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Fractals Without A Computer

scientopia.org

94 pointsbigfoot14 comments

_Godel, Escher, Bach_ describes similar phenomena with camera feedback loops. When I read GEB, I wondered if it would be possible to create a Sierpinski triangle using four specially shaped/curved mirrors. I briefly played with povray, but didn't figure it out.

Growing them:

http://www.fourmilab.ch/images/Romanesco/

You can do something similar, although not quite as intricate, by simply pointing your webcam at a computer screen that is displaying the webcam-feed. You get infinitely repeating patterns that respond in beautiful ways to subtle tilts and nudges of the webcam. It's really pretty impressive and worth 5 minutes of your time if you have an external webcam around.

Now all you need is an app that shows the video feed in multiple windows you can drag around and you can get the exact same effect.

Or with Mac OS X screen sharing, VNC, or similar.

This is awesome. Someone finally figured out a clever use for the camera feedback loop.

Someone figured out a use a long time ago: the Doctor Who (British SciFi) opening sequence. And apparently before that for Amahl and the Night Visitors, a drama broadcast in 1951: http://www.bbc.co.uk/dna/h2g2/A907544

Example feedback patterns: http://www.youtube.com/watch?v=C8Xm3EA3_XE

Technically most fractals occur without a computer.

Like when they were discovered!

Doesn't it depend on your precise definition of Fractal. In nature they're not self-similar repetitions at altered scale but approximate the same¹. There is always a limitation in nature of resolution (lumpiness of atoms) just as no true circle can exist in nature (at least in our realm Plato², please correct me if I'm wrong).

So technically most (all I think) fractals do not occur extent in reality but only the mathematical description of them occurs.

¹ note the precise definition of "similar" in geometry, http://en.wikipedia.org/wiki/Similarity_%28geometry%29. ² I can't recall Plato's take on [perfect] forms of biological "shapes" like trees and such.

Does real-time video not at the very least involve a micro-controller? So arguably this is one way to make fractals WITH a computer. It looks cool and video feedback does make nice effects.

"what they’ve done is set up three screens, in a triangular pattern"

Triangular pattern doesn't say very much. Is this supposed to mean that the trick will work iff the screens are not collinear?

Try and get back to us.

Personally, i think this speaks to the way time works - but i've done A LOT of mushrooms....

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