Walter Isaacson - Einstein - His Life and Universe

That was not exactly true. A small but respectable handful of physicists soon took note of Einstein’s papers, and one of these turned out to be, as good fortune would have it, the most important possible admirer he could attract: Max Planck, Europe’s revered monarch of theoretical physics, whose mysterious mathematical constant explaining black-body radiation Einstein had transformed into a radical new reality of nature. As the editorial board member of Annalen der Physik responsible for theoretical submissions, Planck had vetted Einstein’s papers, and the one on relativity had “immediately aroused my lively attention,” he later recalled. As soon as it was published, Planck gave a lecture on relativity at the University of Berlin. 2

Planck became the first physicist to build on Einstein’s theory. In an article published in the spring of 1906, he argued that relativity conformed to the principle of least action, a foundation of physics that holds that light or any object moving between two points should follow the easiest path. 3

Planck’s paper not only contributed to the development of relativity theory; it also helped to legitimize it among other physicists. Whatever disappointment Maja Einstein had detected in her brother dissipated. “My papers are much appreciated and are giving rise to further investigations,” he exulted to Solovine. “Professor Planck has recently written to me about that.” 4

The proud patent examiner was soon exchanging letters with the eminent professor. When another theorist challenged Planck’s contention that relativity theory conformed to the principle of least action, Einstein took Planck’s side and sent him a card saying so. Planck was pleased. “As long as the proponents of the principle of relativity constitute such a modest little band as is now the case,” he replied to Einstein, “it is doubly important that they agree among themselves.” He added that he hoped to visit Bern the following year and meet Einstein personally. 5

Planck did not end up coming to Bern, but he did send his earnest assistant, Max Laue.* He and Einstein had already been corresponding about Einstein’s light quanta paper, with Laue saying that he agreed with “your heuristic view that radiation can be absorbed and emitted only in specific finite quanta.”

However, Laue insisted, just as Planck had, that Einstein was wrong to assume that these quanta were a characteristic of the radiation itself. Instead, Laue contended that the quanta were merely a description of the way that radiation was emitted or absorbed by a piece of matter. “This is not a characteristic of electromagnetic processes in a vacuum but rather of the emitting or absorbing matter,” Laue wrote, “and hence radiation does not consist of light quanta as it says in section six of your first paper.” 6(In that section, Einstein had said that the radiation “behaves thermodynamically as if it consisted of mutually independent energy quanta.”)

When Laue was preparing to visit in the summer of 1907, he was surprised to discover that Einstein was not at the University of Bern but was working at the patent office on the third floor of the Post and Telegraph Building. Meeting Einstein there did not lessen his wonder. “The young man who came to meet me made so unexpected an impression on me that I did not believe he could possibly be the father of the relativity theory,” Laue said, “so I let him pass.” After a while, Einstein came wandering through the reception area again, and Laue finally realized who he was.

They walked and talked for hours, with Einstein at one point offering a cigar that, Laue recalled, “was so unpleasant that I ‘accidentally’ dropped it into the river.” Einstein’s theories, on the other hand, made a pleasing impression. “During the first two hours of our conversation he overthrew the entire mechanics and electrodynamics,” Laue noted. Indeed, he was so enthralled that over the next four years he would publish eight papers on Einstein’s relativity theory and become a close friend. 7

Some theorists found the amazing flurry of papers from the patent office to be uncomfortably abstract. Arnold Sommerfeld, later a friend, was among the first to suggest there was something Jewish about Einstein’s theoretical approach, a theme later picked up by anti-Semites. It lacked due respect for the notion of order and absolutes, and it did not seem solidly grounded. “As remarkable as Einstein’s papers are,” he wrote Lorentz in 1907, “it still seems to me that something almost unhealthy lies in this unconstruable and impossible to visualize dogma. An Englishman would hardly have given us this theory. It might be here too, as in the case of Cohn, the abstract conceptual character of the Semite expresses itself.” 8

None of this interest made Einstein famous, nor did it get him any job offers. “I was surprised to read that you must sit in an office for eight hours a day,” wrote yet another young physicist who was planning to visit. “History is full of bad jokes.” 9But because he had finally earned his doctorate, he had at least gotten promoted from a third-class to a second-class technical expert at the patent office, which came with a hefty 1,000-franc raise to an annual salary of 4,500 francs. 10

His productivity was startling. In addition to working six days a week at the patent office, he continued his torrent of papers and reviews: six in 1906 and ten more in 1907. At least once a week he played in a string quartet. And he was a good father to the 3-year-old son he proudly labeled “impertinent.” As Mari wrote to her friend Helene Savi , “My husband often spends his free time at home just playing with the boy.” 11

Beginning in the summer of 1907, Einstein also found time to dabble in what might have become, if the fates had been more impish, a new career path: as an inventor and salesman of electrical devices like his uncle and father. Working with Olympia Academy member Conrad Habicht and his brother Paul, Einstein developed a machine to amplify tiny electrical charges so they could be measured and studied. It had more academic than practical purpose; the idea was to create a lab device that would permit the study of small electrical fluctuations.

The concept was simple. When two strips of metal move close to each other, an electric charge on one will induce an opposite charge on the other. Einstein’s idea was to use a series of strips that would induce the charge ten times and then transfer that to another disc. The process would be repeated until the original minuscule charge would be multiplied by a large number and thus be easily measurable. The trick was making the contraption actually work. 12

Given his heritage, breeding, and years in the patent office, Einstein had the background to be an engineering genius. But as it turned out, he was better suited to theorizing. Fortunately, Paul Habicht was a good machinist, and by August 1907 he had a prototype of the Maschinchen, or little machine, ready to be unveiled. “I am astounded at the lightning speed with which you built the Maschinchen, ” Einstein wrote. “I’ll show up on Sunday.” Unfortunately, it didn’t work. “I am driven by murderous curiosity as to what you’re up to,” Einstein wrote a month later as they tried to fix things.

Throughout 1908, letters flew back and forth between Einstein and the Habichts, filled with complex diagrams and a torrent of ideas for how to make the device work. Einstein published a description in a journal, which produced, for a while, a potential sponsor. Paul Habicht was able to build a better version by October, but it had trouble keeping a charge. He brought the machine to Bern, where Einstein commandeered a lab in one of the schools and dragooned a local mechanic. By November the machine seemed to be working. It took another year or so to get a patent and begin to make some versions for sale. But even then, it never truly caught hold or found a market, and Einstein eventually lost interest. 13