In the observatory’s library the day after the celebrated visit, in front of yet more photographers and journalists, Einstein recanted. Reading aloud, in his still not quite English-language English, he said, “New observations by Hubble and Humason . . . concerning the redshift of light in distant nebulae make the presumptions near that the general structure of the universe is not static. Theoretical investigations made by Lemaître . . . show a view that fits well into the general theory of relativity.”
This was big news. “A gasp of astonishment swept through the library,” the lead Associated Press reporter there wrote, for relativity mania was gripping the country. In the paper that formally announced his changed view, Einstein wrote, “It is remarkable that Hubble’s new facts allow general relativity theory to seem less contrived (namely, without the Λ-term).” It was a return to the beauty he had always loved.
Einstein had accepted lambda’s end as soon as Hubble’s findings had come out in 1929, but his trip to Mount Wilson two years later, in 1931, giving public obeisance, made it official. Punch magazine in distant England was soon writing:
When life is full of trouble
And mostly froth and bubble,
I turn to Dr. Hubble,
He is the man for me!
For a plus-fours-wearing Anglophile like Hubble, that endorsement was very good. But he was also a farm boy from the Ozarks, and so a headline that appeared several weeks before that in the esteemed pages of the Springfield (Missouri) Daily News was even better:
YOUTH WHO LEFT OZARK MOUNTAINS TO STUDY STARS CAUSES EINSTEIN TO CHANGE HIS MIND
FOURTEEN
Finally at Ease
WITH THE LAMBDA GONE, Einstein, finally, was at ease. “Since I introduced this term I had always a bad conscience,” he explained later “. . . I [was] unable to believe that such an ugly thing should be realised in nature.” The relief at being able to admit that—not least to himself—was intense.
It was too late to apologize to Friedmann, for the sorrowful Russian, undernourished, had died of typhus several years before, never knowing how much his ideas would be validated. But the portly Lemaître was still around, and Einstein was as generous as could be. At a conference in California in 1933, two years after the Mount Wilson event, Einstein stood up and said of the latest work by Lemaître, “This is the most beautiful and satisfying interpretation . . . I have listened to.”
Later in 1933, back in Brussels where they’d first met in 1927, not only didn’t Einstein try to slam a taxi door in the priest’s face, but he announced at a conference that Father Lemaître would have “some very interesting things to tell us”—which sent Lemaître into a flurry of activity before the next sessions, for he’d not known he was going to present. When Lemaître did pull together an impromptu talk, Einstein could be heard from the floor, loudly whispering in his Swabian-accented French, “Ah, très joli; très, très joli (Very beautiful; very beautiful indeed).”
Einstein was happy not just because he’d been proven right in his original symmetrical view of G=T. He also now saw that Hubble’s findings allowed us on earth to be like those Flatlanders in Edwin Abbott’s fantasy who managed to step beyond their universe and see what was really happening. A. Square had needed a visiting sphere to help him. Friedmann had suggested—also metaphorically—sending out a traveler who would march in a perfectly straight line and see if he ended up back home. Neither of those was likely to work here, but the cartographic technique that Grossmann had taught Einstein—the simple tactic of measuring the angles of triangles and rectangles to see if the figures were flat, or if their surfaces were swollen outward—was closer to the actual solution Einstein could now use.
It was a solution that Hubble himself couldn’t quite grasp. He understood that the Cepheid stars in Andromeda showed that our galaxy was just one of many other galaxies—immense islands, each containing billions of stars, that stretched far out into space: to the very limit of what the new 100-inch telescope in the mountains of California’s dry desert could detect. And Humason’s redshifts showed that those galaxies were moving away from us, and fast—and the farther away they were, the faster they were moving.
That was about as far as Hubble could go, for he would have been the first to admit that he was no theoretician. Einstein’s work already had strange consequences: the fabric of empty space rippled when Hubble climbed a ladder and “pushed” through it, and wiggling his hand made space dip and sag around it. The latest findings were even more startling. The observation through the 100-inch telescope that the far galaxies were speeding away from us would make sense if the universe had been created on a mountaintop in California, and—as if from a cataclysmic magma burst—everything was still moving outward from that point. But even the immodest Hubble couldn’t quite believe that all the distant galaxies in our universe knew where he was and that he’d be at the center of all future events, watching them recede.
The true explanation was more humbling. Imagine you’re holding a deflated child’s balloon, colored white. Now with a red marker pen put a dozen red dots on it. Start blowing up the balloon, and you’ll see that the dots will start moving away from one another.
Even better, dots that are near one another will be separating slowly. Dots that are far away will be separating faster. It doesn’t matter where you start. Look at one of the dots that happen to be at the top of the balloon. As you puff away, the dots nearest to it will move a small distance. Dots on the far side will move faster, with the whole bulk of your breath inside propelling them away. Now shift your attention to a particular one of those distant red dots. In the same amount of time that it takes for the ones nearest to it to only move a short distance, the ones farther from it will go much farther.
The effect becomes more dramatic if you imagine this happening on earth. You’re standing in London, at the Houses of Parliament, and you see the bucolic wonderland of Battersea, on the other side of the Thames, begin to move slowly away from you. That’s not too surprising, for you observe that the Thames is widening at the stately rate of 1 mph. But radio reports come in that Dublin is moving away from you at over 100 mph, and that New York—even more distant—is moving away at a rate of 3,000 mph.
That might make sense if there were some giant lava flow under the Thames pushing the earth apart, with London at the center. But then other reports start coming in, strange ones. A BBC reporter in New York insists that he feels he’s standing still. The New Jersey shore is moving away from him at a stately 1 mph, as the Hudson River slowly widens. But Toronto, farther away from New York, is receding at 300 mph, and it’s even more distant London that is receding at 3,000 mph.
This is weird, for how can both London and New York feel as if they’re the static epicenter of some giant planetary lava flow? This can only happen if the entire volume of our planet is expanding. What happens on the surface might appear odd—those cities running away from each other in this uneven way—but if you view the earth as a giant balloon or beach ball that’s inflating, it makes perfect sense. Nearby cities move apart slowly. Distant cities—distant points on the surface of the planet—move away from one another more quickly, as the entire sphere inflates.
That was effectively what Milton Humason had measured in outer space. The distant galaxies are like the dots on our balloon or the cities on our planet. And the fact that not only are they moving apart, but that regardless of which dot you are standing on, the nearby ones are moving slowly, and the farther ones are moving more quickly, can mean only one thing. What seems to us as our complete universe—the three-dimensional space we live in—is actually just the surface of something else: something huge; something terrifying. A two-dimensional balloon expands in a way we understand into three-dimensional space. By analogy, our three-dimensional universe, with all our galaxies and planets, must be expanding into four-dimensional space—a logical consequence that our limited minds can’t possibly visualize.
To Einstein, Humason’s finding was what
he’d always hoped for. The prediction contained within his original equation—what he’d mistakenly pushed away when Friedmann and Lemaître had tried to show him—was right. Our universe is just the surface of something like a giant sphere. Galaxies are scattered all over its surface, and at the moment they’re flying apart from one another, as the “underlying” sphere is expanding. We in our Milky Way are not special; no particular galaxy is. We’re all just dots on—or within—an expanding balloon. That’s disorienting for us “flatlanders” to imagine—but it had to be true, given the unambiguous measurements taken on Mount Wilson.
BY THIS TIME, in 1929 and the years right after, Einstein was much more at ease in his personal life. He and Marić had achieved an understanding, in large part because Michele Besso had acted as a calming intermediary. Einstein had also felt it only fair to give Marić the substantial Nobel Prize payment he received. She invested most of the money in rental properties. That she was financially secure made her less bitter, which in turn helped Einstein become closer with his sons. After one holiday with the boys, Einstein wrote to Marić that their good behavior showed “you have proved that you know what you are doing.”
Life was also improving with Elsa. When he’d first met her, he’d written, “I must love someone, otherwise it is a miserable existence. And that someone is you.” That initial burst of love had faded after their marriage in 1919, but gradually a surprising amount of it came back. Even though Einstein continued to have affairs, he never humiliated her directly, he was always generous, and he had a sense of humor she loved. He also recognized that even an imperfect marriage could develop its own satisfactions. Elsa thought the world of him; she was an excellent hostess, always putting people at ease; and he enjoyed her nicely ironic sense of humor.
In December 1930, for example, when they arrived in California for the inspection of Hubble’s results, among the waiting crowds were several dozen cheerleaders. The sight had struck them as so preposterous that Elsa decided to inspect them as if they were a military guard—walking along and murmuring suitable comments about their appearance, much to her husband’s amusement.
Nothing flummoxed her. Another time, when visiting the University of Chicago with Einstein, she talked about a recent stay in Princeton, saying that she and her husband had liked it very much, despite the difficulty with the flying snakes. The interviewers were confused, so Elsa elaborated: the flying snakes that bit her on the hands. They were more confused, so she went on: the same flying snakes that had flown up under her skirt! It was at that point that a bilingual hostess stepped in. Was it really flying snakes? she asked Frau Einstein in German. Elsa shook her head. Americans could be so naive. “Nein!” she explained. “Ich spreche von Schnaken (I’m talking about mosquitoes)!”
At their home in Berlin, Elsa took great care to ensure her husband’s comfort. Einstein loved fresh strawberries, for example, so she bought them whenever possible. The couple had a blue parakeet, which made the kitchen pleasant, and they hosted musical nights, too. Einstein also had plenty of time to relax with the piano or his beloved violin on his own, even though the neighbors did not appreciate him playing it quite so vigorously in the echoingly tiled kitchen at night.
Even stays at their summer house often led to good times. Einstein loved sharing walks and the beautiful views with Elsa and his stepdaughters. His son Hans Albert, now more reconciled with him, at least once showed up on a motorcycle, to everyone’s fascination. There was mushroom hunting in the woods, the strange “yo-yo” toy a neighbor’s son let them try, and the fruit trees and shady porch. It was to Hans Albert that Einstein had said his wife was “no mental brainstorm,” but then he had gone on and added, “[Yet] she is exceptionally kindhearted.”
Elsa’s daughters seem to have taken their stepfather’s side and concluded that the trade-off of accepting his affairs was more than worth living with “Father Albert.” And whenever he really had to, Einstein drew back to protect his marriage. In 1924, for instance, he had written to one exceptionally besotted young university graduate that there was going to be no future for them and that she should simply “find somebody who is ten years younger than me and loves you just as much as I do.”
As Einstein’s family life had stabilized, he had achieved equilibrium in other ways as well—or so, at least, he thought. The reason he felt this way can be seen in his reaction to a particular contribution by the man who had once been a thorn in his side: Lemaître.
Back in 1927, before Einstein had decided to get rid of the lambda, he had been rude to Lemaître, not giving his work serious attention. This had hurt the inexperienced Belgian, leaving him dejected. After finally getting Einstein’s support, however—as well as that of Eddington and everyone else who counted—Lemaître’s confidence was back. He began to look a bit more at the dynamics he’d pulled out of Einstein’s raw equation. The universe might be expanding, or—in line with Friedmann’s vision, which so uncannily matched Hindu myths—it might be constantly cycling back and forth, as if it were “bouncing” in size. Yet both of those views presumed that this was a process that had always been taking place: that there had been no creation, just as there would be no end.
Why?
For the rest of his life, Lemaître insisted that what he did next had nothing to do with his religious beliefs—that religion was one path to the truth and science was another, and the two could operate quite independently of each other. But papers discovered after his death show that even when he was still in training for the priesthood, in the seminary, he’d jotted a note to himself: “As Genesis suggested it, the Universe had begun by light.”
Now, newly confident in the years after 1929, he began to see how that idea, too, might be hidden within Einstein’s raw equation. Couldn’t one simply travel backward in time and see what it all must have started from? With the Mount Wilson measurements, these sorts of reflections were not entirely theoretical anymore. Humason had shown that some galaxies were hurtling away from us so fast that yesterday they had been perhaps a billion miles closer, and the day before that two billion miles. All the galaxies beyond our local cluster had once been closer. It was as if a giant grenade had gone off long ago, sending fragments—these galaxies—flying outward. We arrived very late on the scene and could only see those flying fragments. But in our mind’s eye, we could work backward, and backward, until we reached the initial moment of the explosion—what Lemaître called “A Day Without Yesterday.”
Lemaître published his new calculations in 1931. They were more complicated than the preceding summary, for instead of imagining the primordial “atom” as a glob of matter inside a region of space, we had to imagine space and time itself whooshing to a more tightly compressed point. Our mathematics can be precise, but our mental visions—and our words—have to remain metaphorical. Lemaître gave it a go, saying, “The evolution of the universe can be likened to a display of fireworks that has just ended: some few wisps, ashes and smoke. Standing on a well-cooled cinder, we see the fading of the suns, and try to recall the vanished brilliance of the origins of the worlds.” That was, in fact, what Einstein in 1933 called “the most beautiful and satisfying interpretation of creation I have listened to.”
Lemaître’s theory of the origins of the universe was stunning. It was revolutionary. And it—like so many other seminal achievements in theoretical physics—owed everything to G=T.
Both good and bad came from the rehabilitation of Einstein’s original gravitation equation. The pleasing consequence was that Einstein—and all those who understood his equation—had just seen one of the most astonishing aspects of science: humans can write accurate equations that are “smarter” than the people who devised them, in the sense that these equations can produce stunning, accurate predictions that their creators never realized were there. A mere mortal, sitting in his study and strolling the streets of Zurich or Berlin, had been able to use pure thought to come up with the idea that G=T, and in so doing had opened the floodgates of the
many astounding—and, frankly, unimaginable—predictions that then came pouring out of it.
Even more satisfying for Einstein was the belief that his thoughts had revealed that the universe is tidy: built on exquisitely clear principles. This architectural unity is what Einstein had always loved. In getting rid of the lambda, he received confirmation that this crisp reality truly was out there, waiting for humans to discover it.
The other consequence was less positive.
Geniuses have to push hard to come up with their first ideas. Almost always, they’re going far past what everyone assumes to be true and have to be confident that they’re right. That involves being stubborn. But they also need to be supple, making sure their breakthroughs incorporate all the relevant factual information, then keeping their later work responsive to what others are finding out, too. The trick is to surf this line between the supple and the stubborn without straying too far to either side.
Einstein was about to break that balance. He had only added the ungainly lambda to his equation because Freundlich and the other astronomers working in 1915 and 1916 hadn’t known about the universe’s expansion. If they had possessed all the facts, they never would have opposed him, and he wouldn’t have done such a thing. Never again, he vowed, would he be duped in the same way; never again would he let the limited state of experimental knowledge make him undermine what he was convinced was a pure, attractive theory.
Einstein's Greatest Mistake Page 15