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A comment on The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ milliseconds is exactly 1 day. Parent comment

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by monochromatic on Saturday December 09, 2017 @07:34PM (#15889021)
Slightly off topic, but my favorite units for c are feet per nanosecond. In those units c = 1 (plus or minus a couple of percent).
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by bouvin on Sunday December 10, 2017 @05:07AM (#15890761)
No mention of the foot per nanosecond is complete without this seminal scene between the great, late Grace Hopper and David Letterman: https://youtu.be/1-vcErOPofQ?t=4m43s
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by contravariant on Saturday December 09, 2017 @10:45PM (#15889747)
It's even closer if you use a 'metric foot' of exactly 30 cm. Then you're only off by 0.1%.
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by monochromatic on Saturday December 09, 2017 @11:33PM (#15889934)
> metric foot

Why is that a thing?

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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by contravariant on Sunday December 10, 2017 @07:57PM (#15894460)
Not sure, but most of those 'metricised' units are leftovers from Napoleon's push to make everything metric.
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by sixothree on Sunday December 10, 2017 @12:12AM (#15890053)
Maybe because 30cm is very close to 12 inches.
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by letlambda on Sunday December 10, 2017 @02:43AM (#15890439)
Which leads to my favorite way to think about it. One foot per clock tick of a 1Ghz processor.
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by stephengillie on Sunday December 10, 2017 @10:09AM (#15891709)
Does this mean circuits in a 1 GHz processor can't be longer than 12 inches?
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by todd8 on Sunday December 10, 2017 @11:36AM (#15892131)
No information can travel more than a foot (11.8 inches) in a nanosecond. Grace Hopper used to give a talk where she held up a piece of wire that was that long to illustrate this limitation. [1]

The first Cray computers were designed in a cylindrical shape to keep the signal wires short. [2]

[1] https://www.youtube.com/watch?v=JEpsKnWZrJ8

[2] https://en.wikipedia.org/wiki/Cray-1

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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by linker3000 on Sunday December 10, 2017 @06:50PM (#15894190)
'twas an annular shape!

Ok..the backplane was annular

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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by 18nleung on Saturday December 09, 2017 @08:18PM (#15889201)
That's really interesting - only about 2% off.

Conversion Here: https://www.wolframalpha.com/input/?i=speed+of+light+in+feet...

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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by Cerium on Sunday December 10, 2017 @11:49AM (#15892201)
Mine are gigahertz * inches. 11.8ghz * in is the speed of light. Gives you a feel for it and is practical. Want to find an antenna length? Ghz*inches are your friend.
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by boyce on Sunday December 10, 2017 @02:59PM (#15893201)
That is great, never heard that one. Thanks
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Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by jeffwass on Sunday December 10, 2017 @03:09AM (#15890496)
I always like the fact that there are π seconds in a nanocentury (within half a percent)
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