The American Spectator

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Einstein's Revolution, and Counterrevolution

By Tom Bethell on 6.21.07 @ 12:06AM

(Page 2 of 3)

SPECIAL RELATIVITY MAKES VERY Peculiar claims. You and I, next to one another, carry identical rulers and wear exactly synchronized watches. When I move, I see your ruler shrink and your watch slow down. You observe no such changes -- called time dilation and length contraction -- but you do see my ruler shrink and my watch slow down.

So, exactly the same question that Einstein asked of quantum mechanics could be asked of relativity.

Isaacson: "Some may be tempted to ask: Which observer is 'right'? Whose watch shows the 'actual' time elapsed? Which length of the rod is 'real'?" Mindful of the perplexing history here, he diplomatically finesses the question ("it is not a question of whether rods actually shrink or time really slows down...").

At the end of a new book called It's About Time, the recently retired physics professor N. David Mermin, who taught relativity at Cornell for decades, asks the same question. He asks of moving sticks and clocks that allegedly shrink and lag: "Do these things really happen, or are they just secondary manifestations... leading to disagreements about what constitutes a valid measurement?"

Mermin's answer is one that you might consider surprising in a book published exactly 100 years after Einstein's theory was invented:

There is by no means unanimity among practicing physicists on this question, and one frequently finds assertions that, for example, moving clocks appear to run slowly when measured by stationary ones, or that moving sticks appear to shrink.

Here is Arthur Eddington, the famous British astronomer who led the 1919 eclipse expedition that confirmed Einstein's prediction about the bending of starlight grazing the sun. Eddington wrote: "The shortening of the rod is true, but it is not really true. It is not a statement about reality (the absolute) but it is a true statement about appearances in our frame of reference."

Got that? It's in Eddington's The Nature of the Physical World (1928). There's an apocryphal story about Eddington. Someone told him he was one of only three people who understood the general theory. He is said to have replied: "I'm trying to think who the third one is." By the way, the bending of starlight is really real, and it confirms something important that Einstein had written in 1916. "The principle of the constancy of the velocity of light in vacuo must be modified." Yet that principle had been central to special relativity.

Isaac Asimov posed the same question about shrinking sticks and lagging clocks in 1966: "Which [observer] is really 'right'? The answer is neither and both," he wrote.

Many such examples could be given. There is something unsatisfactory about such a theory, surely. Experts cannot agree whether its most famous predictions -- that time goes more slowly and lengths contract in things that move with respect to an observer -- are real or not.

Here's a simpler answer to the above question: Length contraction has never been measured at all. Not once. Sticks "really must" behave in this odd way, says Mermin, but only in the sense that it follows mathematically from the two postulates on which Einstein's special theory was based. But it has not yet been observed.

As to time dilation, it has been shown that particles moving at high speed through the Earth's gravitational field survive longer than slower-moving particles, and this has been construed as evidence for time dilation. But it is a very weak confirmation, with a simpler explanation. Saying that atomic clocks (or particles) slow down under certain conditions is not the same as saying that time slows down.

MAYBE YOU CAN SEE WHERE this is going. The consensus among physicists is that Einstein erred in his stubborn and "conservative" resistance to the Copenhagen interpretation of quantum mechanics. It was with relativity, in his gloriously rebellious youth, that he scored his great triumph. This is Isaacson's view. In all things he quietly sides with the consensus, brings diplomacy to bear on every controversy, promotes no novel interpretation, upsets no apple carts, and is at all times moderate and balanced. Given his position, and the book's ambition, this is to be expected. We don't expect a work that aspires to be (and is) authoritative to adopt controversial positions.

To me, however, Isaacson's Einstein unexpectedly reinforces a contrarian view that I have long entertained. It is this: that Einstein was right about quantum mechanics, and will eventually be vindicated. Furthermore, sooner or later his much admired notions about relativity will have to be discarded.

This is not just cussedness, although it may betray a conservative bias. Science, I believe, can be radical (in the sense of going to the roots) and it must be innovative. But it can hardly be "revolutionary"; it cannot dig up those roots and overthrow the fundamentals, as special relativity did with space and time.

The emeritus Caltech professor Carver Mead writes in his book Collective Electrodynamics that new researchers (he mentions several unfamiliar names) "have put us in a position to finally settle the Einstein-Bohr debate -- with a resounding victory for Einstein." Mead also said in an interview that Bohr & Co. "took the limitation of their cumbersome experiments as evidence for the nature of reality." Likewise, Einstein's views about space and time were based on experiments using 19th-century equipment.

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