Crystal for entangling photons. |
This is not a wish that I share. It is bad enough that the industrial zones of so many North American cities are cluttered with mini-warehouse units where the divorced or otherwise unsettled deposit stuff for which they lack space to use. The addition of units for the storage of frozen cadavers would only add to the dismal character of such neighborhoods, and would, in the event of a power outage, create an intolerable stench.
One thing, though, that is appealing about the possibility of returning to life after a century or two, is the prospect of learning how certain presentday developments turned out, for example, problems in quantum physics.
In particular, one would like to know more about what Einstein called "spooky action at a distance," which is manifest when associated particles are shot off in different directions while nevertheless maintaining a mysterious connection, referred to as entanglement.
For example, if Bob examines one of a pair of entangled photons and determines that it is polarized up, he knows that its entangled partner, though perhaps light years away, will, if immediately examined by Alice, turn out to be polarized down, as Alice can report back by snail mail.
Now to anyone who is almost totally innocent of an understanding of quantum theory, as I certainly am, the obvious explanation for these facts is that the pair of photons that Bob and Alice examined always were polarized up and down, which is why Bob, discovering that his photon is polarized up, knows immediately that Alice's photon is polarized down.
But, say the physicists, no, the polarization of a photon is determined only when someone looks at it, and it is this fact that makes the instantaneous connection between entangled particles "spooky," because nothing, including information, travels faster than light, therefore this instantaneous relationship between the photons, however far apart they may be, is impossible.
Actually, the physicists don't say it's "impossible," since that's what they observe. But it's a problem.
The physicist David Bohm offered and explanation based on the postulated existence of "hidden variables." I hardly know what a variable is, but perhaps the idea is that although the polarization of a photon is not determined before you look at it, there is something traveling with a photon that tells it how to polarize when you do get around to looking at it. This thing, whatever it might be, I think Bohm called it a "signal wave," by accompanying both entangled particles could then dictate how each photon polarizes when examined.
If my interpretation of Bohm is correct (I hope some physicist will correct me if I am wrong), although the polarization of entangled photons is not determined until someone looks at them, the way each photon polarizes when looked at is predetermined.
Another idea, and this is my own original contribution to physics, is that information really does flow between entangled particles, and that although the speed of this information flow is restricted to the speed of light, communication between the particles appears instantaneous because the information travels via one of those extra dimensions that the string theorists talk about. You know, one of those little "curled-up" dimensions. Thus, particles at unimaginable distances in our four-dimensional space-time world could remain in intimate conversation, only millimeters apart, in some little rolled up dimension of which we are presently only rather uncertainly unaware.
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