1. Seconds in one time system last the same amount of time as seconds in another time system
2. Seconds in the same time system last the same amount of time as each other
3. Time numbers are strictly increasing - the same time number can't happen again
4. [etc, kill me]
That's part of the genius of Leslie Lamport, embracing the fact that your distributed clocks aren't consistent, so start looking at effects through distributed systems from a light cone perspective just like you do with relativity.
We should also define the length of a second to mean "at sea level in Greenwich".
The quest to eliminate irreproducibility from metrication is why SI did all that work to finally eliminate the kilogram prototype. The second was defined reproducibly decades ago because trying to define it based on our planet's inconstant spin was such a failure.
The fact that the Earth's spin is not constant is perhaps frustrating, but like other facts just insisting it isn't true doesn't help you.
But the size of the discrepancy between Colorado and London is far smaller than the discrepancy Leap Seconds are concerned with right?
Why would it? My redefinition just means the length of a second is defined as a given number of cycles of caesium in a gravitational field equivalent to that of Greenwich.
If you're in a different gravitational field, you'll just have to convert the values easily.
> Tidal datums must be updated at least every 20-25 years due to global sea level rise. Some stations are more frequently updated due to high relative sea level trends.
If we are going so far as to rigidly include "sea level" in the definition of "a second", it would probably help if we say that that we mean mean sea level.
Know what I mean?
That's why I proposed changing the second definition to 9192631770 cycles in a gravitational field equivalent to that of Greenwich.
So at the end of the day it doesn't matter if it's in 'error' or a fundamental to the physics even under perfect conditions. Neither are really under your control and both have the same answer.
> You can't escape answering the question: do I care about the time elapsed at home or the time elapsed here?
We already have that concept, in the difference between CLOCK_WALL and CLOCK_MONOTONIC. You use monotonic for "local temporal reference frame" and wall for "proxy of globally visible temporal reference frame". Wall shifts around anyway as NTP or what have you figures out how skewed off of "actual" time you are.
Yes you can. When error swamps the difference between two things, you don't have to choose.
Do you set your analog alarm clock to wake you at 6:00:00 or 6:00:05?
Anyone on Earth can just say their computer clocks are set to "Earth", ignore relativity, and use their normal clock skew correction algorithms.
It's not "You can't escape answering the question". It's "Interplanetary spacemen can't escape answering the question." And those spacemen might not even use seconds.
HN discussion (among others less recent and/or less popular): https://news.ycombinator.com/item?id=19922062
More falsehoods: https://infiniteundo.com/post/25509354022/more-falsehoods-pr...
Instead have 2 calendars: the normal date time is standardised, no leap anything and simply increases. The orbital time tracks the earths revolution around the sun.
Sure, eventually the two will drift. But leap days account for 3 weeks-ish of time for the average person through out their life (let’s assume 80 years life span for arguments sake). So this doesn’t seem so hard to adjust to.
In my system, the time is simply a number that increments. No calculations are ever needed to correct anything. This is what most people use to schedule things.
The second "clock" tracks position of the earth around the sun. You need it for the seasons. But this too is always exact. There will never be a situation where we need to adjust it. You can never reach the end of a year and be slightly short on the distance traveled around the sun. So one day Xmas is slightly warming than usual. But so what?
But the real magic of the calendar is that billions of individuals use the same calendar for the same problem and thus we can all agree what day it is, every single day.
So if there's an issue with the existing calendar, then simply adjusting our calendar by an amount really no-one will notice is by far the most practical solution. Almost every industry cycles with the season; we need the calendar to track it accurately.
The article is all about trying to get 2 things to sync because of the slowing down of the earths rotation. You haven't actually described why we need to go to this effort beyond maintaining the current system. Nor why this is a practical thing to do in general beyond maintaining the current system.
Loads of people accept weird times shifts all the time. The poles have 6 month days and nights. In the summer I get 3 extra hours of day light and treat 7pm as "day". We already adjust what we do by what it looks like outside. Why does the time need to "match"?
Keeping the time in sync with the orbit of the earth isn't just about the "here and now" but also history.
If our calendar is off by a second or two a year, it's very easy to correct without confusing the general populace - most people want to spend precisely zero time thinking about calendars and orbits. Currently, only a few nerds have to worry about leap seconds and the like. And it's part of their jobs, so it's OK.
In a two-calendar system, every human will have to keep track of a personal calendar and a scientific calendar. Asking people who don't care to do that - and to fix an issue we already have an almost zero-friction fix for - is a non-starter.
I suspect the real reason my be overlapping domains of varying precision/accuracy, which tolerate different degrees of error on any specific time measurement, but still need to agree on a shared center of the distribution of that error.
So in our daily lives, we might tolerate a fraction of a second of drift without notice... But there are some specialty domains that do require more precision, and we need the time measurements in both domains to mostly line up, to avoid confusion. So our daily clock needs to be slaved to the more precise clock, even if we don't require that precision in most things.
But we do all sort of dumb time related things: - day light savings - leap seconds, days, years
Some places too close to the poles don't have normal day/night cycles of light. So we already tolerate a lot of weird time stuff. This way we keep tolerating it and get rid of the calculations.
https://wiki.lesswrong.com/wiki/Chesterton%27s_Fence
You need to learn the actual reasons why precision synchronous time exists. Until you do that, you're just wandering around in the dark, being silly.
Measurement systems ultimately serve the needs of those who are doing the measuring. This fact alone accounts for many of the idiosyncratic aspects of traditional measurement systems. An acre-foot measurement (a volume of water) makes sense when you've got a pond whose surface area (in acres) is known, and whose depth (in feet) can be measured against a post or dam face. An acre itself is the amount of land a farmer can plough in a day (in German, Tagwerke), and would vary by terrain, farmer, plough, draught animals, and hitches.
Time systems suitable for other needs may come to be used. So long as a substantial human population remains on Earth, an Earth-centric time system will all but certainly exist, and adapt to changes in the Earth-Moon-Sun system's orbital and rvolutionary characteristics.
...aaaand there's an xkcd: