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Monday, September 2, 2002   
Prime Stuff

Almost everyone has the intuition that there must be some kind of "order" to prime numbers. But perhaps they are an example of what Wolfram calls "The Principle of Computational Irreducibility." We know how to test them, but not how to generate them efficiently.

But maybe we'll be able to sneak up on the little buggers. Certainly it would be nice to think so.

10:03:55 PM      

Circuit to Computer: 'Come in, please!'

Using a computer-based genetic algorithm (selecting for an attribute after "mutating" variables), scientists trying to evolve a oscillator circuit managed to create one that turned into a radio receiver... serving up a nearby computer's signal as output.

Paul Layzell and Jon Bird at the University of Sussex in Brighton applied the program to a simple arrangement of transistors and found that an oscillating output did indeed evolve.

But when they looked more closely they found that, despite producing an oscillating signal, the circuit itself was not actually an oscillator. Instead, it was behaving more like a radio receiver, picking up a signal from a nearby computer and delivering it as an output.

In essence, the evolving circuit had cheated, relaying oscillations generated elsewhere, rather than generating its own.

And despite not being explicitly selected for, the circuit had also grown itself an "antenna."

This just tickles me.

It's somehow anxiety-provoking too. (Sometimes nature doesn't ask, "Would you like a side of fries with that?" ~ sometimes you just get the Meal Deal automatically.)

4:51:55 PM      

Negative Self-Talk

Here we go:

I think I blew it
I feel fat and ugly
On ne peut jamais gagner

The body thing is going to go south. Somehow the good stuff doesn't stay in my brain: a good flute lesson, a 21-year old guy who spent an hour and a half talking to me, a house full of interesting guests (names you'd recognize, maybe, if I hadn't edited them). No, I'm worried about eating too much, and planning to skip meals. Being fifteen is so much fun.

1:18:53 AM      


© Copyright 2002 Pascale Soleil.
Last updated: 10/1/02; 12:47:23 AM.
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