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How a piece of 166 year old graffiti was (partly) responsible for e-learning

Question: What is the link between an 19th Century Irish physicist and you, dear reader, viewing this blog post on your cool flat-screen monitor?

Answer: Quaternions!

Now read on…

Quaternions, in mathematics, are an extension of complex numbers. WilliamRowanHamilton

They were first described by the Irish mathematician Sir William  Rowan Hamilton in 1843 and applied to mechanics in three-dimensional space. They are used in both theoretical and applied mathematics, in particular for calculations involving three-dimensional rotations. Due to their use in describing spatial rotations, quaternions are used in computer graphics, control theory, signal processing, attitude control, physics, bioinformatics, and orbital mechanics. For example, it is common for spacecraft attitude-control systems to be commanded in terms of quaternions.

Today is the 166th anniversary of the moment of inspiration when Hamilton discovered quaternions.

For many years he had been trying to find a satisfactory way to multiply points in three dimensions, in such a way as to allow division. The idea of using four dimensions instead, and the way to do it. The story goes that on 16th October 1843, a bright October day much like today, Hamilton was out walking along the Royal Canal near Dublin with his wife when he had a ‘Eureka’ moment – the solution in the form of the equation

i2 = j2=k2=ijk=-1

occurred to him.

You know how it is – you can never find a pencil when you need one -using his penknife, Hamilton then carved this equation into the side of Broom Bridge for fear he would forget it.

For the last 20 years or so, my alma mater the National University of Ireland, Maynooth has organized a pilgrimage, where mathematicians take a walk from Dunsink Observatory in Finglas to Broombridge.

Sadly, no trace of Hamilton’s graffiti remains, though an engraved stone plaque does Quaternion Plaque, Broombridge, Dublin, Irelandcommemorate his discovery.

So maybe today, if you have a chance, you’ll tip your hat to one of the people who made it possible for us, as e-learning professionals, to create Web-based content, particularly when we design immersive simulations, and adapt virtual-world environments like Second Life for enhancing your audiences’ ability to learn.

As it’s a beautiful autumn day, I think I might go for a ramble down the Canal later to see can I find that stone with the historic scratchings…