Pieces of String

Just how long is a piece of string?

a) Twice as long as a piece of string half its length?
b) Just long enough to join its ends?
c) 10e-35 metres
d) As long as my current Mathematica calculation?
e) Shorter than when you last measured it

In the case of d), this calculation has now been running for 17h15m (that's 62,100 seconds), consuming on average about 50% of the power of my Core Duo T7200 processor (and only 400MB of memory), which clocks up about 11 billion instructions per second.

So... thus far the laptop has executed about 310 trillion (that's 310,000,000,000,000) instructions.

Now, for idle comparison - assume the engine of your car runs on average at say, 2,500 RPM while doing 70mph and that it lasts say 200,000 miles

By the time the engine wears out in 2857 driving hours it will have done 428 million revs. If the CPU lasted 428 million cycles it would have worn out in only 42 milliseconds, I would be getting through CPU's at the rate of about 24 per second and would already have got through 1.5 million of them.

Or, looking at it the other way, if your car was only as reliable as the CPU has been for the past 17h15m it would go about ten trillion miles, which is about half way to Alpha Centauri (though at 70mph it would take you about 39 million years)

That's LONG string.

BTW - all the above calculations are highly dubious: I've corrected them twice already. Can't rhyme, can't add. What to do?

The Dogon of Mali, Sirius and Stuff

Here is a Dogon joke:

Q: How many people are there in a Dogon family?
A: Five - two parents, two children and a French anthropologist.

Anthropologists just love the Dogon - and why not, they are a fascinating people - Mali is on my list of Must-See places as soon as IT is finished and I reap the reward of some hard earned globe-trotting (No, you may not go first Dean - I mentioned Namibia once and the next thing I know he's swooping over the desert at head height in a light aircraft!).

Anyway, the Wikipedia article is rather long on the whole "Sirius Mystery" angle: how come the Dogon know so much about Sirius - and even the existence of Sirius B which you need a pretty large telescope to see, etc. etc. eh?

Unfortunately, no one is without a reasonable argument: they learned all about Sirius from aliens (who, after all, should be expected to know) or they learned about it from missionaries - the god-bothering brigade of olden days, being gentlemanly in their pursuits, being rather keen on the whole astronomy thing don't you know?

However, I digress... but before returning to the topic, where did I hear that the Dogon also talk of Sirius C - whose existence wasn't detected until a very few years ago? Hmmm? Are missionaries now providing real-time hookups to Hubble as they go? [Found it: le Renard Pâle, p475... "The star emme ya” emme ya tolo is more voluminous than po tolo and four times lighter. It also orbits around Sirius...]

Anyway, what the Wikipedia article doesn't mention are some other, y'know, like "wow!" things the Dogon believe in... if you put the right spin on them.

This came home to me as I was reading Essai sur las Cosmogonie des Dogon a book by a French anthropologist (see?) called Eric Geurrier, which also references the seminal work mentioned above, "Le Renard Pâle" by Marcel Griaule and Germaine Dieterlen, 1965 (guess their nationality and occupation!).

According to this, the Dogon speak of le "monde d’étoiles en spirale" - the spiral word of stars - which sounds remarkably like a galaxy to me... furthermore, they don't just speak of Le Monde, they speak of Les Mondes, a veritable plethora of galaxies.

But, they are not merely masters of the macrocosm, they are pretty good on the microcosm too... this is the (heavily edited and badly translated by me) story of creation:

In the beginning, before all things, was the god Amma, who rested on nothing. The rolled-up ("en boule") egg of Amma was closed [in upon itself], but divided into four pieces called “clavicles”

The four clavicles are equally prefigurations of the four elements the “four things” water, air, earth and fire; similarly the bisections which separated them, marked the four collateral directions the “four angles”, which is to say, space

But Amma was not very pleased with the result, so he started again...

‘Oeuf D’Amma” Second Genesis (again my translation from the French)

He opened his eyes. This act caused the emergence of the yala from the spiral which, turning in the egg prefigured - in the interior of the egg - the future expansion of the universe.

Thus Amma had pierced the envelope of his breast, and his “eye”, appearing as if from a hole, had become a light, which lit up the universe and revealed the existence of all things in creation.

The universe in the breast of Amma was timeless and without extent, space and time merged by mutual agreement.

When I read this, I was astonished to find myself contemplating the very creation of space and time, their intrinsic inter-connectedness, the Big Bang, etc. etc. described in mythic terms by the Dogon. [If only I could track down the article I read once in which somebody brilliantly re-wrote modern particle physics as a piece of wizardry on a par with Lord of The Rings]

But, enough about Sirius already- lets big-up the Dogon for their whole intuitive appreciation of Special Relativity, General Relativity, cosmology, the Big Bang, etc. etc. and come to think of it, the whole en-boule thing which is really about Grand Unification of the four forces, possibly even, via the "chevron dance", anticipating String Theory.

Can I make this an urban myth? Nope - that's up to you!

PS French anthropology is great! You should read "The Raw and the Cooked" (Le Cru et le Cuit) by Levi Strauss - he has a wonderful transformational theory that can explain everything.