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… or how to grow crystals in the lab.

When voltage is applied to electrodes placed in a solution of positively charged metal ions, the ions will attract to the negatively charged electrode, convert to neutral metal atoms and stack together in crystal form. Branches of crystalline metal deposit grow from the cathode (-) to the anode (+) when high voltage is applied. The branched clusters of metallic crystals represents a non-equilibrium structure, and give similar results as diffusion-limited aggregation systems. In the industry this process is used to cover surfaces with metallic coats, the use of less voltage ensures uniform coating over the surface.

Roots by Roman Kirschner (2005-2006) Here in a brownish liquid several electrode wires supply voltage and cause iron crystals to aggregate on them. The growth of the crystals influences the flow of electricity as the crystals try to make connections between the wires. The voltage of the wires is measured and transformed into sound output. Regularly crystal branches break off and sink back to the ground and a new cycle of growth starts.

Dendrite by Pablo Miranda Carranza (2005) Dendrite is a electrochemical computation device and based on Gordon Pask's self-repairing and evolutionary electro-deposition systems. Several platinum electrodes (4×4 matrix) connect to the electrolytic bath (saturated alcoholic solution of stannous chloride). The anodes supply voltage in form of pulses to the solution and the cathodes pick up the current and convert it back to digital. Miranda uses the results for architectural 3D transformations. Alternatively the setup can be used for weighted neuronal networks. Crystal growth can form connections between anode and cathodes (wiring between neurons) and the growth form can indicate the strength / weight of the connection.

See: To evolve an ear: epistemological implications of Gordon Pask's electrochemical devices by Peter Cariani (1993)

Scientist Stephen Wolfram presents his book A New Kind of Science (available for free online) at a lecture held at UC San Diego in 2003. Wolfram, who received his Ph.D. in particle physics from Caltech at age 20, is the developer of the computer algebra system Mathematica and will soon (May 2009) release Wolfram Alpha - a computational data engine based on intuitive query parsing and a large library of algorithms that computes answers and visualizations.

In the talk he shares his perspective of how the unexpected results of simple computer experiments have forced him to consider a whole new way of looking at processes in our universe. He anticipates the discovery of the ultimate simple program that runs our whole universe.

He mainly talks about the emergence of complexity and randomness from a set of simple rules. Prominently featured are simple computational systems like the one-dimensional binary Cellular Automatons and the special cases of Rule 30 CA and Rule 110 CA. Out of the 256 possible rule-sets of one-dimensional binary CA, these two result in complex and seemingly random outputs:

Additionally Rule 110 CA is Turing complete which means it can simulate a universal Turing machine. This grounds Wolfram's conclusion that the universe is digital in its nature, and runs on fundamental laws which can be described as simple programs like Cellular Automata.

More examples of simple rule sets leading to complexity:

• Turing Machine rules (1 cell at a time is updated)
• Sequential substitution systems
• Snowflakes (heat of water vapor prevents crystallization of neighbor cells)

Randomness is achieved …

• through external perturbations (Brownian Motion)
• intrinsically, because of sensitive dependency on initial conditions (chaos theory, rule 30 and 110 CA), which makes the outcome predictable!

He argues that complexity in nature is not necessarily the result of evolution and natural selection, as natural selection doesn't operate well on high complexity levels. The pigment patterns on seashells, or the shapes of leaves seem to be chosen randomly instead of by natural selection.

More topics:

• Causal invariance
• Principle of computational equivalence
• Computational irreducibility
• Undecidability

Philip Beesley's Hylozoic Soil won the first price at this years VIDA 11.0 competition.

Hylozoism is the belief that all material things possess life. With Hylozoic Soil Beesley created a responsive and smart environment out of thin translucent laser cut acrylic forms, actuated with shape-memory-alloy and equipped with proximity sensors. The whole environment consists of an interconnected network of clusters controlled by several Arduino processors and custom-made daughter-boards. The clusters have a mesh-like skin and a muscle system of several tendril arms that are made to coil and uncoil in organic movements with Nitinol wire. Waves of so-called breathing and swallowing roll through each cluster if the proximity sensors are stimulated. And, best of all, Hylozoic Soil is not harmless: Apparently there are needles attached to pierce yoru skin, and collector barbs for grabbing hair and clothing!

Besides the visually very haunting and mesmerizing character of Hylozoic Soil, i favor this piece because it incorporates lightweight rapid-prototyping materials, nature-inspired artificial muscle actuators and complex system behaviors. In my opinion the perfect direction for artificial life art: screen-less, without noisy motors, and showing intelligent systems with the bottom-up approach.

Philip Beesley is an British/Canadian architect and artist, who explores new technologies and materials for his interactive responsive environments. All his projects look absolutely stunning, they always have a mesh-like character and he makes good use of new digital fabrication techniques. And besides art installations, he and his company design houses and create stage designs. What a busy man he must be!

Cybele - Cambridge, ON - 2005

Reflexive Membranes with Diane Willow and Stephen Wood - Cambridge, ON - 2004

Binaural beats are auditory processing artifacts, apparent sounds that appear in your head when each ear listens to a slightly different frequency tone. The beat, which would be audible if the two tones would be mixed naturally, is only perceived in the brain. For the effect to occur the tones should be below 1000 Hz and have a difference of below 30 Hz.

So far so good. Now, the interesting part is, that the occurrence of binaural beats in the head can influence the frequency of the listeners brain waves. The predominant brain waves frequency is said to be likely to move towards the frequency of the perceived binaural beats. Depending on our activity our brainwaves have different frequencies:

• Delta waves (< 4 Hz): deep dreamless sleep
• Theta waves (4-7 Hz): dreams, meditation
• Alpha waves (7-13 Hz): relaxation
• Beta waves (13-40 Hz): active, concentration
• Gamma waves (> 40 Hz): high mental activity, perception, fear

Depending on the frequency of the binaural beats, one can provoke relaxation (by lowering the brain frequency) or alertness (increasing the brain frequency), different states of consciousness. This effect has been used f.e. to reduce learning time and sleeping needs, treat addictions, recover repressed memories, provoke lucid dreaming, or create out-of-body experiences.

Besides with audible tones, the effect can also achieved with visual, or a combination of aural and visual stimuli. Most famous is the [http://en.wikipedia.org/wiki/Dreamachine|Dreamachine], a stroboscopic flicker device (a cylinder with slit cuts turns on a record turntable while a light bulb is place in the center of the cylinder) created by artist Brion Gysin (famous for inventing the Beat Generation's cut-up technique) and scientist Ian Sommerville. You view it with your eyes closed, but the flickers still stimulate your optical nerve. You experience complex color patterns until you enter the transitional state between wakefulness and sleep. People with photosensitive epilepsy (one out of 10.000 adults) will perceive a seizure when perceiving these flashing lights in regular patterns. They have to watch out when it comes to disco lights, video games, TV programs and even webdesign: In 1997 the screening of a particular Pokémon episode in Japan triggered seizures in hundreds of susceptible viewers, because of a sequence of flickering images. In 2008 hackers placed a animated gif image flashing at high speed on the forum of an Epilepsy website (!!).