The Time Zone Keeper
Alumnus Paul Eggert has spent two decades maintaining the internet database that synchronizes our digital clocks.
Spring 2025
By Scott Pett ’22
Modern life depends on a reliable system for tracking time around the world. Without it, we wouldn’t be able to schedule international flights, time-stamp financial trades or coordinate military operations. Yet few people realize this precision relies on a single, meticulously maintained source — the time zone database, which Paul Eggert ’75 has voluntarily managed for the past 20 years.
Most people assume time zones are simple — fixed, logical, universal. Since 2005, Eggert, a computer scientist who teaches at UCLA, has coordintated the database and untangled a web of political disputes, historical inconsistencies, social customs and even leap seconds. It turns out time isn’t just measured — it’s negotiated.
Take Morocco, for example. Eggert explains: “Morocco wants tourists to enjoy a longer day, so they normally run their clocks an hour ahead of where the sun would put it. Kind of like permanent daylight saving time. But during Ramadan, they set the clocks back an hour, so people don’t have to wait as long to break their fast at sunset. We have to predict Ramadan each year and update the database accordingly. And since it follows the Islamic calendar, which is based on astronomical observations rather than fixed dates, the process isn’t as simple as just looking at a calendar.”
It turns out time isn’t just measured — it’s negotiated.
When Eggert arrived at Rice in the early 1970s, the university did not have a computer science department, so he majored in electrical engineering before heading to UCLA to pursue a Ph.D. in computer science. He taught at the University of California, Santa Barbara, for three years, before shifting to industry, co-founding multiple startups and working for System Development Corporation, one of the earliest software companies.
While doing business across multiple time zones, he noticed discrepancies in how different systems handled local time. At first, he tried to fix a few entries on his own, adding data for places like Taiwan and Indonesia. But the deeper he dug, the messier it became. “I thought, why don’t I just finish it off.”
That decision led him to the UCLA library, where he began piecing together the history of global timekeeping — sometimes from sources as unexpected as astrologer almanacs. In the early 1990s, he became involved in the time zone database, which was started by Arthur David Olson, an employee of the National Institutes of Health.
“People assume time zones just work,” Eggert says, “but making sure they do takes effort and a lot of untangling history.”
He’s had to solve countless historical mysteries hidden in timekeeping records. When did a country first adopt standard time? Did a war, revolution or political shift cause an abrupt change? Were old newspaper reports accurate or were officials simply guessing? In some cases, time zones weren’t even recorded, leaving him to piece together clues from legal documents, archived government memos and vintage train schedules.
Eggert credits Rice with giving students then — and now — a big-picture view of whatever problem set needs solving and “to use that to gain leverage on the details.” It’s an approach he’s used when working in the time zone database.
“That training helped me to see that I shouldn’t try to make the database do everything, because I could see the big picture right away and discover it before it was too late.”