
Why Pi Matters - plg
http://www.newyorker.com/tech/elements/pi-day-why-pi-matters?mbid=social_twitter
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hobarrera
It's really only "pi day" for a single country around the world that uses a
notation that nobody else can understand
(mediumUnit.smallestUnit.largestUnit).

I'm also surprised that US still uses two-digits for years, as in "3.14.15", I
though the changes brought by on Y2K had been worldwide.

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yeukhon
I believe, but correct me, in Pi, there is no repeating pattern known to exist
yet. So you can encode information in Pi. No? I heard this from watching
Person of Interest...

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acomar
These are unrelated concepts and the latter is unproven but conjectured. Pi's
irrationality is sufficient to show that there is no point after which the
digits of pi lapse into cycles. However, it's conjuctured that pi is also a
normal number[1]. The square root of 2 and e are also conjectured to be
normal, though a proof again does not exist. It has been proven however that
the vast majority of real numbers are infact normal, but the proof isn't
constructive so specific examples largely elude us.

[1]
[http://en.wikipedia.org/wiki/Normal_number](http://en.wikipedia.org/wiki/Normal_number)

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Chinjut
Specific examples of normal numbers are super easy to construct. Here's one
(in base 10): 0.01234567891011121314...

[I am using "normal" to mean normal in a specific base, not necessarily normal
in all bases (i.e., not necessarily "absolutely normal"). But this is all that
is necessary for the idea of encoding information via the digit expansion of a
constant]

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pronoiac
In San Francisco, the Exploratorium offers free admission for Pi Day tomorrow.
Yay, Pi Day!

