## Wednesday, December 28, 2011

After releasing episode 95, talking about how Febrary 7th is 'e
day', I started hearing from friends and listeners about other
math-related holidays.  Of course everyone knows by now about Pi Day,
celebrated on March 14th, since the constant pi, the ratio of a
circle's circumference to its diameter, equals 3.14.  For Pi day, or
any day celebrating a number expressible as an infinite decimal, you
can extend the concept further by taking additional digits to mean an
hour, minute, and second:  so on Pi Day, the very special moment at
1:59:26 pm is known as 'pi second', to celebrate the approximation
3.1415926.  If you prefer ratio-based approximations rather than
decimals, you can choose to celebrate days like July 22 for 22/7, or
December 20th (the 355th day of the year) at 1:13 pm for the
approximation 355/113.
But why should we stop at pi?  There are plenty of other
constants.  My unscientific impression is that the most popular day on
the net after Pi Day is Avogradro Day or Mole Day on June 2nd,
celebrating Avogadro's constant of 6.02 x 10 to the 23rd power, the
number of atoms of hydrogen that make up one gram.  You may recall
this constant mentioned before in the podcast: it's what helps us
count atoms and figure out the math doesn't add up for homeopathic
remedies, since homeopathic medicines are diluted by factors
exponentially greater than 10 to the 23rd, leaving no actual molecules
of the medicine.   Other constants that have inspired holidays include
the Golden Ratio, approximatly 1.61, which can be celebrated on
January 6th; or Root 2 day, celebrating the square root of 2 on
January 4th.
However, math geeks are always in search of patterns, and it
should not surprise us that other math holidays have been created that
have nothing to do with specific constants.  Recently on March 3rd we
celebrated 'square root day', since the month 3 and the day 3 are both
the square root of the last two digits of the year, 09.  These are a
little more interesting since there are only 9 per century:  January 1st
2001, February 2nd 2004, April 4th 2016, etc.  The celebration for
this day consists of eating square radishes, or other root vegetables
cut into square cross sections.  Personally, I prefer the eclairs we
got to eat on E Day, but I guess I should try to eat healthier.
Once this door is opened, who knows how many other holidays we can
come up with.  For example, here's one I just came up with:  why don't
we celebrate Relativity Day on May 13th?  That comes from looking at
the famous equation E=mc squared, and recognizing that E is the 5th
letter and M the 13th letter of the alphabet.  I was a little
disappointed to see online that there already is a Relativity Day,
celebrated on April 11th, the day Einstein came up with his theory.
But I like the idea of a celebration based on an actual equation,
rather than an accident of history.
This all starts to make me think about ancient Rome, where
there were eventually so many festivals that they began to outnumber
the working days.  (Not many of them were related to mathematics
though, so the Roman's weren't as cool as you might think.)  I decided
that rather than trying to come up with additional holidays myself,
I'll propose the first ever Math Mutation listener competition:
create a new math-related holiday, and email me the description and
justification, at my address erik@mathmutation.com.  If you come up
with an especially unique one or make me laugh, you will experience
the excitement and supreme honor of hearing your name mentioned in a
future podcast.
And this has been your math mutation for today.

• Pi Day at Wikipedia
• Square Root Day at Wikipedia
• Relativity Day