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It's Square Root Day! Prepare to Be Somewhat Underwhelmed...

It's kind of like Pi Day, but way, way less fun

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Math geeks and those who love them are probably still in withdrawal: Pi Day, the holiday that commemorates everyone’s favorite irrational number, has come and gone, and the next one won’t happen until March 14, 2017—an agonizing 11-plus months in the future.

But wait, you say. Isn’t today another major math-related holiday? Four times four, or 42, is 16, and since today’s date is 4/4/16, this is—wait for it—square root day! It happens every time this sort of configuration rolls around: the last square root day was March 3, 2009, or 3/3/09, and the next will happen on May 5, 2025, or 5/5/25.

Before you get too excited, though, you need to face a sad truth: square root day is a second-rate math holiday at best—it’s like trying to get your pulse pounding over Arbor Day, compared with, say, Christmas or Thanksgiving or any other self-respecting festival. Here are just a few reasons:


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  • Pi Day is associated with Albert Einstein, who was born on that day in 1879 (Pi Day itself wasn’t invented until 1988, but the great physicist definitely used Pi in his equations). Square Root Day is associated with… Opening Day for Major League Baseball. Approximately, anyway.

  • Pi Day comes every year. Square Root Day comes nine times a century (or ten, if you agree that last number in 10/10/00 represents 100 rather than zero). And you usually have to wait longer for the next one than you did since the last one (seven years since 3/3/09; nine until 5/5/25). What kind of holiday is that? Who can even remember?

  • Pi Day has T-shirts. (OK, Square Root Day does too, but by the time the next occasion to wear it comes around in nine years, will yours still fit? Be honest.)

  • We celebrate Pi Day by eating some of our favorite round foods (you remember that Pi represents how many times you have to multiply a circle’s diameter to get its circumference, right?). These traditionally include pizza and pies (a pizza joint in Einstein’s adopted town of Princeton, NJ is even named Princeton Pi). The organizers of Square Root Day suggest eating root vegetables (get it?) that have been cut into squares. Are you salivating yet? No, I didn’t think so.

  • The first three numerals of Pi (3.14, but I didn’t have to tell you that), seen in a mirror, spell out the word “pie.” Try looking at “square root day” in the mirror. You won’t find it enlightening.

Of course, Americans are notably math-phobic, so encouraging them to see numbers as fun and celebration-worthy is a good thing. Last time around, Scientific American posted its own dutiful blog about Square Root Day. Let’s just say that even the author didn’t feel much excitement about the whole thing.

Not only that: he had to acknowledge a commenter’s point that the inventors could just as easily have called it “Square Day,” and that 9/3/03 and or 4/2/02 could qualify just as plausibly as the current format. Square Root Day is kind of lame, in short, on multiple levels.

But if you think there’s no such thing as too many math celebrations, Square Root Day is by definition something to celebrate. While you’re at it, you might as well gear up for Fibonacci Day (11/23), Pythagorean Theorem Day (the date varies), and Math Storytelling Day (9/25)

When it comes to math holidays, in short, the fun—such as it is—never stops. Me, I'll just wait for next Pi Day. I'll be entering the Einstein Look-Alike Contest.