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Vent #2

So, “pi day” is coming up. (Thanks for the reminder, Ms. H.).

I use quotes because March 14 has, aside from some matching digits, nothing to do with pi.

There are neither 10 months in a year, nor 100 days in a month, so there is no valid quantitative connection between 3/14 and 3.14. And even then, 3.14 is not pi. It is only an approximation.

I prefer April 26 – the day during which the earth’s travel around the sun since Jan 1 is equal to the mean radius of its orbit.

A much better rant than any I could summon up is available here. It’s a year old, but is definitely worth a read.

{ 5 } Comments

  1. Alane | March 6, 2008 at 2:53 pm | Permalink

    Excellent point – I thought I was the only one who couldn’t see the point in pi day. (I think pi is fascinating — just never could connect 3/14 with it.)

  2. Scott Franklin | March 14, 2008 at 7:57 pm | Permalink

    Yes, but what is so significant about January 1. Shouldn’t it be measured from some point in the year such as a solstice or equinox?

  3. Mr K. | March 14, 2008 at 10:01 pm | Permalink

    January 1st is indeed only socially significant. Solstice or equinox could work (and since we’re really talking about an ellipse, however slight, perihelion would be even more appropriate).

    It seems to me that for the purposes of pi, it doesn’t so much matter where you start measuring on the circle, as it does how far you’ve gone from the starting point. Since just about everyone knows when January 1st is, that seems as good a time as any. I’m willing to suffer that a lot more than the insistence that pi equals (rather than is approximated by) 3.14.

  4. Zac | March 15, 2008 at 4:44 pm | Permalink

    Thanks for the alternative suggestion, Mr K. I’ll keep it in mind for next year :-)

    Scott: The recognition of January 1st as the year’s start date is only a fairly recent phenomenon. It used to be March 1st, which as the start of spring in the Northern hemisphere, has more of a feel of “new year” than 1st January. It also makes a lot more sense when you think about September (meaning 7th month) and October (meaning 8th).

    I wrote on this in Christmas, Hari Raya and New year Math (first topic) and New Year’s Math (topic 5 near the end) in my newsletter.

  5. Zac | March 15, 2008 at 4:55 pm | Permalink

    Oops – I meant New Year was “in March” not 1st March. :-)