The author is making it easy for himself with a contrived example with a key information already available.
> I want to call my Uncle Steve in Melbourne. What time is it there?
In a world with timezones, if your uncle is on the Internet and says "call me at 13h30" but doesn't tell you where he is, you can't call him, because you dont't know when is 13h30. (Think about that... he just gave you the time, but you still don't know the time...)
With timezones, you can't just give the time, you must also give a location. "Time" doesn't exist with timezones, only "time-location".
It's as if a physicist couldn't give you the mass of something without giving you the color.
"This table is 10kg-blue, which is the equivalent of 20kg-pink." (Because kg-colors aren't equal everywhere.)
On the other hand, with a universal time (UTC for example), 13h30 is the same for everyone, everywhere. The time can be given without any other information. If someone says call me at this number at 13h30, I can just do that without having to know where he is.
Let's look back at the initial problem:
> I want to call my Uncle Steve in Melbourne. What time is it there?
Well, if I have a universal time, it's very easy: it's the same time as where I am!
I don't even need to ask google! Beat ya!
But of course the author want to know if he can call someone out-of-the-blue by knowing where he is. Well, if you can use google to tell you what is the time in another timezone, you can use google to tell you what is the usual waking hour in this location. You don't need additional information in this example.
With universal time, the worst case scenario is needing the same amount of information as we do today (current time + location). The best case scenario is having a sane way of communicating time.
In both cases, you need a location to solve the types of problems humans want to solve. A hypothetical: is now an acceptable time to call a tech business in Asia from the US?
- With timezones: I need timezone (location). Generally I can call 9am to 5pm.
- Without timezones: I need location so I can figure out the range of times people typically work in that area (perhaps it might be 11pm to 7am).
And you're back to solving the same problem, just in a more complicated way with no helpful conventions.
In a world with timezones, if your uncle is on the Internet and says "call me at 13h30" but doesn't tell you where he is, you can't call him, because you dont't know when is 13h30.
Nobody who's used to communicating across timezones has this problem. After being bitten in the ass a few times you learn to say "Call me at 3pm eastern" or whatever. The no-timezones cure is way worse than the timezone disease.
> And you're back to solving the same problem, just in a more complicated way with no helpful conventions.
Not more complicated, exactly the same amount of complicated. You can add the conventions.
> After being bitten in the ass a few times you learn to say "Call me at 3pm eastern" or whatever.
And then you still screw it up because DST changes a week later in one country or another, or some such. Even when you do it frequently, it's not a solved problem by any means.
Not to mention, people have different times that are acceptable. And they travel. So at home I'll get up around 11am to 2pm, local time. When visiting SF, I'm usually up and about by 10am. I work with people all over the world, and they keep different enough schedules that I can't go by their location. And they travel, too.
So the author is right that in some weak contrived scenario, using a highly interruptive comm service, maybe zones help. Event they don't, cause Google could trivially give you the "apparent solar time" going by geography, anyways.
Timezones are an annoying hack. Daylight savings is even more obnoxious. Especially in poorly run counties that make up DST rules on an ad hoc basis.
In the context of programming, you should almost always be using UTC, maybe with an offset. Several times I've run into companies that keep call billing records in local time. Compete with extra hours and time traveling calls around DST jumps. Moronic. (And leap seconds can go get fucked, too. I'm saddened that we have to put up with such s pointless, annoying thing. Maybe we could switch to leap hours. No noticeable effect for millennia, at which point relativity should be a much larger issue with timekeeping.)
The author also doesn't help his case by pointing out the number of exceptions in using the existing system as a rule of thumb. Never mind 4am, what about calling someone at 4pm their time. That might be after the end of their working day in the Baltic states, or just after lunch in Spain.
Depending on location and specific business practices, 9:30am their time might be a good time to call in mid morning, but it might actually be the time they usually arrive at work, or in some Chinese cities the time they usually get out of bed. If it's 9:30 am on Friday it could be, like Europe, the last day of the week in some Muslim countries, the first day of the weekend in others, the only day of the weekend in Afghanistan, and subject to quite a bit of variety somewhere as full of Western run companies as Dubai. Most of these countries changed the days of their weekend in the last decade or so (which suggests problems with religious holidays are not insurmountable...). And that's the standard work week, without getting into the minefield of regional and religious holidays, and individuals' own holiday, sick leave and round-the-world travel...
Suddenly a universal status update system (or algorithmic handling of how inbound calls are passed on) looks far more necessary for the digital age than time zones.
The only thing in favour of time zones as a hack to assess someone's availability [given assumptions about their location] is their universal acceptance.
Scheduled calls are never miscalculated, no DST, no AM/PM mixups.
I hate timezones, and I especially hate switching times ie: DST. Having to work across timezones I have made these mistakes which were not only inconvenient, but screwed up my schedule for the rest of the day: Prepared for a call 6 hours early (oops I was supposed to add 3 hours, not subtract), missed a call (oops I was supposed to subtract 3 hours, not add), given a schedule that was 8AM, 8AM, 8AM, 8PM, 8AM, showed up 12 hours early for the 4th appointment.
Finally, I don't know if you realize this, but DST time is correlated with higher heart attack rates, increased traffic accidents, and a slew of other bad things.
If you're calling a specific person, you very likely know where they are. People don't move around that much. If he's not in his usual place, he's probably told you where he is if he's expecting a call from you. And even then, if it doesn't want to reveal or burden you with knowing where he is, we already have a universal time stanard he could use for this ("call me at 13:30 UTC").
Decoupling time-of-day for daily life from the position of the sun in the sky is the biggest over-reaction for the smallest barely-a-problem ever.
The author is making it easy for himself with a contrived example with a key information already available.
> I want to call my Uncle Steve in Melbourne. What time is it there?
In a world with timezones, if your uncle is on the Internet and says "call me at 13h30" but doesn't tell you where he is, you can't call him, because you dont't know when is 13h30. (Think about that... he just gave you the time, but you still don't know the time...)
With timezones, you can't just give the time, you must also give a location. "Time" doesn't exist with timezones, only "time-location".
It's as if a physicist couldn't give you the mass of something without giving you the color.
"This table is 10kg-blue, which is the equivalent of 20kg-pink." (Because kg-colors aren't equal everywhere.)
On the other hand, with a universal time (UTC for example), 13h30 is the same for everyone, everywhere. The time can be given without any other information. If someone says call me at this number at 13h30, I can just do that without having to know where he is.
Let's look back at the initial problem: > I want to call my Uncle Steve in Melbourne. What time is it there? Well, if I have a universal time, it's very easy: it's the same time as where I am! I don't even need to ask google! Beat ya!
But of course the author want to know if he can call someone out-of-the-blue by knowing where he is. Well, if you can use google to tell you what is the time in another timezone, you can use google to tell you what is the usual waking hour in this location. You don't need additional information in this example.
With universal time, the worst case scenario is needing the same amount of information as we do today (current time + location). The best case scenario is having a sane way of communicating time.