The interest in membranes and higher dimensional extended geometrical objects was inspired by the great successes of the string and superstring, first in 1968–73 as a theory of hadrons and then since 1984 as a “theory of everything” — a unified theory of all interactions, including quantum gravity. In particular, membranes, “supermembranes” and “spinning membranes” have been studied since 1985; an unexpected connection with supergravity opened in 1988 some new prospects for a quantized theory. General theorems about higher dimensional “p-branes” or “extendons” were also derived. The subject is very promising, whether as a more comprehensive fundamental unification or as a description of composite hadrons.Where there are now probably some fifty texts of all kinds dealing with strings, this is the first treatise on membranes and higher dimensional extendons.

The interest in membranes and higher dimensional extended geometrical objects was inspired by the great successes of the string and superstring, first in 1968–73 as a theory of hadrons and then since 1984 as a “theory of everything” — a unified theory of all interactions, including quantum gravity. In particular, membranes, “supermembranes” and “spinning membranes” have been studied since 1985; an unexpected connection with supergravity opened in 1988 some new prospects for a quantized theory. General theorems about higher dimensional “p-branes” or “extendons” were also derived. The subject is very promising, whether as a more comprehensive fundamental unification or as a description of composite hadrons.Where there are now probably some fifty texts of all kinds dealing with strings, this is the first treatise on membranes and higher dimensional extendons.

The interest in membranes and higher dimensional extended geometrical objects was inspired by the great successes of the string and superstring, first in 1968–73 as a theory of hadrons and then since 1984 as a “theory of everything” — a unified theory of all interactions, including quantum gravity. In particular, membranes, “supermembranes” and “spinning membranes” have been studied since 1985; an unexpected connection with supergravity opened in 1988 some new prospects for a quantized theory. General theorems about higher dimensional “p-branes” or “extendons” were also derived. The subject is very promising, whether as a more comprehensive fundamental unification or as a description of composite hadrons.Where there are now probably some fifty texts of all kinds dealing with strings, this is the first treatise on membranes and higher dimensional extendons.