LIGHTS ALL ASKEW IN THE HEAVENS
May 29th is the centenary of Sir Arthur Eddington’s eclipse experiment, which proved Albert Einstein’s general theory of relativity.
“A young German physicist, Albert Einstein, had worked tirelessly on his new theories of relativity beginning with his first published papers in 1905, and culminating with his magnum opus ‘General Relativity’ in 1915. Only a handful of physicists had apparently paid Einstein’s latest creation much mind. One of these was Sir Arthur Eddington in England.
“One of the predictions made by Einstein was that, in the presence of a gravitating body, space would be bent causing light rays to take a different path than predicted by Newton’s physics. Eddington soon realized that this light deflection could be measured by looking at the positions of stars before and after a total solar eclipse. The May 29, 1919 solar eclipse was perfect for this task because of its unusual length (6 minutes) and a track that passed over countries not involved in World War I. It was at that time that Einstein’s new, but entirely obscure, theory of gravity would be pitted against that of the physics Grand Master, Sir Isaac Newton. Through the action of warped space surrounding the sun, the sun would act like a colossal lens, deflecting the images of stars near its occulted limb.
“Calculations made with the help of Newton’s theory of gravity and motion also predicted such deflections of starlight, but by exactly one-half as much. The deflection was invisible to the human eye, but the fact that it occurred at all, and by a specific amount, was the key that led to a major revolution in physics. Some say that, were it not for this spectacular discovery, all of Einstein’s relativity theories would have languished for many more years.”
—Technology Through Time, Issue #44: Einstein (NASA)
“The predictive power of Einstein’s theory—the fact that it offered up a testable prediction—perhaps exercised a power over Eddington, whose admiration for the mathematical elegance of the theory caused him to believe in it deeply. He discarded the lower value coming out of Brazil, contending that the equipment was faulty, and with a slight bias toward his own fuzzy results from Africa got an average of just over 1.7 arc-seconds, matching Einstein’s predictions. It wasn’t the cleanest confirmation, but it was enough for Eddington, and it turned out to be valid. He later referred to getting these results as the greatest moment of his life.”
This event will be celebrated in a PBS special by Brian Greene; it’s entitled Light Falls.
My co-writer Shelly Berg and I wrote a song called “Some Kind of Einstein” for my 2018 album Math Camp; the lyrics reference the Eddington experiment. There’s a quote in them by Stephen Hawking: “It turns out to be very difficult to devise a theory to describe the universe all in one go.” Here’s the rest of that quote. In the late 1960s, Hawking and his Cambridge friend and colleague, Roger Penrose, applied a new, complex mathematical model they had created from Einstein’s theory.
SOME KIND OF EINSTEIN
Music, Shelly Berg/Lyrics, Lorraine Feather
When you were a little fellow, five years old,
You became incredulous at the
Magnetism in a pocket compass.
You were knocked sideways by the mystery—
Something powerful you couldn’t see.
Inside the laboratory of your big brain, you
Took apart the notion of a straight line,
Thought up what had been theretofore unthinkable.
You must have been some kind of Einstein.
Some of us paint,
Some of us play.
Some of us pay elaborate attention.
Some of us cook,
Some of us bake,
Some of us make a puzzle out of nothing,
And go, “Aha!”
“Men of Science More or Less Agog,” it read
In the Monday morning Times. You had
Laid to rubble, all their former paradigms.
With no more than math, you concluded that
Space and time were supple as a cat.
It couldn’t be appreciated widely,
Not comprehended through a pithy headline,
But those who understood it were forever changed.
They saw you were some kind of Einstein.
Some of us write,
Some of us draw
Upon the awful loveliness of nature.
We can be bright,
We can be dim,
Or have unlimited imagination.
We go, “Aha!”
“It turns out to be very difficult
To devise a theory
To describe the universe
All in one go.”*
We could wait for 10 or 20 centuries
For a simple answer to the whole dang thing.
Who will do the final theorizing?
They could be an alien in 3309,
Or, as I sing,
Be driving down the California Incline,
But’s it’s a certainty
They’ll need to be
Some kind of Einstein,