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Grace Hopper on nanoseconds

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Re: Grace Hopper on nanoseconds

#31

Post by shabble »

I can't view the video, so I'm not sure if it's straight up transcription error, or just confusion, but:

the length of wire that is as long as light can travel in one nanosecond. The length is a very portable 11.8 inches. A microseconds worth of wire is a still portable, but a much bulkier 984 feet.

Understanding the profligate ways of programmers, she suggests that every programmer wear a necklace of a microseconds worth of wire

(Emph mine) I can see ~12" as a perfectly reasonable necklace length, but ~100 yards? Seems like a bit of a pain in the neck.

[Edit:] After a bit of playing around with Wolfram Alpha, it seems that a microsecond of AWG#40 copper would weigh only ~14 grams. But at 0.08mm, or around half the thickness of a hair, it's going to be a bit fragile.

Using a more reasonable #28 (0.3mm) wire comes in at 220g, which is definitely on the high side for a necklace.

And woe betide anyone using gold!

Re: Grace Hopper on nanoseconds

#32

Post by moreati »

shabble wrote: post #31

I can't view the video, so I'm not sure if it's straight up transcription error, or just confusion, but: the length of wire that is as long as light can travel in one nanosecond. The length is a very portable 11.8 inches. A microseconds worth of wire is a still portable, but a much bulkier 984 feet. Understanding the profligate ways of programmers, she suggests that every programmer wear a necklace of a microseconds…

> but ~100 yards? Seems like a bit of a pain in the neck.

That's the point - to serve as a constant reminder of how much circuit/processor time is thrown away for every microsecond it sits just waiting

Re: Grace Hopper on nanoseconds

#33

Post by Someone »

lutorm wrote: post #10
tripzilch wrote: post #9

That first paragraph was as good as unreadable thanks to all the miles, gallons and Fahrenheits. 11.8 inch ... times about 2.5 is umm wait it's a link, maybe if I hover it, no they didn't put metric in the title tags either. "In one millisecond, light travels 186 miles", which is about the same distance as a million squirrels put head-to-toe. Why not measure in squirrels? It makes about the same amount of sense, exce…

I don't endorse inches as a measure, but they are pretty intuitive. Maybe it's because the swedish word for inch is "tum", which means "thumb". And it happens to be 1.25 inches from the top of my thumb to the first joint.

An inch is (supposedly) measured as the _width_ of the upper phalange of the thumb, not as its length.

And 'thumb' is its name in Dutch and French, too.

Re: Grace Hopper on nanoseconds

#34

Post by phaus »

enneff wrote: post #30
phaus wrote: post #21

So far you guys have overlooked what was possibly her greatest contribution to humanity. She was credited with coining the phrase "It is better to ask for forgiveness than to ask for permission." In all seriousness, she was an amazing person. Whenever I hear someone start complaining that women shouldn't be allowed to pursue a career, I think of all of the things that we wouldn't have if it weren't for women like Gra…

> Whenever I hear someone start complaining that women shouldn't be allowed to pursue a career... Woah, where do you hear that?! Aren't we in 2012?

"The radical feminists succeeded in undermining the traditional family and convincing women that professional accomplishments are the key to happiness,"

-Rick Santorum

Re: Grace Hopper on nanoseconds

#35

Post by lutorm »

Someone wrote: post #33
lutorm wrote: post #10

Earlier quoted context omitted.

I don't endorse inches as a measure, but they are pretty intuitive. Maybe it's because the swedish word for inch is "tum", which means "thumb". And it happens to be 1.25 inches from the top of my thumb to the first joint.

An inch is (supposedly) measured as the _width_ of the upper phalange of the thumb, not as its length. And 'thumb' is its name in Dutch and French, too.

I have small hands. ;-)

Re: Grace Hopper on nanoseconds

#36

Post by Dylan16807 »

tripzilch wrote: post #9

That first paragraph was as good as unreadable thanks to all the miles, gallons and Fahrenheits. 11.8 inch ... times about 2.5 is umm wait it's a link, maybe if I hover it, no they didn't put metric in the title tags either. "In one millisecond, light travels 186 miles", which is about the same distance as a million squirrels put head-to-toe. Why not measure in squirrels? It makes about the same amount of sense, exce…

It would have been fine if they had rounded it slightly more to 1 foot. If you don't know how long a foot is, well it's about as long as your foot.

Re: Grace Hopper on nanoseconds

#37

Post by saurik »

shabble wrote: post #31

I can't view the video, so I'm not sure if it's straight up transcription error, or just confusion, but: the length of wire that is as long as light can travel in one nanosecond. The length is a very portable 11.8 inches. A microseconds worth of wire is a still portable, but a much bulkier 984 feet. Understanding the profligate ways of programmers, she suggests that every programmer wear a necklace of a microseconds…

Watch the video: not only does she hold a microsecond of wire up (so you can see what it is like), but she actually recommends hanging it on the wall above you desk (and as a joke). She then furthers the joke with the comment about hanging it around the neck, and it is specifically funny because it would be unreasonably heavy.

Re: Grace Hopper on nanoseconds

#38

Post by shabble »

moreati wrote: post #32
shabble wrote: post #31

I can't view the video, so I'm not sure if it's straight up transcription error, or just confusion, but: the length of wire that is as long as light can travel in one nanosecond. The length is a very portable 11.8 inches. A microseconds worth of wire is a still portable, but a much bulkier 984 feet. Understanding the profligate ways of programmers, she suggests that every programmer wear a necklace of a microseconds…

> but ~100 yards? Seems like a bit of a pain in the neck. That's the point - to serve as a constant reminder of how much circuit/processor time is thrown away for every microsecond it sits just waiting

There's a certain parallel to draw with the Iron Ring/Engineer's Ring[1,3].

Quoting from the latter article:

The Iron Ring is worn on the little finger ("pinky") of the working (dominant) hand; this would be the left hand for a left-handed person.[2] There, the facets act as a sharp reminder of one's obligation while the engineer works, because it could drag on the writing surface while the engineer is drawing or writing. This is particularly true of recently obligated engineers, whose rings bear sharp, unworn, facets

[1] https://en.wikipedia.org/wiki/Iron_Ring

[2] NMF

[3] https://en.wikipedia.org/wiki/Engineer%27s_Ring

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