But even with fewer time variations, time confusion again arose as a problem in the 20th century. The advent of air travel compressed distances even more, and the rise of the internet and mobile devices enabled instantaneous communication between people all over the planet and gave us a 24-7 culture in which we're tightly interconnected to events in distant places.
That's why a few years ago, Hanke and his colleague, Johns Hopkins University professor of physics and astronomy Richard Conn Henry, proposed an even simpler solution. They want to do away with time zones completely, and put the entire world on universal time (UTC). Under their system, when it's 9:00 in one place, it's 9:00 everywhere on the planet, even if it's morning in one place and evening in another.
In addition to making it easier to adjust to travel, having one time across the planet would make it easier for people who need to, say, set up conference calls with groups of individuals scattered from Montana to Germany, as Hanke, who is supervisory board chairman of a Dutch company, sometimes has to do.
"Endless confusion would be gone forever," Henry concurs in an email. "Life will be simpler!"
Abolishing time zones might also eliminate the negative health effects from sleep deprivation that affect people who live on the western edge of time zones, as described in this May 2019 article in the Journal of Health Economics.
Since Hanke and Henry proposed abolishing time zones in 2012, others, such as bestselling author and New York Times essayist James Gleick, have supported the idea as well. And to a certain extent, a switch to universal time already has taken place. Pilots and air-traffic controllers in the U.S., for example, rely on universal time (or "zulu time, " as they call it). Financial traders, whose dealings sometimes cross borders as well as time zones, stamp transactions in universal time as well, to make sure that the pricing is correct. And the internet essentially runs on universal time.
Some might wonder if a switch to universal time would alter the rhythm of people's daily schedules, but Hanke doesn't think so.
"People say, 'Oh, if we went universal time, that would mean we'd have be opening businesses when it's dark outside.' No, your business would go like it does now, with the sun. In New York or Baltimore, if you open normally at 9 a.m., that would be 14:00 [2 p.m.] on your watch," he says (assuming GMT is 9 a.m.) It might take some getting used to, but Hanke thinks that in a generation, children who grew up with UTC would no longer associate, say 7 a.m. with breakfast time or 9 a.m. with starting work. And the switch not unheard of.
"China currently has this 'problem' in that it has one time zone for a huge swath of East-West real estate," Henry adds. "But it is totally cured by having local decisions as to opening/closing times for businesses and so on. That would obviously be essential for a world-wide system."