There were some grumblings out of Russia recently with a governor of the eastern Primorye region ( Moscow + 7 hours ) suggesting that they 'cut' this to four hours to ease communication.

If they're going to fiddle around with things like that it would be best just to decouple entirely from the Mean Sun's schedule and adopt a universal time as you suggest.

Bizarrely all official communications and timetables in the Soviet Union were published in Moscow time, across eleven time zones. That made catching a local train in Siberia quite an arithmetic challenge.

Trains (at least long distance) in Russia still run on Moscow time.

"Run everything in Russia on Moscow time" is a localized version of "Run everything in the world on UTC". So the question is, how did it work, and should we port to that?

No, it's not, because you still had to do the math to figure out what time it would be.

This will not happen in the real world. There is simply no incentive big enough to make the whole world agree on this. Hell, we can't even agree to slightly reduce CO2 emissions.

Interestingly, though, China works on a single time zone. So for a small-scale case study in how this would work, go live in different parts of China for a year.

I find this a really good argument for it: how are you supposed to know if you call somebody in the middle of the night, if it's noon where you are, and the hour is the same? By having different time-zones, you need to look it up, but then you have an intuitive way of judging which stage of the day they are perceiving.

No, time-zones alone can't give you an estimate of sleep-times (even ignoring individual sleep patterns for the moment).

Time-zones are related to the longitude of the location You also need to account for the latitude, and the time of the year, because the pattern of day and night depends on all three factors.

You are complecting two problems: 1) When does the other person sleep. 2) What does his watch show.

Making 2) easier does not change anything with regard to 1).

For most people, their sleep is highly correlated with what their watches show.

It doesn't change the sleep patterns, but would you say it does not make a difference in judging at which hours other people sleep?

Yes, but who gets the better time spots? People are already pissed that time zones are based on England's time, how angry do you think they will be when they get some illogical time zone while the anglo-saxons get to keep the am in the morning and the pm in the actual afternoon?

I expect if we were all going to convert to UTC anyway, we'd also convert to 24h time while we were at it.

So, redesign all the clock watch-faces to be 24h instead of 12h too?

And replace the wristwatch of everyone who doesn't have a digital watch? And wall clocks?

Why redesign the watches? This problem doesn't exist in the places that use the 24h format (like most of the world around North America). We can use both time formats. I can either say 9 in the evening or 21 and everybody gets it.

Because "9 in the evening" doesn't mean much when you're a quarter of the world from GMT and forced to use GMT as your universal time.

Well, when someone asks me what time it is now, I don't say, "The minute hand of my watch is pointing at the 1, and the hour hand slightly past the 3." Instead I translate it to "three-oh-five". Wouldn't be too much of a stretch to say 15:05 instead.

(My point being that many watches and clocks already don't give us the literal time as it's spoken, just a representation.)

Edit: although just to be clear, I don't actually think we should switch to a single time zone. It would cause all kinds of headaches. I just think if in some universe it were to happen, it would necessarily go along with a switch to 24h time.

You can say 15:05 because you know it's the afternoon and so 3:05 translates to 15:05. Now think through how that works when the whole world is on a single timezone.

Yes, I agree that traveling would be hell with a single time zone regardless.

I would make a log every single day if humanity switched to a star date format.