I was wondering the other day why countries still use non-standardized measurements for everything from weight to distance to currency, while the 24-hour clock exists across the board. The result of my hour on the internet is vague and complicated and I'm not even totally clear on if there's a "real" answer, BUT! here are a couple of things:
1. Humans seem partial to multiples of 6 when it comes to daily timekeeping, which seems helpful when standardizing time because everyone is pretty much on the same page. (I wish I could find more of these--Daniel was looking them up on his phone the other night, and he's not here, so you just get what I've got open in my tabs.)
"The weekday of a Hindu calendar has been symmetrically divided into 60 ghatika (= 24 hours), each ghatika is divided into 60 pala (= 24 minutes), each pala is subdivided into 60 vipala (= 24 seconds), and so on."
The traditional Chinese time system, called shi-ke, split the day into twelve "milestones," each two hours long.
2. That said, some Chinese time systems were in decimal time: "Several of the roughly 50 Chinese calendars also divided each ke into 100 fen...In 1280, the Shoushi (Season Granting) calendar further subdivided each fen into 100 miao, creating a complete decimal time system of 100 ke, 100 fen and 100 miao."
The French tried to make decimal time a standard thing after the French Revolution out of a desire to reject the Gregorian calendar, and because measuring in multiples of 10 was a very Enlightened (and metric) thing to do.* I'm guessing it didn't take off because very few groups defaulted to decimal time.
In 1998, re: decimal time, a watch company tried to make "internet time" happen.
3. A cool hypothesis about why the whole world (essentially--I'm sure there are some outliers) is time-synced is Railway Time. We had to have consistent methods of telling time or trains would constantly hit each other.
4. I then stumbled onto Planck Time (aside about how Max Planck is so cool, ugh), which led me to chronons and attoseconds, which led me to Orders of Magnitude (Time) in general, and then my brain exploded because a yottasecond IS A THING.
5. I also happened upon this during my Planck Time jaunt: "The speed of light in a vacuum provides a convenient universal relationship between distance and time, so in physics (particularly in quantum physics) and often in chemistry, a jiffy is defined as the time taken for light to travel some specified distance." So now you know how long a jiffy is (actually, it can denote like five different time measurements, but they are all very fast).
I'm often hesitant to post things like this because they aren't really research so much as interested perusals, but I don't think anyone will suffer from my lack of rigorous scholarship. Ok, just gonna post this and not downtalk myself. Exposure therapy!