From Walter Isaacson’s Einstein: His Life and Universe:
So it was that Albert Einstein would end up spending the most creative seven years of his life— even after he had written the papers that reoriented physics— arriving at work at 8 a.m., six days a week, and examining patent applications. “I am frightfully busy,” he wrote a friend a few months later. “Every day I spend eight hours at the office and at least one hour of private lessons, and then, in addition, I do some scientific work.” Yet it would be wrong to think that poring per applications for patents was drudgery. “I enjoy my work at the office very much, because it is uncommonly diversified.”
He soon learned that he could work on the patent applications so quickly that it left time for him to sneak in his own scientific thinking during the day. “I was able to do a full day’s work in only two or three hours,” he recalled. “The remaining part of the day, I would work out my own ideas.” His boss, Friedrich Haller, was a man of good-natured, growling skepticism and genial humor who graciously ignored the sheets of paper that cluttered Einstein’s desk and vanished into his drawer when people came to see him…. Indeed, we should not feel sorry for Einstein that he found himself exiled from the cloisters of academe. He came to believe that it was a benefit to his science, rather than burden, to work instead in “that worldly cloister where I hatched my most beautiful ideas.”
Every day, he would do thought experiments based on theoretical premises, sniffing out the underlying realities. Focusing on real-life questions, he later said, “stimulated me to see the physical ramifications of theoretical concepts.” Among the ideas that he had to consider for patents were dozens of new methods for synchronizing clocks and coordinating time through signals sent at the speed of light.
Peter Galison’s book Einstein’s Clocks and Poincare’s Maps does a really great job of teasing out how the patents Einstein was reading— about times standardization and synchronization— were raising some of the same questions he was grappling with in his scientific work.
If you want the short versions, Galison discusses his argument in a conversation with Graham Burnett. I’ll just note this one bit, where Galison talks about how we traditionally believed that “Einstein at the patent office is the genius at his day job: at best a source of bread and butter, at worst a distraction, but in some deep way irrelevant to understanding his science.”
Burnett: When did you begin to get a different idea of how the story might be told?
Galison: I was standing at a train station in northern Europe admiring a line of clocks that went along the platform. And I noticed that the minute hands were all at the same point – I could just see them all lined up. I thought, “These are wonderful clocks; isn’t that impressive that they can make them to hold such regularity?” Then I noticed that the second hands were clicking in synchrony too, which was startling, and I thought, “These can’t be that accurate – you can’t have clocks running like this that are not synchronized in some way, or else they’d get out of phase.”
Suddenly I wondered if Einstein had paid attention to synchronized clocks in train stations. If he had it would give a very tangible sense to that most famous of all scientific thought experiments in his 1905 paper. It would make his move towards a criticism of absolute time both figurative and literal. So I went back and I started poking around – and found myself in the midst of an absolutely immense literature on fin-de-siècle timekeeping and clocks. As you know, there was at the time an urgent technological problem of coordinating time along train tracks. More than that: in Europe the center of precision-coordinated timekeeping was Switzerland, and if all this industry was based in Switzerland they must have been processing patents right and left.
I went to the patent office, and found myself surrounded by a huge number of patents with diagrams of clocks linked by signals. There were even proposals for patents and articles in the technical journals about clocks linked by radio waves. All this seemed extremely close to the kind of materialization of time that preoccupied Einstein. Of course, the clock factories and inventors had no interest in “frames of reference” or in all the “physics of the ether.” But the importance of distributing simultaneity by electromagnetic means was clear to everyone. Here was a technical problem located in Switzerland, centered in Berne, and with ideas coming to a point in Einstein’s patent office. It all seemed remarkable; and it is there that I began this work.
So not only is Einstein doing some of his most creative work in the Patent Office; he’s encountering issues that feed pretty directly into his scientific work.