Saturday, October 4, 2008

chaos, mojo, talisman, hoodoo, randomness and brownian motion

"Chaos = order without surface predictability." -Bala

"Talisman or amulet, a small object intended to bring good luck and/or protection to its owner



Mojo (pronounced /ˈmoʊdʒoʊ/) is a term commonly encountered in the African-American folk belief called hoodoo. A mojo is a type of magic charm, often of red flannel cloth and tied with a drawstring, containing botanical, zoological, and/or mineral curios, petition papers, and the like. It is typically worn under clothing.

"Spider's Nest Blues" by Hattie Hart and the Memphis Jug Band, Hart wants to go to New Orleans to get her toby (mojo) "fixed" because she is "having so much trouble" -- the mojo is protective and its power is wearing off, as witnessed by the "bad luck" she is having.



An amulet ( [Pliny], meaning "an object that protects a person from trouble"), a close cousin of the talisman (from Arabic طلاسم tilasm, ultimately from Greek telesma or from the Greek word "talein" which means "to initiate into the mysteries").

"Brownian motion (named in honor of the botanist Robert Brown) is the random movement of particles suspended in a liquid or gas or the mathematical model used to describe such random movements

Consider a large balloon of 10 meters in diameter. Imagine this large balloon in a football stadium. The balloon is so large that it lies on top of many members of the crowd. Because they are excited, these fans hit the balloon at different times and in different directions with the motions being completely random. In the end, the balloon is pushed in random directions, so it should not move on average. Consider now the force exerted at a certain time. We might have 20 supporters pushing right, and 21 other supporters pushing left, where each supporter is exerting equivalent amounts of force. In this case, the forces exerted from the left side and the right side are imbalanced in favor of the left side; the balloon will move slightly to the left. This type of imbalance exists at all times, and it causes random motion of the balloon. If we look at this situation from far above, so that we cannot see the supporters, we see the large balloon as a small object animated by erratic movement."

Einstein's Explanation of Brownian Motion; click here, this is a link. this is an animation showing a bunch of small balls making a bigger ball move around by randomly hitting it over and over again.


Below: Lucretius's scientific poem On the Nature of Things (c. 60 BC) has a remarkable description of Brownian motion of dust particles

"Observe what happens when sunbeams are admitted into a building and shed light on its shadowy places. You will see a multitude of tiny particles mingling in a multitude of ways... their dancing is an actual indication of underlying movements of matter that are hidden from our sight... It originates with the atoms which move of themselves [i.e. spontaneously]. Then those small compound bodies that are least removed from the impetus of the atoms are set in motion by the impact of their invisible blows and in turn cannon against slightly larger bodies. So the movement mounts up from the atoms and gradually emerges to the level of our senses, so that those bodies are in motion that we see in sunbeams, moved by blows that remain invisible."




all quotes except for Bala's taken from Wikipedia, September 30 and October 4, 2008.

1 comment:

jbailey said...

Brilliant Elaine! I would never have made the connection between your Mojo and Brownian Motion. Makes perfect sense though. 3D folks use Brownian formula's to create randomness in textures all the time. Interested to see where this goes for you. I think it is a very rich area.