Happy Tau Day

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mathematics, mathemusician, maths, nerd, pi, Tau day, Vi Hart

Pi is not all it’s cracked up to be.  The problem with pi, is that a pie is 2 pi.  Tau, which is 2 pi, is much better.

Confused?

Here’s my favourite mathemusician to explain.

So, instead of celebrating pi day (3/14 or March 14), I am celebrating Tau Day (6/28, or June 28).  You should too!

Fibonacci rules

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ammonite, Fibonacci, fibonacci sequence, fibonacci spiral, fossil, math geek, mathematics, maths, nature, number theory, patterns in nature, spirals, Vi Hart

That title’s a pun.  I’d say that most of the time, if you have a suspicion, err on the side of pun.

I wanted to write about one of the coolest universalities of nature: Fibonacci sequences.  Fibonacci was “the most talented western mathematician of the Middle Ages,” according to Wikipedia.

A Fibonacci sequence always starts with 0 and 1, and every following number is the sum of the previous two.  Here are the first few numbers, just so that you get the idea:

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55…

But, unless you are a math geek, any old sequence of numbers is not particularly interesting, until…

Fibonacci ammonite

This is a photo of a fossilized ammonite that my friend bought for me at the Darwin house in Kent, UK.  (Have you been?  Was it awesome?)

The ammonite is not only beautiful, it is inevitable.  To explain, here is my guest, Vi Hart, the most amazing mathemusician in the world.

So, when you look at the arrangement of florets in a sunflower, or spirals on a cone, or spirals on a pineapple, or the spiral of an ammonite, you’re looking at a Fibonacci spiral.  If you’re clever and have an incredibly long name, like Przemysław Prusinkiewicz, maybe you can also notice that the heredity in bees and the breeding of rabbits also fit into the Fibonacci sequence.  (Okay, so maybe it is not a requirement to have a long name.)

But there are exceptions, right?  There are plants that have opposite and alternate leaf arrangements, that don’t fit into these perfect Fibonnaci sequences.  In order to understand these exceptions, here is Vi Hart again…

It makes a lot of sense…plants aren’t specifically trying to follow a particular angle, they are just trying to maximize the amount of sunlight each leaf receives.  And they can achieve this goal by just growing in a logical way, by following a growth hormone.

Vi Hart is really the best and, if you like finding out about these sorts of patterns, you should check out her other videos.  My favourite quote of hers is: “This pattern is not just useful, not just beautiful, it is inevitable…you discover things that seem impossible to be true and then discover why it is impossible for them not to be.”