Entanglement

It Baffled Einstein, But Suggests a Whole Different Outlook on the Universe

Einstein called it “spooky action at a distance” and quipped, “God does not play dice with the universe!” But apparently, He does. Mind-bending experiments have seemingly invalidated the speed of light (186,000 miles per second) when two protons shot in opposite directions sped away from each other at that speed. A measurement of one of the two protons affected the other one instantaneously, although theoretically communication between them was impossible. Here is one recent explanation by a physicist.

In the Wikipedia article on Quantum Entanglement, it says:

Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, is found to be anticlockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a particle’s properties results in an irreversible wave function collapse of that particle and changes the original quantum state. With entangled particles, such measurements affect the entangled system as a whole.

Apparently some things in the universe are linked together in ways we do not yet understand.

At the same time, I think people are also similarly “entangled.” For example, I firmly believe one cannot avoid auto accidents without being able to make a good guess whether the other driver (whose face you have not seen) is going to cut in front of you. Unless I am distracted by conversing with a passenger, I am pretty good at “reading” traffic. How is that possible?

Then there is the whole question of presentiments of disaster which are proven to be true, There have been studies that people who have survived disasters had some foreshadowing of what was to occur. Does that mean that people are in some strange way entangled with events?

We are used to seeing people, things, and events as existing in separate “boxes.” What if some elements are in fact separate, and others are interlinked in ways we cannot foresee? Perhaps in future scientists will be able to describe how some of these entanglements work. Until then, we will just have to open our minds to a certain degree of strangeness. Which is probably a good idea in any case.

More “Spooky Action at a Distance”

The Theory Has Been in Play for More Than a Century

Mention Quantum Theory to a non-scientist, and what you frequently get in response is a look of profound puzzlement. Even Einstein has weighed in against many of its premises by calling it “spooky action at a distance.” Elsewhere, he asserted that “God does not play dice.” I mean, if Einstein wasn’t on board with this, how could it be true?

Close to the center of the theory is what is called the Copenhagen Interpretation, proposed by Niels Bohr and Werner Heisenberg around 1925-1927. According to it, in the world of micro particles, there are no equivalent certainties to the world of big objects like stones, trees, or even planets. If you set up an experiment such as the one illustrated below in which a photon is fired at an opaque object in which two slits are cut, the end result on a receiving surface is not nice and predictable. At times, it will seem that a single photon will go through both slits simultaneously, which would seem to be impossible. At times, when light is shone through the slits, it will seem that the light will act as if it were a particle; other times, it will act as if it were a wave.

The Two Slit Experiment Presents a Multiplicity of Results

Every few years, I read another book on quantum theory to see what physicists are doing with it. Currently, I am reading Through Two Doors at Once: The Elegant Experiment That Captures the Enigma of Our Quantum Reality by Anil Ananthaswamy. Like most books on the subject, there is a heavy reliance on the history of the theory over the last hundred years or so, ending with experiments currently in play.

It’s hard to believe that such a simple experiment could flummox so many incredibly smart people, but it does. And it even still flummoxes me.