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Cellular Automaton. Written and Presented by: Craig Schweitzer. Cellular Automaton-Summary. What is cellular automaton? History of cellular automaton Simple cellular automata The practical uses of cellular automaton The Game of Life. What is Cellular Automaton?.
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Cellular Automaton Written and Presented by: Craig Schweitzer
Cellular Automaton-Summary • What is cellular automaton? • History of cellular automaton • Simple cellular automata • The practical uses of cellular automaton • The Game of Life
What is Cellular Automaton? Cellular Automaton(CA): A regular spatial lattice of cells, each of which can have a finite number of states. The cell states are updated in discrete time steps and defined by its original state and the state of the cells surrounding it.
How Cellular Automaton Began In 1947, John von Neumann was working in the field of science, focusing on biology. He was studying a self-replicating machine when he designed a two-dimensional CA model of the physics of our universe. He mathematically proved that the universe he made acted like a self-replicating machine and that it would make endless copies of itself.
What is Cellular Automaton?(cont’d) Every separate cell can be described as its own finite state machine. The finite state machines are determined by different sets of information.
The simplest CA is one dimensional with only two states for each cell. A cell and the cell on each side make up a neighborhood. These cells are the deciding factors as to what state is chosen for the element. Simple Cellular Automaton
Practical Uses of CA • For Rule 30, there has been thought that it could be used as a stream cipher for use in cryptography. CA has been used for public key cryptography. You can find the next state easily, but it is almost impossible to determine the last states. • Much more complex two dimensional cellular automaton has many uses, one of which is the evolution of population in an area. • Can also be a very interesting game
Creating Life • In the late 60’s and early 70’s, a man named James Conway created a two-dimensional CA called The Game of Life that popularized CA. The rules to Life are simple: • If a live cell has two or three live neighbors, it stays live • If a dead cell has three live neighbors it changes to live • For any other case, it becomes dead
The Evolution of Life for i = 1 to 100 for j = 1 to 100 s=0; for p = i-1 to i+1 for q = j-1 to j+1 s = s+L(p,q) s=s-L(i,j) if s = 3 or s+L(i,j) =3 X(i,j) = 1 else X(i,j) = 0 for i = 1 to 100 for j = 1 to 100 L(i,j) = X(i,j) display L(i,j)
The Evolution of Life(cont’d) • Conway originally believed that no population could grow without limit. • Every population would either die out or repeat a pattern. • Students at MIT proved this incorrect. • They created a glider gun which would emit a glider every 30 generations and in turn create an endlessly growing life.
Popularity of Life Life was a simple little game until Martin Gardner brought it to the attention of millions. He wrote a column in Popular Science about it and sparked the evolution of CA from a researching standpoint to the gaming aspect. Millions of technical minded people began playing The Game of Life.
Nowhere to Go Still Life Objects-Very common in Life are groups of cells that remain constant through the many steps of life.Some types of still life objects are blocks, beehives, boats, ships, and loafs. Block Ship Beehive Loaf Boat
Keep on Moving Oscillators-objects that change from step to step, but eventually repeat themselves. These include, but are not limited to, period 2 oscillators, including the blinker and the toad. Blinker Toad
Gliding Through Life Glider-A commonly found arrangement of cells (5 in total) that move themselves across a grid in the Game of Life Glider
A Little Lesson on Life Initial Setup After Pass 1 Number of Neighbors After Pass 2
Where Has Life Taken Us? Unfortunately for the computing society, after Conway released The Game of Life, most people did not look at CA the same way. CA became a source of entertainment instead of a science and it has not advanced much further than that of the days of Life
Summary • Cellular automaton has an old but brief history. • Simple cellular automaton is very easy and quite useful • Could have many beneficial qualities if researched and deveoped • Play The Game of Life, its fun and interesting
References • http://www.mirwoj.opus.chelm.pl/ca • http://www.brainyencyclopedia.com/encyclopedia/c/ce/cellular_automaton.html • http://www.frank-buss.de/automaton • http://www.hyperdictionary.com/dictionary/cellular+automaton • http://www.wordiq/defintion/Cellular_automaton • http://mathworld.wolfram.com/CellularAutomaton • http://computing-dictionary.thefreedictionary.com/cellular%20automaton • The New Turing Omnibus by A.K. Dewdney, ch. 44