Zero point leet seconds (2018) | Hacker News Reader

Zero point leet seconds (2018)

susam.net

129 pointssusam38 comments

Remember, the speed of light in fiber optic cables is ~1.47x slower than its speed in a vacuum, which means an equatorial transit is 0.2s instead. This difference is significant enough that some High Frequency Trading firms have used microwave links to reduce latency from Chicago to New York from 7.5ms to 5ms. https://arstechnica.com/information-technology/2016/11/priva...

Well. Significantly more than that due to latency from switches etc and also because of the fact that there's so little land along the equator, meaning there's only one cable that travels roughly equatorially. It's from Fortaleza, Brazil to Kribi, Cameroon: https://www.submarinecablemap.com/

If you set up a bunch of good first-surface mirrors, I'm pretty sure you could get to pretty much the speed of light. You'd have to put them pretty high up in the air to avoid hitting things (a problem for cables as well, obviously) but putting the beam 2km in the air would still only lengthen the path by 4pi km, or .03%.

I have always found it very neat that the propagation speed of a light wave in glass is roughly the same as electrical waves in a coaxial cable. Both are shockingly slow compared to air/vacuum, but for completely different reasons. In both cases the advantages in signal integrity are immense.

Discussed just 1 month ago:

https://news.ycombinator.com/item?id=33110478 (175 points, 162 comments)

They're both light waves, and it's for the same reasons (the medium/waveguide stores and releases energy).

one would usually consider a waveguide and a medium to be very different, but good job! You've managed to be condescending while also remaining completely opaque to anyone who does not already completely understand both cases.

As the manager of a vulnerability research team, I almost always organise my team's meetings to start at 13:37. It's become customary for us to refer to it as "leet o'clock".

Leet o’clock is my favourite time of the day. It also just so happens that right now as I am typing this the current time in my time zone is 13:37 :D

Edit: the time changed to 13:38 just before I hit submit :(

Similar to "the game"[0] (you all just lost), for many years in a group of friends we'd text each other "leet" at 13:37 whenever we'd notice and whoever did it first won that day. Obvious gentleman's agreement to not just use an alarm clock and notice it naturally during the course of the day. Have been doing it for about 20 years now with one of them that kept it up.

[0] https://en.m.wikipedia.org/wiki/The_Game_(mind_game)

I'm shocked that you do this to be honest, because I have my friends and I also do this. I didn't realize that we weren't alone. Not that I thought we were special, moreso that we didn't think anyone else would want to do something so silly.

The other explanation is that you two are friends who don't know each other's usernames

Looks from the profile the other user is from Canada and I was referring to a friend group from childhood in Portugal, none of which are in Canada nowadays. I think we're just not so special :)

Used to be common on IRC as well.

I am born at leet o'clock. Usually I say 13:40 for rounding reasons and before today I never thought about it this way, even though I am familiar with leet speak. But from this day on I'll be proud of my birth time, no more rounding.

I'm qurious when you would say your birthtime? I don't even know mine.

Many cultures care about it for astrology reasons.

I only learned it when I got married and had to hand in a copy of my entry in the birth registry.

Missed leet time by one minute though...

In our working group (astrophysics) leet o clock is the traditional time for cake.

Erm, there is a superstition in my region/country that say that you're sleepy at your birth time. So when I was in school, and I had hours at school until 2 PM (6 hours from 8 AM to 2 PM) and I was sleepy around that time then my mother revealed to me that I was born at 13:37, so that's how I know. And you know how parents are, they like to repeat some stuff throughout your life, like it or not. So I got drilled in my head what my birth hour:minute is.

Good thing are only 60 seconds in a minute other wise the 8:00:85 "boobs o'clock" morning meeting would be awkward.

Just add some emphasis and start right at 8:00:00.85.

When do people eat? I presume not from 13 to 14.

Also, how long do the meetings last? If you're serious, it's a nice gimmick but terrible for actual time management.

They're quite short meetings, typically less than 22.284 minutes apiece.

.284?

Should be .2833333 1337 seconds

L33t o'clock has been a thing for me for years now. I experience that weird phenomenon where you look at a clock and it happens to be 11:11, except for me it's 13:37 and I'm like "hey, it's l33t o'clock!"

There's another one I call "Razor o'clock" at 7:11 pm, i.e., 19:11.

That stands out because when you look at the clock and it's something uninteresting, you just forget about it.

I had no idea that I needed to know that, but now I don't know how I could live without it.

I’m not sure that’s worth remembering specifically. You should really already roughly know the Earth’s circumference, 40k km, and the speed of light, 300k km/s. 40/300 = 4/30 = (4/3)/10 = (1.33)/10 = 0.133.

https://xkcd.com/1053/

Which is not as fun as 0.leet: knowing that there's a 0.leet is good trivia, and no trivia is "worth" remembering... you just remember it because it's interesting and fun =)

Yep. I say that because I was very recently looking into the network latency for computers on the other side of the world. I ran the same theoretical calculation of circumference of the earth divided by the speed of light and measured ping times and they lined up quite well. Now, to be clear, OP definitely has one up on me because I didn't notice the 1337, but it stuck in my head that to one significant digit it's ~100 milliseconds to get around the world. Now four significant digits stick in my head. Thanks OP!

You can't go faster than leet.

If I get nothing else done today, I will at least have learned this cool fact/number.

Flew Newark to Portland on UA 1337 the other day. If only that flight took 0.1337 sec...

This proves that Earth is a truly leet planet.

And flat (with edge-wrapping)? For light to go 'around' the world--it travels in a straight line.

Ok, so it proves that Earth is a black hole with the equator on the event horizon.

This proves there must be a god.

And this is why I come to HN

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