Progress Report No. 1
I present
a simple model of a process that illustrates the following ideas:
A process has
the following properties:
1. A series of changes with a
goal. Usually the goal is a product.
It might be regarded as stream of matter, or
a channel through which products stream.
2. Is directed
in space (and time).
3. Has inputs
(other processes) and an output (another process).
4. Death: 1. A process disappears.
2. A process hits another process (acts as its input). Both
fuse and generate one or more processes (Birth).
The model might be the
elementary process (unit) of a WOB computer. Its unit, or bit is 'change' represented here by a cell.
The process (here the model) is the byte. Memory is part of the process.
Since each process manages its own time, WOB does not have a clock. Time
is relative.
The model was developed with StarLogoT2001
R2.(The Center for Connected Learning and Computer based Modeling. Northwestern
Unversity} It runs only on a Macintosh The model is written also in Mathematica.
This version will be available for inspection in the future.
The unit consists of a stem cell (blue) and transitory cells (red, green
and black). When stem cell divides it creates a (green) transitory
cell which is placed at the first location (loc = 1). The routine for stem
cell division is called stem-mitosis. Since stem cell continuously divides its
progeny advance (stream) upward. Some may divide again. They are called
progenitors (red) . Cell division of progenitors is done by a routine called
trans-mitosis. A third routine called shift-cells,
shifts cells upward. The three routines are
called enzymes They belong to the stem cell.
When cells reach the outer unit boundary, they die (black). Two
boundaries determine the fate of transitory cells. prog-max demarcates the highest progenitor position.
len-max demarcates
the position where cells die.
Input: Only the stem cell receives input (from the environment
Output: Dead cells are
the unit product and serve as output.
Only the stem cell receives
and processes input (from the environment). Part of the processed input
is inherited by its progeny. Information reaching the stem cell (resources
and demand) is stored in its chromosome. Both determine where len-max
and prog-max will be positioned. len-max[demand , resources]
and prog-max[demand , resource],
are updated during each stem cell division. Updated information is transmitted
to the first progeny (loc = 1) which carries it upward.
time (or chronological system
time) does not belong to the unit, and does not affect its behavior. It
serves for unit monitoring by an observer.
The right image describes some phases in the unit existence in the StarLogoT environment which is a matrix of 2000 x 2000 empty locations. At t-1 a stem cell is planted. This primordial stem cell which initiates the events to come is called zygote (blue). Zygote remains in a dormant state until demand requires its output (dead cells). When demand rises, the unit unfolds . At t-2 demand has risen to 10, and at t-3, to 20 and so on. All this time cells stream upward. As long as demand > 0 the unit flourishes. When demand = 0, zygote stops dividing and becomes dormant. Only demand drives this unit. The unit survives even a destruction of all transitory cells (green, red). It regenerates them all. Resources limit unit performance, yet do not drive it, as demand does .
The right image of the unit above, highlights other properties of the unit.
stem-mitosis generates the main process.
trans-mitosis
generates secondary processes.
Each additional progenitor cell
(red) generates a new process.
Chromosome stores long term memory. Transitory cells carry short term memory.
How short term it is depends on demand and resources. Thus short term
memory[demand, resources].
For instance, a cell a loc = 1 inherits prog-max and len-max. The unit remembers it as long as the cell lives, which depends on demand and resources. A cell at loc = n carries information generated by the stem cell n-time-steps ago.
As the unit evolves, chromosome is updated. It stores the unit configuration at a particular moment. Suppose that at time = n you took a zygote and planted it in an isolated environment. It will always generate the same unit. At each time step the unit will settle at the same attractor. Provided that the environment will accept the demand stored in the chromosome. On the other hand if environment enforces its own demand upon the unit (as the environment is expected to do), the stem cell will apply its experience to handle this new challenge (input).
Two zygote histories are depicted.
The left one is a zygote history at a constant demand = 10. Each point is
the (normalized) Euclidean distance of the current chromosome to the chromosome
when zygote was first planted (t=1).. The right image depicts a zygote
history when demand rose linearly from 1-60.