Redefining Reality - The Intellectual Implications of Modern Science

Great press has been given to a potential TOE known as string
theory. It is an attempt not only to unify the electroweak
and strong forces but also to include a quantized picture
of gravitation. If true, it would give us a new image of
our universe.
Around the same time that Weyl was attempting to unify gravitation
proposed a picture that was subsequently developed by the Swedish
physicist Oskar Klein. According to the Kaluza-Klein model, we
Although it was later discarded, this multidimensional approach
came back in the 1970s as string theory. String theorists seem to
have come up with a way to account for all four forces if we think of
the points of space as small loops of string. These strings can move
in very different but independent ways, that is, they can vibrate or
spin in ways that do not affect other sorts of movements. If we think
of these independent motions of the string as dimensions, then we
have a rich Kaluza-Klein type model.
In 1995, Ed Witten showed that we can use these modes of string
vibrations to account for quantum and gravitational effects if
they have 11 distinct modes, that is, if we take reality to have 11
dimensions, 10 for space and 1 for time.
Some theorists have argued that we should not think of the points
of quantized space as strings but as two-dimensional surfaces,
like the head of a drum. Such surfaces could vibrate in much
more interesting and intricate ways. Space is, therefore, made of
membranes (branes), not strings.
drumhead membrane is degree 2. Others extended the idea to
take higher-degree membranes.
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