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Claude Shannon Essay, Research Paper

Overview

Noted

as a founder of information theory, Claude Shannon combined mathematical

theories with engineering principles to set the stage for the development

of the digital computer. The term ‘bit,’ today used to describe

individual units of information processed by a computer, was coined from

Shannon’s research in the 1940s.

A Midwesterner, Claude

Shannon was born in Gaylord, Michigan in 1916. From an early age, he showed

an affinity for both engineering and mathematics, and graduated from Michigan

University with degrees in both disciplines. For his advanced degrees,

he chose to attend the Massachusetts Institute of Technology.

At the time, MIT was

one of a number of prestigious institutions conducting research that would

eventually formulate the basis for what is now known as the information

sciences. Its faculty included mathematician Norbert Wiener, who would

later coin the term cybernetics to describe the work in information theories

that he, Shannon and other leading American mathematicians were conducting;

and Vannevar Bush, MIT’s dean of engineering, who in the early 1930s

had built an analog computer called the Differential Analyzer

The Differential Analyzer

was developed to calculate complex equations that tabulators and calculators

of the day were unable to address. It was a mechanical computer, using

a series of gears and shafts to engage cogs until the equation was solved.

Once it completed its cycle, the answer to the equation was obtained by

measuring the changes in position of its various machine parts. Its only

electrical parts were the motors used to drive the gears.

With its crude rods,

gears and axles, the analyzer looked like a child’s erector set.

Setting it up to work one equation could take two to three days; solving

the same equation could take equally as long, if not longer. In order

to work a new problem, the entire machine, which took up several hundred

feet of floor space, had to be torn apart and reset to a new mechanical

configuration.

While at MIT, Shannon

studied with both Wiener and Bush. Noted as a ‘tinkerer,’ he

was ideally suited to working on the Differential Analyzer, and would

set it up to run equations for other scientists. At Bush’s suggestion,

Shannon also studied the operation of the analyzer’s relay circuits

for his master’s thesis. This analysis formed the basis for Shannon’s

influential 1938 paper "A Symbolic Analysis of Relay and Switching

Circuits," in which he put forth his developing theories on the relationship

of symbolic logic to relay circuits. This paper, and the theories it contained,

would have a seminal impact on the development of information processing

machines and systems in the years to come.

Shannon’s paper

provided a glimpse into the future of information processing. While studying

the relay switches on the Differential Equalizer as they went about formulating

an equation, Shannon noted that the switches were always either open or

closed, or on and off. This led him to think about a mathematical way

to describe the open and closed states, and he recalled the logical theories

of mathematician George Boole, who in the middle 1800s advanced what he

called the logic of thought, in which all equations were reduced to a

binary system consisting of zeros and ones.

Boole’s theory,

which formulated the basis for Boolean algebra, stated that a statement

of logic carried a one if true and a zero if false. Shannon theorized

that a switch in the on position would equate to a Boolean one. In the

off position, it was a zero.

By reducing information

to a series of ones and zeros, Shannon wrote, information could be processed

by using on-off switches. He also suggested that these switches could

be connected in such a way to allow them to perform more complex equations

that would go beyond simple ‘yes’ and ‘no’ statements

to ‘and’, ‘or’ or ‘not’ operations.

Shannon graduated from

MIT in 1940 with both a master’s degree and doctorate in mathematics.

After graduation, he spent a year as a National Research Fellow at the

Institute for Advanced Study at Princeton University, where he worked

with mathematician and physicist Hermann Weyl. In 1941, Shannon joined

the Bell Telephone Laboratories, where he became a member of a group of

scientists charged with the tasks of developing more efficient information

transmitting methods and improving the reliability of long-distance telephone

and telegraph lines.

Shannon believed that

information was no different than any other quantity and therefore could

be manipulated by a machine. He applied his earlier research to the problem

at hand, again using Boolean logic to develop a model that reduced information

to its most simple form–a binary system of yes/no choices, which could

be presented by a 1/0 binary code. By applying set codes to information

as it was transmitted, the noise it picked up during transmission could

be minimized, thereby improving the quality of information transmission.

In the late 1940s,

Shannon’s research was presented in The Mathematical Theory of

Communications, which he co-authored with mathematician Warren Weaver.

It was in

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