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Atomic Clocks

nist.gov

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Re: Atomic Clocks

#11

Post by NitpickLawyer »

mullingitover wrote: post #8
r3trohack3r wrote: post #4

> Today’s best atomic clocks are billions of times more accurate and precise than any other type of clock. If they had been running since the Big Bang, 13.8 billion years ago, they would have lost or gained less than a second. Absolutely incredible, but then confused by the next assertion that is made without context: > New kinds of clocks may soon open up capabilities that previous generations could only dream about…

Pretty sure you can rig something far better than radar if you have the ability to detect extremely tiny gravitational waves via an array of hyper-accurate clocks.

> detect extremely tiny gravitational waves via an array of hyper-accurate clocks.

I wonder how tiny is feasible. Would it get to a level of accuracy where you could detect neutrinos? We know they have some (v tiny) mass, so it should in theory be detectable that way?

Re: Atomic Clocks

#12

Post by gucci-on-fleek »

isolli wrote: post #7
r3trohack3r wrote: post #4

> Today’s best atomic clocks are billions of times more accurate and precise than any other type of clock. If they had been running since the Big Bang, 13.8 billion years ago, they would have lost or gained less than a second. Absolutely incredible, but then confused by the next assertion that is made without context: > New kinds of clocks may soon open up capabilities that previous generations could only dream about…

What are these atomic clocks measured against?

I think that they typically use lots of other atomic clocks [0].

[0]: https://en.wikipedia.org/wiki/International_Atomic_Time

Re: Atomic Clocks

#13

Post by Schlagbohrer »

NIST is a great example of a true Public Good.

Also, has anyone else ever used their Randomness Beacon? I once used it to settle an argument in a book club over which book to read next. It's basically a very fancy and high tech coin flip.

https://csrc.nist.gov/projects/interoperable-randomness-beac...

Re: Atomic Clocks

#14

Post by seanhunter »

r3trohack3r wrote: post #4

> Today’s best atomic clocks are billions of times more accurate and precise than any other type of clock. If they had been running since the Big Bang, 13.8 billion years ago, they would have lost or gained less than a second. Absolutely incredible, but then confused by the next assertion that is made without context: > New kinds of clocks may soon open up capabilities that previous generations could only dream about…

> What dreamy capabilities do we get that we don’t enjoy today?

The next gen will have an alarm with snooze button.

Re: Atomic Clocks

#15

Post by tomcam »

Long before most of you were born there was a special number you could call to get the time here in the USA. It would give you a localized time every 10 seconds. It was considered an authoritative value, but I knew that normal analog clocks drifted a fair amount, and I was fascinated by the Time voice.

There was also a special number to dial that was called Information. When I was about 12, I suddenly thought that’s amazing, you can just call and get information. What I didn’t know at the time was that it only applied to phone numbers.

One day, I called Information and asked them how accurate the time number was and what mechanism was used to deliver it. Incredibly, they connected my preadolescent self to a public relations person at AT&T. That person somehow took me seriously and hooked me up with another party. And that person told me about the cesium atomic clock used to keep track of the time.

Later, I would call Information to find out the acreage occupied by the Los Angeles Zoo, and it was then that they brusquely explained to me that the number was not for general knowledge.

Re: Atomic Clocks

#17

Post by firasd »

What, Exactly, Is a Clock? To understand atomic time, we must first understand something about clocks.

A clock is, at its core, a marriage of two components: a mechanism that oscillates, or ticks with a steady beat, and a device that counts those beats and displays the time

Yeah but more deeply time is a property of the universe that the clock including atomic clocks are tracking. Kant said it is 'schema' i.e. without understanding time we wouldn't even understand causality so it is the purest possible a-priori concept that doesn't rely on sensory input to learn about

This is why I like using my Alphadec system that splits the year into 26 chunks from A-Z https://github.com/firasd/alphadec> as my working dir; eg. right now the current Alphadec is '2026_P5M7_200286' so my working dir is Documents/work/2026_P. That way there is a folder system automatically imposed on various .js or .py stuff without having to pre-create a taxonomy since 'time is schema'--I can estimate "that ffmpeg project was in Spring so it must be around 2026_F.."

Re: Atomic Clocks

#18

Post by benterris »

firasd wrote: post #17

What, Exactly, Is a Clock? To understand atomic time, we must first understand something about clocks. A clock is, at its core, a marriage of two components: a mechanism that oscillates, or ticks with a steady beat, and a device that counts those beats and displays the time Yeah but more deeply time is a property of the universe that the clock including atomic clocks are tracking. Kant said it is 'schema' i.e. withou…

Not sure I get what is better about this than simply using the month, like Documents/work/202606 (which also sorts nicely and does not need a conversion in my head to know what time of the year that must be)

Re: Atomic Clocks

#19

Post by firasd »

benterris wrote: post #18
firasd wrote: post #17

What, Exactly, Is a Clock? To understand atomic time, we must first understand something about clocks. A clock is, at its core, a marriage of two components: a mechanism that oscillates, or ticks with a steady beat, and a device that counts those beats and displays the time Yeah but more deeply time is a property of the universe that the clock including atomic clocks are tracking. Kant said it is 'schema' i.e. withou…

Not sure I get what is better about this than simply using the month, like Documents/work/202606 (which also sorts nicely and does not need a conversion in my head to know what time of the year that must be)

Yup as far as the folder taxonomy thing ISO YYYYMM works fine too

Alphadec is just a timezone free UTC encoding that works down the millisecond so I also use it for snapshots eg

  myscript.py.backup.2026_P5G6_328054_Aug06.txt
So then when I'm doing multiple revisions I don't have to worry about which revision of 20260806's day it was etc. Unix time in ms would work too but Alphadec is a little bit nicer to me than saying myscript.py.backup.1786086462604.txt

Re: Atomic Clocks

#20

Post by OuterVale »

tomcam wrote: post #15

Long before most of you were born there was a special number you could call to get the time here in the USA. It would give you a localized time every 10 seconds. It was considered an authoritative value, but I knew that normal analog clocks drifted a fair amount, and I was fascinated by the Time voice. There was also a special number to dial that was called Information. When I was about 12, I suddenly thought that’s…

Here in Australia we had a number that gave you the time called 'George the talking clock'.

https://1194online.com

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