Discussion of time zones and how they should work is hotter than ever right now. I think it’s great. Systemic change is a hard and increasingly uncommon thing, even if seemingly everyone agrees that it would be a great.

So yes, things that appear fundamental to modern life, like daylight savings time, are still worthy of inspection. Are they still useful to us? Do they make life and the systems we build simpler or more complicated?

Time zones were born out of technology. Before mass communication and rapid transportation, every place could observe time at its own convenience. Noon is when the sun is highest in the sky. Set your pocketwatch to the clock in the town square when your weeks-long transatlantic voyage is over and move on with your life. Eventually, people started to care that the trains were on time, and now, nearly two hundred years later, we have to re-learn how to set the time on our ovens and microwaves every six months.

Today, time zones are a complex mess. The world seems to generally agree that we want it to be daytime when the sun is out. In practice, time zones are largely motivated by political, economic, and social pressures.

Thanks to Heitordp on Wikipedia.

Technology has progressed quite a bit since the mid-1800s when time zones were first implemented. We have computers now, and those computers have GPS. No longer do we have to force wide swaths to compromise on what time it is. Instead of simplifying time zones slightly, why not remove them altogether? What if there were no time zones? Or, if you prefer, what if there were infinitely many time zones across the continous range of longitudes?

Let’s say that we keep UTC and the convenient Prime Meridian running through Greenwich in England. This currently serves as the anchor relative to which all time zones are defined. We can calculate a simple “natural” time for any given location given its longitude. Conveniently, both longitude and time are centered at the Prime Meridian: 0° and UTC+0.

There are 360° of longitude, ranging from 180°W to 180°E (or -180° to 180°). If the Earth rotates once every 24 hours (a simplification, but close enough), each of these degrees of longitude corresponds to four minutes of UTC offset. With this information, we can easily find the infinitely-many time zone time of any point on Earth. Unsurprisingly, this would change things quite a bit.

If you’re like me, your personal time is defined almost entirely by your phone, which is already location-aware. When I drive between time zones, the time silently updates and I think nothing of it. By removing formal time zones, the resolution of these updates increases infinitely — with every miniscule change in longitude, my phone’s time updates imperceptibly.

For example, if I’m driving eastbound on US-50 toward Newton, Kansas at about 55 miles per hour, the clock on my phone (or the GPS-connected clock in my car) would advance 16 minutes for every 15 minutes I’ve driven. Heading the opposite direction, I’d see the opposite effect: a 14 minute difference in clock time after 15 minutes of driving. If, in this scenario, I’m on my way to a 9:00am appointment an hour away, I’d have to leave at 7:56am if my destination is to the East, but I could leave as late as 8:04am if I’m headed West.

Modern technology enables scenarios where precise timing is important. In typical daily life, you probably wouldn’t have to think about this too much. Not only would navigation apps compensate for the time difference between your origin and destinaton, but the socially accepted margin of error for being on time could soak up a 90-second error in arrival.

Currently, the entirety of China shares a single time zone. Noon in the country’s Western extreme, near the border with Tajikistan, is also Noon at the Eastern extreme, near the border with Russia in Siberia, over three thousand miles away. Without the tyranny of time zones, each location can enjoy its natural time, separated by more than four hours.

On a smaller scale, if the time at the end of the Santa Monica Pier is about 2:30pm (UTC-07:53:59.96), the time at Home Plate at Dodger Stadium is advanced by more than a minute and is 2:31pm (UTC-07:52:57.66). If you’re planning to watch a baseball game from the beach, your device would compensate for the 62-second time difference so you don’t miss the first pitch.

Some small time zone-like constructs would probably be necessary. We’d need time coordination across large complexes like Denver International Airport for example, where the start of Runway 7 and Runway 36 are separated by about 34 seconds. For convenience, they might say that all airport operations are coordinated at a central location, like the time at the control tower at the airport’s center.

Use the interactive map below to check the current natural time and UTC offset of different locations in your life. What would your life look like in a world without time zones?