String Theories

Some articles on theories, string theories, string, strings:

Supergravity - History - The Second Superstring Revolution
... Initial excitement about the 10-dimensional theories, and the string theories that provide their quantum completion, died by the end of the 1980s ... theory beyond the regime of applicability of string perturbation theory ... For example, it became apparent that the various superstring theories were related by "string dualities", some of which relate weak string-coupling (i.e ...
String Duality
... String duality is a class of symmetries in physics that link different string theories, theories which assume that the fundamental building blocks of ... so-called "duality revolution" there were believed to be five distinct versions of string theory, plus the (unstable) bosonic and gluonic theories ... String Theories Type Spacetime dimensions Details Bosonic 26 Only bosons, no fermions means only forces, no matter, with both open and closed strings major flaw a particle with imaginary mass ...
String Theory - Basic Properties - Dualities
... Before the 1990s, string theorists believed there were five distinct superstring theories open type I, closed type I, closed type IIA, closed type IIB ... The thinking was that out of these five candidate theories, only one was the actual correct theory of everything, and that theory was the one whose low ... It is now believed that this picture was incorrect and that the five superstring theories are connected to one another as if they are each a special case ...
Superstring Theory - Number of Superstring Theories
... Theoretical physicists were troubled by the existence of five separate string theories ... the second superstring revolution in the 1990s, which suggests that the five string theories might be different limits of a single underlying theory, called M ... String theories Type Spacetime dimensions SUSY generators chiral open strings heterotic compactification gauge group tachyon Bosonic (closed) 26 N = 0 no no no none yes Bosonic (open) 26 N = 0 no yes no U(1 ...
String Theory - Basic Properties - Extra Dimensions - Number of Dimensions
... An intriguing feature of string theory is that it predicts extra dimensions ... In classical string theory the number of dimensions is not fixed by any consistency criterion ... to make a consistent quantum theory, string theory is required to live in a spacetime of the so-called "critical dimension" we must have 26 spacetime dimensions for the bosonic string and 10 for the ...

Famous quotes containing the words theories and/or string:

    Philosophers of science constantly discuss theories and representation of reality, but say almost nothing about experiment, technology, or the use of knowledge to alter the world. This is odd, because ‘experimental method’ used to be just another name for scientific method.... I hope [to] initiate a Back-to-Bacon movement, in which we attend more seriously to experimental science. Experimentation has a life of its own.
    Ian Hacking (b. 1936)

    Supposing everyone lived at one time what would they say. They would observe that stringing string beans is universal.
    Gertrude Stein (1874–1946)