In a world where the uncertain makes us look to the rational, people have always been fascinated by π, the constant irrational.
It is unsurprising that π has received its own day and less surprising still that it is 14 March or 3/14 in the US. Google celebrated π day 2010 by releasing a mock up of its trademark:

Since 2001 some mathematicians have pushed for another more basic irrational . The justifications are numerous. The essential case is that the formula on the right of the Google doodle is inelegant. My take on the argument is this:
- The circle is divine.
- The straight line is merely humanity’s attempt to get something right.
- The relationship between the straight line and the circle is captured by the formula on the right of the Google doodle: the ratio of a circle’s circumference (“C”) to its diameter (“d”) is π.
- But “d” is nowhere in the formula. It’s nowhere in the doodle.
- Instead, there’s only “r”, the radius. The diameter is just a human gloss, a couple of “r”s. In a world of R & D, humanity ignores the research and revels in the development.
- The law of parsimony and Occam’s razor leads to the conclusion that π is merely a demigod.
- The basic relationship between the profane and the sacred is better put as the ratio between the circumference and the radius, ie half the redundant diameter.
- Let us call that ratio by the Greek letter tau, τ, or better the one-legged π.
- And so the relationship becomes C = τr.
And so τ day is 28 June, or 6/28.
