Thursday, June 2, 2011

Entangled in Spooky Science

Spooky science sells better than serious science, especially when science requires mathematics beyond 99% of the population's knowledge. The June 2011 Scientific American issue includes an article by Vlatko Vedral, Living in a Quantum World, that emphasizes one spooky corner of reality, quantum entanglement. This is also a favorite topic of New Age purveyors of spooky religious viewpoints, as if it might provide a physical basis for ESP and other tricks of the trade.

We are spooked by the unfamiliar. Familiar things that should be totally amazing, like transistor radios and lasers, which rely on quantum mechanical effects, don't faze us at all these days. We don't have to understand new technologies to stop being spooked by them, we just need to see them in action for a while.

I would argue that quantum physics has few new philosophical implications. It is no where near as revolutionary as what we now call Classical physics.

Classic is one of those words we need to be careful about. It used to allude to the culture of the ancient Greeks and Romans, let's say from 500 B.C. to before the Christ cult took over in the 4th century after Augustus Caesar. In physics it means, roughly, how the world was conceived of by scientists from the era of Galileo and Copernicus until Albert Einstein's four famous papers of 1905.

Classical physics was pretty darned spooky stuff. Not really believable, unless you looked at nature with a great deal of care. Before classical physics there was ordinary human intuition based on experiences in the world, and there was the physics of Aristotle and his cohort of Greek geeks. Today seven year olds know about dinosaurs and galaxies, but no one knew about them in 1400. Except for a very few people who studied the Greek classics (and the equivalents of other civilizations, notably the Arabs, Indians and Chinese), experience was limited. Water flowed downhill, the seasons were reliable, the stars rotated around Polaris, and no one had built a decent sewer system since the fall of the Roman Empire.

For Aristotle objects moved only when under the influence of a continuous force. People familiar with Newton's first law of motion (previously stated by many others, especially Islamic scientists), that an object's velocity remains constant unless acted on by an external force, may laugh at Aristotle. But in the everyday real-world Aristotle is right and Newton is wrong. Aristotle correctly believed there is always friction; he argued that vacuums, required for friction-free maintenance of velocity, cannot exist. The best modern car running on a flat road need gas, and the force from its engine, to maintain a constant speed to overcome friction. For Newton's version of the law to work you need essentially imaginary conditions: a perfect vacuum, which you can't find even in inter-galactic space.

The idea of continuing motion without a force behind it was spooky; it still is if you think about it too much. But it was not as spooky as the revelation that the earth revolves on its axis. We seem to be relatively motionless, hugging mother earth, but we are not.

Electricity and magnetism are part of pre-1905 physics. Talk about spooky. Both were believed by religious types to be the physical basis for ESP and hypnotism (called personal magnetism). Both exerted force at a distance. It took decades of experimenting and thinking to figure out their basic laws. But people got used to them. They got used to the telegraph, electric lights, and telephones.

Other people, including scientists, had trouble with Albert Einstein's work on relativity. Einstein himself had lots of trouble with the concepts of quantum physics, even though he was one of the inventors of the inventors of the field. He called quantum entanglement "spooky action at a distance." This from a guy whose father and uncle had a successful 19th-century electromagnetics business. (Which is why doing well in elementary school was not all that important to his future success.)

Context is as important in the natural sciences as it is in philosophy or dealing with various human cultures. Vedral's "Living in a Quantum World," makes the case that quantum effects can show up in our macro world. In particular he wrote about quantum entanglement. It is interesting stuff, and I applaud those who have figured out how to extend our knowledge of this subtle phenomena. But be forewarned, this is the stuff New Age con artists use to bamboozle their soft-brained victims.

Beware of physics writers over generalizing. Vedral uses the phrase "Quantum mechanics says ..." Quantum mechanics does not say anything. Physicists say things, and they often disagree with each other, especially about quantum mechanics and its philosophical interpretations. As a group they like to say that quantum mechanics has a long history of making correct predictions as verified by experiments. But in fact, as illustrated in, for instance, Abraham Pais's Inward Bound: Of Matter and Forces in the Physical World, quantum mechanics has a long history of missing on as many predictions as it hit. Today's quantum mechanics is not the quantum mechanics of 1940. The math has often been fudged after the experimental results were known. That is fine, fixing a theory is part of the process of science.

It does not serve science, however, to pretend that a theory developed in the 1920's accurately predicted all the results known today.

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