The imaginary line has to go somewhere. π€·
this post was submitted on 20 Nov 2024
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I talked to a guy that thinks we should just all use Unix Epoch on here once. We'd still need local informal systems to describe the time of day and weekday, but the more I've thought about it the less stupid it sounds. Date/time systems are a pain in the ass and necessarily ugly.
Shit programmers say...
The problems of time zones only affect a handful of people, the wast majority of people nearly never think about this.
Epoch or standard time would just rename time zones, beucause currently you say hour offset from London, with "no timezone" you would have to say something like, noon is at 05:00 utc/epoch at that city, so nothing really changed
Industries where it actually matters already use UTC for everything, e.g. international flights.
It would make more sense to switch to base 10 minutes and hours than to "solve" the time zones
Yeah, I'm not seriously suggesting this is something we should get on, lol. Maybe solve world hunger or just all the wars first before another radical standards reform.
The difference would be that you would actually just schedule something for a megasecond out, instead of having to screw with timezones or reference the sun at all. It wouldn't matter much locally, but for anything international - like probably this conversation - it would be easier. Even UTC has hard edges.
If we seriously go into space it's going to be really picking weird thinking in terms of the incommensurable days and years of a distant planet, at which a point it might not be just a trivial issue anymore.
Would you redefine the second to make your decimal system work? We'll need a new Epoch system then, haha. The French did try to do something like that.
What would be easier with our conversation? I guess we are at the other side of the globe. I wasn't answering because I was sleeping, you won't answer immediately because you are sleeping, what would help if our clocked showed the same? Both of us sleep because the sun is down, not because the clock says something.
With long range space travel we will have to deal with the relativity of time as well. Lets say we define an Epoch and both of us do something exactly a googol second later but we live on a different planet, it wouldn't be at the same time because of relativity. If I would say lets do something when it is 12:00 in London, UK, Earth, than you can convert it to your relativity and time zone.
About the intetplanetary usage of the current system, it's already in effect, LTC aka Coordinated Lunar Time is already under development since this April.
On the moon, a smaller body where the gravitational pull is much weaker, time moves more quickly and unevenly: Lunar time gains about 58.7 microseconds per day compared to Earthβs time, though even this can vary, depending on the altitude and longitude where lunar clocks may be located.
βAn atomic clock on the moon will tick at a different rate than a clock on Earth,β Kevin Coggins, manager of NASAβs Space Communications and Navigation Program, tells the Guardianβs Diana Ramirez-Simon. βIt makes sense that when you go to another body, like the moon or Mars, that each one gets its own heartbeat.β
So the solution is to just convert between time zones, and resync them sometime because they can drift because of relativity.
I don't know how a base 10 day would work, it just annoys me that its reform wasn't successful with the metric system. But I don't know how it will work when people will live on Mars. A day on Mars aka a Sol is 24 hours and 39 mins. Will they have "Mars hour" which equals 1 Earth hour and 1.6 Earth minutes? If not, they could simply use Earth hours, than it won't be possible to create classic circular clocks.
The conversation is easier because we have a shared understanding of the time.
When you ask me can you call me at 13:00, I currently need to google what your timezone is and convert it to my timezone to know whether my sun is up.
If instead I just know when my sun comes up and goes down in UTC, I can immediately answer if I'm available at 13:00
Relativity does make space more difficult, but we'll ultimately have to make some shared reference point there, too, as you've pointed out
But I have to google when the sun comes up for you, it's literally the same thing.
In the context of I'm not available and you need to know when to call, sure
In the context of we're currently talking and trying to plan when we'll talk again, UTC is infinitely easier once you have 5 different people talking
Yeah, you can use an hour/day-based system elsewhere, but it's goofy and has a lot of complications. If a separate culture were to grow up on the moon, they would start to wonder why their measurements are based on the particular natural rhythms of a place they've never been, except eventually out of sync completely.
We haven't actually scheduled anything here, but if we were to I'd default to UTC like you said. The thing is, it's just not as simple as a decimal count, and it has leap seconds, and there's daylight savings and permanently changing timezones and physical relativity that can make it difficult to know what your current offset is. If we were to drop the requirement that the time has anything to do with the day/night cycle and the seasons, all that goes away.
The current system is definitely good enough, but it could be done better.
What's 12h/15h? How long a day is?
At 00:00 (midnight) UTC on monday, Russia's time would be 12:00 (noon) of monday and alaska's would be 15:00 (3 pm) of sunday.
Local time
What's the h for?
Hour. Just a weird way to say 12:00 and 15:00 or 3pm and whatever 12:00 is in am/pm talk
12am is midnight and 12pm is noon. But most people just say "noon" or "midnight" because it's less confusing.
That is confusing. "PM" is "post meridian" or, as I understand it, after the middle. One would think it wouldn't be PM until 12:01 or at least 12:00:01.
Which is why I, as you said, use "noon" and "midnight."
If you look at https://en.m.wikipedia.org/wiki/12-hour_clock#Confusion_at_noon_and_midnight it's also not at all clear if 12:00 am is midnight or noon.
To me the clock jumping from 11:59 am to 12:00 pm and then again from 12:59 pm to 1:00 pm seems weird. Imho, stepping from 11:59 am to 12:00 am and from 12:59 am to 1:00 pm would be more logical.
Didn't expect this almost a month later.
I agree with probably 50% of your post. I agree that it's not clear whether 12:00am is midnight or noon. However, if you recognize noon as the meridian, 12:00:01 is post meridian, i.e. after the middle (presuming that 12:00:00 was the meridian). It becomes after the middle immediately after the middle, not an hour later.
I don't mean to be contrarian, but that's not the part that confuses me personally. Really I think the world should just convert to 24 hour time.
Didn't expect this almost a month later.
Sorry, I just discovered this community and didn't look at the date.
Really I think the world should just convert to 24 hour time.
Definitely. In Germany, we often use the 12 hour system in spoken language, but always with an indication (morning, noon, afternoon, evening, night) unless it's already clear from the context. But in written language, using the 24h system is most common.
No need to apologize! I was expressing surprise, not displeasure.
In the USA, as I'm assuming you know due to your clear fluency in the language, we largely rely on context but add am/pm if necessary. Most of the time when I personally discuss times, it's for an appointment or meeting, and most of my 12:30 meetings aren't happening thirty minutes after midnight (the ones that do aren't usually scheduled in advance). We've managed so far, but there are for sure better approaches.
I would like to reiterate that I wasn't criticizing, just observing. My search engine says it's 8am in Germany, so hopefully you're having a great morning!
I didn't feel your reply as critics too. I also wish you have a great time, whatever time your clock might currently show.
Just shy of 3am.
I can never remember it properly either but when someone reminds me (thanks samus12345) which way around it is it does kind of make sense.
If you think of 12:00 as literally an infinitesimal slice of time it's not really possible to give it an am/pm distinction, as it is literally the devider between the two. BUT, in a more real-life approach 12:00 is probably not an infinitesimal slice of time but the minute after a digital clock flipped to 12:00. That can be 12:00:00.00004 or 12:00:30 or 12:00:59.999944. And all those are indisputably pm.
Couldn't it be 00:00 PM? So zero time since meridian?
That's not a bad suggestion, but may interfere with 24 hour clocks.
That's why you switch the clocks over to 24 hours
I can't tell if you're agreeing or arguing with me.
Correct - technically, noon is neither am nor pm, but clocks and the like have to have SOMETHING there, so am for midnight and pm for noon was arbitrarily chosen.
hydrogen
Hour, it's noon Monday on the Russian side and 3pm Sunday on the American side.
So Sarah Palin can see into the future!?