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Back to Einstein as the Greatest
of the Nineteenth Century Physicists
John D. Norton
Department of History and Philosophy of Science
University of Pittsburgh
What do we now think of Einstein? A famous appraisal was given byTime magazine at the end of the 20th century in its December 31, 1999 issue:
This is remarkable. Einstein's major contributions to science came in the first two decades of the centry. In spite of all that followed, he remains the Person of the Century. That is distinctive of Einstein: he was right so often.
His general theory of relativity has proven hard to test. However, after great ingenuity, when some new test is devised, Einstein's theory always prevails. There's a sense that we knew it would all along.
This was the response when the results of Gravity Probe B were reported. The probe measured the minute deviations of a satellite's motions predicted by general relativity as compared with the predictions of Newtonian theory.
Einstein properly deserves the credit. His adventurous theory has been affirmed, again.
Sometimes, matters are not so clear. In the Fall of 2011, experimenters at CERN reported an unwelcome result that they did not believe, but they could not make it go away. Neutrinos projected through the earth to a detector site in Rome were clocked at moving slightly faster than light. After considerable fuss and bother, the result was explained away, in part by a loose connection. Here's how the resolution was reported:
"Einstein was right," we are told. It's a little stretch.
It is from Einstein's theory that we do get the idea that nothing goes faster than light. However the idea that this result should be reported as Einstein being right is far fetched. Einstein's theory by itself does not prohibit faster than light particles. It requires that any such particles, should they exist, must have some rather odd properties. They would be tachyons.
More is required to rid ourselves of them. That more comes from somewhere else. Our best theory of particles like neutrinos is quantum field theory. It depends on the postulate that none of its particles can propagate faster than light.
The better caption would have been that quantum field theory was right all along. But that theory is not Einstein's.
One of the major results of recent cosmology is that the universe is expanding faster than standard relativistic cosmologies allow. To make up the difference, cosmologists have posited "dark energy." It is an odd form of matter than provides just the extra oomph needed to accelerate the distant galaxies. The great difficulty with it is that it had no other manifestation other than its power to accelerate galaxies. The idea that it is matter, as opposed to just an adjusting term in an equation, conforms to the traditional definition of an "ad hoc" hypothesis. It is an hypothesis whose truth can only be known through the anomalous effect it has been devised to explain.
It turns out that, formally, dark matter corresponds to the λ cosmological term Einstein introduced in 1917. So we now have headlines:
"Einstein proved right"??
This is odd at several levels.
The idea of an expanding universe is not Einstein's. The cosmology that bears his name was static. He introduced the λ cosmological term to make the static solution possible.
Einstein disliked the λ cosmological term. Almost immediately in 1918, he called it “gravely detrimental to the formal beauty of the theory.” He retracted it in 1932 as unnecessary when the expansion of the galaxies was affirmed. Here's the retraction in a paper coauthored with de Sitter:
The crucial passage reads:
"Historically the term containing the “cosmological constant” λ was introduced into the field equations in order to enable us to account theoretically for the existence of a finite mean density in a static universe. It now appears that in the dynamical case this end can be reached without the introduction of λ."
The cosmologist George Gamow reported that Einstein considered λ "his greatest blunder." Yet even a self-reported blunder cannot resist the idea that Einstein was always right:
If Einstein was right even in his blunders, it does not seem to far a stretch to call upon Einstein to endorse ideas that he would have viscerally opposed. String theorists number him posthumously as some sort of supporter:
String theory is not Einstein's dream. It is Einstein's nightmare. It combines the features that Einstein struggled most against. It is a fundamentally quantum theory, where Einstein felt quantum theory incomplete. It employs a Minkowski spacetime background, which Einstein believed was overcome in his greatest acheivement, general relativity.
It is an increasingly familiar idea: Einstein was so right he even somehow advocated views he explicitly rejected. Here's a report on an experimental vindication of quantum mechanical superposition.
Einstein did not think anything can be in two places at once. The non-locality of quantum theory, he maintained in his most famous critique of quantum theory, was an illusion deriving from the unrecognized incompleteness of the theory. In spite of this disavowal, we cannot shake the idea that Einstein was right and somehow this discovery proves it. The article says:
"...and concidentally proves that Albert Einstein was right when he thought he was wrong..."
I'll admit I cannot make sense of this last assertion beyond the idea that somehow Einstein was still right.
Einstein's prescience seems to know no bounds. He was even right about things over which he knew nothing. At some point, Einstein transformed from an expert in physics to an expert in insects:
A little later in the article comes the relevant claim:
"Albert Einstein, who liked to make bold claims (often wrong), famously said that “if the bee disappears off the surface of the globe, man would have only four years to live.""
Need I say it? I have found no evidence that Einstein ever made these claims about bees.
What are we to make of this? I think it can be summarized as follows:
Here is my corrective:
Copyright John D. Norton. May 4, 2012.