities that come to share the same quantum state and thereafter instantaneously change their quantum states in sync no matter how far in space they may be separated. The situation is still far from completely sorted out, but scientists have experimentally verified the action-at-a-distance instantaneous state changes.
Make no mistake: This is a strange way for things to turn out in science. (Einstein himself called entanglement phenomena “spooky” behavior.)
Think about it: Two entangled photons could originate from the same event in a distant galaxy, and if these particles are emitted in exactly opposite directions and stay in the same state until one of them registers on your retina, that event will simultaneously change the state of the photon striking your eye and the state of its entangled partner or partners – even if they are separated in space by billions of light years.
(Ah, little did you know the havoc that you wreak in the universe each time you look at a sky filled with stars.)
On the surface, this phenomenon seems to violate the principle that nothing can travel faster than the speed of light because it is difficult to see how this action-at-a-distance could occur without something traveling instantaneously between the two (or more) entangled particles.
So, the bottom line, at least among naïve folks like me, is that it seems as if the universe has a built-in tracking-and-control system to constantly monitor all photons to determine which ones become entangled and which ones don't and to issue control signals to sync quantum states as required. And the same would be true for everything that is subject to entanglement up to and including – the last time I checked – small groups of carbon atoms.
Now, I have to admit that my understanding of entanglement depends almost entirely on informal, popular sources and that I have not updated myself even on that level in any substantial way since Brian Silver's The Ascent of Science (Oxford University Press, 2000) appeared.
But from what I can glean in a casual way from the current, more technical articles in Wikipedia, the situation has evolved in complexities, not in substance over the past 14 years.
And since this tracking of states and responding to events is so similar to the way that a living organism with a sophisticated nervous system routinely senses the state of its body parts and changes its behavior on the basis of that information, I have to wonder not only whether the universe is a living organism – but whether it may also have the thing we call a mind.
Is it true, perhaps, to paraphrase Louisa May Alcott – that not a photon falleth from a higher quantum state but the universe doth know?