Tau, which is twice the value of pi, is being proposed as a replacement for the best known constant in mathematics. It could be that the circumference of a circle will not use the traditional equation of 2πr, but will instead become τr, or tau multiplied by the radius.
There are a number of mathematical reasons for such a change, which I'm not going into here, but suffice to say there is much argument in the maths community on the proposed abolition of pi.
Today was chosen for the launch of this new constant as it can be approximated to 6.28 (hence 28 June).
You can read more on tau day on the BBC website.
JR
