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Elegant Universe, The: String's the Thing

Program Overview  Print this Teacher's Guide (PDF, 33 pages)

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Welcome to the 11th Dimension Program Overview

NOVA explores the evolution and features of string theory.

The program:

• reviews the concepts of general relativity (Einstein's theory of gravity that describes the universe on a large scale) and quantum mechanics (a theory that describes the universe on a very small scale) and the conflict between the two.

• discusses the breakdown of general relativity and quantum mechanics at the moment of the big bang, when the universe was both enormously massive and incredibly tiny.

• suggests that string theory may be able to unite the theories of general relativity and quantum mechanics, which would combine the four forces of nature—gravity, electromagnetism, the strong force, and the weak force—under one theory.

• describes the particles that comprise matter and relates how string theory proposes that the most elementary subatomic particles currently known may be made of strings.

• introduces the criticism that string theory cannot currently be tested experimentally or confirmed observationally.

• chronicles the development of string theory, including the theory's problems with mathematical inconsistencies, extra dimensions, and its prediction of an as-yet-unobserved massless particle (later theorized to be the graviton).

• reviews the development of the Standard Model, the experimentally verified theory that details elementary particles and their interactions, but does not include gravity.

• details the discovery of particles that carry the electromagnetic, the strong, and the weak forces and reviews the idea that these forces may have been unified at the earliest moments in time.

• explains how string theory evolved to provide a framework for understanding the four fundamental forces.

• reviews the basic concepts of string theory and how it resolves the conflict between general relativity and quantum theory.

• explains what dimensions are, explores the idea that string theory requires a universe with more than four spacetime dimensions, and proposes where these dimensions may exist.

• discusses the importance of the shape of the extra dimensions in determining the precise values of the fundamental components of the universe.

• highlights the dilemma string theorists faced in the late-1980s—that while searching for one theory of everything, they arrived at five different mathematically consistent, equally valid string theories.

For additional background information see:
The Science of Superstrings
Glossary