Systems that are Sensitive to Initial Conditions

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Systems that are sensitive to initial conditions are those that whose trajectories diverge in ways that are not predictable. One of those systems is the chaotic Lorenz attractor, but even simpler systems can show dependence on the initial conditions.

In this example the diverging behaviour is obtained by the totally deterministic algorithm 2 times modulo 1 or (2x%1) that you can even try out in your calculator.

  1. take a random number between 0 and 1 (e.g. 0.823)
  2. multiply that number by 2 (e.g. 2*0.823=1.646)
  3. calculate the modulo 1 (%) of this value (e.g. 1.646 % 1=0.646). modulo 1 corresponds in this case to make the integer part of the number 0.
  4. use the result obtained in 3. and repeat from 2.

Now start with a second number that is very similar to the first (e.g. 0.825) and repeat the process (in the animation the initial difference is just 0.01% between the two values). You’ll see that for the first iterations the results (the trajectory) stays close to the first case but suddenly it jumps all around. It looks that after some iterations you can’t predict the behaviour of the second trajectory, even if you knew the first trajectory. This clearly shows that this system is sensitive to the initial conditions. A very simple and strange system indeed.

  2014/08/29 9:57 PM

Lucy, not really a must go and see film


Take a good idea, a potentially great idea, and put it in the hands of a director (Luc Besson) that is known for stories of triads, professional assassins and revenges and you get Lucy. But the problem is that the brain expansion and the Taipei triad scenario don’t match.

This movie was going to be all about execution, and it doesn’t deliver. It is not even entertainment. The director uses the same tricks every time (Corridors for example: in one case Lucy makes every french cop fall to the ground with the flick of a finger, in another every mob member flies into the ceiling, and while the former was kind of fun, the latter is just dull, dull, dull, and repetitive).

The movie doesn’t really build to a climax, there is no surprise or twist of events, it isn’t about an hero trying something, it isn’t about a conspiracy, it isn’t even about trying to survive the Taipei triad while trying to understand the universe by your expanding brain. It is just a BAD summer movie, backed by two well-known actors and lot’s of publicity.

Ah, the actors! Scarlett Johansson plays the role but somehow the scenes where she walks into or out of rooms, corridors, etc. didn’t convince me. She doesn’t have the walk. She’s competent, but not much else is there. She is not very expressive in the action parts of the role and is better in the close up dialogs and interactions mainly due to her magnetic look. Morgan Freeman playing the role of a scientist teaching in the Sorbonne is now doing these roles of the “expert” that gives instant credibility to any story (was the same thing with Transcendence). In the end they are the duck calls for people to go and see the film. They do their job, but no one will remember them for this movie.

One final thing. What was that in the end of the film, were after building the most powerful next generation super computer that looked like a live termite ant tower, the computer expends a protuberance to give “All knowledge a 100% brain has” to Morgan Freeman in a USB stick? WHAT? And a big clunky one too! And Morgan Freeman stands there, astonished, holding the USB stick in the air and probably thinking “Is this what I’m doomed to do for the rest of my acting career?

  2014/08/29 8:49 AM

R Tip: ggplot axis labels

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  2014/08/18 2:47 PM

Siri’s Inventors Are Building a Radical New AI That Does Anything You Ask

The inventors of Siri are confident that their next creation will eclipse the first. But whether and when that will happen is a question that even Viv herself cannot answer. Yet.via Siri’s Inventors Are Building a Radical New AI That Does Anything You Ask | Enterprise | WIRED. Are we getting to the point of [...]

  2014/08/17 12:39 PM

Is the singularity cost prohibitive?

The idea that a technological singularity is going to hit us any time in the future and that at that moment in time we’ll be presented with (now) unimaginable artificial intelligence (or at least greater than human intelligence, and that’s not saying much because on its own greater-than-human-intelligence is full of caveats) is a recurrent [...]

  2014/07/21 3:42 PM

How Educators Around The World Are Implementing Mobile Learning And What You Can Learn From Them

Still, UNESCO reports that 250 million students worldwide cannot read, write, or count, even after four years of school. Close to 775 million adults– 64% of whom are women–still lack reading and writing skills, with the lowest rates in Sub-Saharan Africa and South and West Asia.via How Educators Around The World Are Implementing Mobile Learning [...]

  2014/07/21 10:01 AM

Global Brain: Web as Self-organizing Distributed Intelligence – Francis Heylighen

OVERVIEW: Distributed intelligence is an ability to solve problems and process information that is not localized inside a single person or computer, but that emerges from the coordinated interactions between a large number of people and their technological extensions. The Internet and in particular the World-Wide Web form a nearly ideal substrate for the emergence [...]

  2014/07/18 9:02 AM

Os regulamentos da cidade islâmica

As leis islâmicas al-fikh abrangem a organização urbana das cidades islâmicas; não segue à risca as imposições de um plano, defende os interesses da família, e revela um modo autossuficiente de fazer cidade, sustentado por suas próprias leis. via arquitextos 169.04 oriente: Os regulamentos da cidade islâmica | vitruvius.

  2014/07/15 7:33 PM

Justin Reich on MOOCs and the Science of Learning

Millions of learners on platforms like edX and Coursera are generating terabytes of data tracking their activity in real time. Online learning platforms capture extraordinarily detailed records of student behavior, and now the challenge for researchers is to explore how these new datasets can be used to advance the science of learning. In this edX [...]

  2014/07/09 10:27 AM

As listas que para aí se fazem

Portugal é o país das listas, de apoio, de censura, para tudo e mais alguma coisa, até para se sair das listas é preciso subscrever outra. Um país de amorfos alistados.

  2014/07/07 6:04 PM

Why I gave up on Evernote

Evernote has been bon out of a great idea, but in the end didn’t evolve into anything special. Looks like a last decade application right now. It is dated in some aspects that one would think a modern note taking application should have Space and features. The basic free account limits are pre-historic for modern [...]

  2014/07/05 9:45 AM

Notas sobre futebol – o debacle Português no Brasil

Como todos os que viram o jogo da selecção Portuguesa contra a Alemanha, também tenho uma opinião que mais do que analítica é intuitiva. Certamente alguns concordarão com alguns dos meus pontos, alguns certamente discordarão. Ainda bem! AINDA (mesmo que alguns não gostem) é possível discordar neste país. Mais uma vez vi o Nani a [...]

  2014/06/17 4:33 PM

Pulley Logic Gates – Just Brilliant

Pulley Logic Gates from Alex Gorischek on Vimeo. Just come across this video of physical logic gates made with some a board, some string and weights. Just brilliant and instructive for any computer geek out there.

  2014/06/03 9:41 AM

Traversing News with Second Order Swarm Intelligence

Figure – Two simplicies a and b connected by the 2-dimensional face, the triangle {1;2;3}. In the analysis of the time-line of The Guardian newspaper (link) the system used feature vectors based on frequency of words and them computed similarity between documents based on those feature vectors. This is a purely statistical approach that requires [...]

  2014/05/28 6:16 PM

As eleições “para quê votar?”, dizem eles!

Há algo que me incomoda na forma como a direcção geral da administração interna decidiu não repetir as eleições nas freguesias que boicotaram no domingo com o argumento de que não iriam nunca afectar os resultados. Trata-se de um entendimento do acto eleitoral completamente obtuso, “que só serve para eleger políticos”, e nada mais. Votar [...]

  2014/05/27 9:46 AM

O Expresso Diário

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  2014/05/07 9:39 AM

Switching to Colemak (part 2)

After deciding to learn Colemak to improve my touch-typing speed in the beginning of the month, I decided to give you an update on my progress: After maybe one week I already knew the layout, but the speed was very slow, maybe 10wpm. This made it impossible to use it daily and therefore I kept [...]

  2014/04/23 10:17 AM