Covariant Closed String Field Theory
Covariant closed string field theories are considerably more complicated than their open string cousins. Even if one wants to construct a string field theory which only reproduces tree-level interactions between closed strings, the classical action must contain an infinite number of vertices consisting of string polyhedra.
If one demands that on-shell scattering diagrams be reproduced to all orders in the string coupling, one must also include additional vertices arising from higher genus (and hence higher order in ) as well. In general, a manifestly BV invariant, quantizable action takes the form
where denotes an th order vertex arising from a genus surface and is the closed string coupling. The structure of the vertices is in principle determined by a minimal area prescription, although, even for the polyhedral vertices, explicit computations have only been performed to quintic order.
Read more about this topic: String Field Theory
Famous quotes containing the words closed, string, field and/or theory:
“One man’s observation is another man’s closed book or flight of fancy.”
—Willard Van Orman Quine (b. 1908)
“Amongst the learned the lawyers claim first place, the most self-satisfied class of people, as they roll their rock of Sisyphus and string together six hundred laws in the same breath, no matter whether relevant or not, piling up opinion on opinion and gloss on gloss to make their profession seem the most difficult of all. Anything which causes trouble has special merit in their eyes.”
—Desiderius Erasmus (c. 1466–1536)
“The poet will write for his peers alone. He will remember only that he saw truth and beauty from his position, and expect the time when a vision as broad shall overlook the same field as freely.”
—Henry David Thoreau (1817–1862)
“... the first reason for psychology’s failure to understand what people are and how they act, is that clinicians and psychiatrists, who are generally the theoreticians on these matters, have essentially made up myths without any evidence to support them; the second reason for psychology’s failure is that personality theory has looked for inner traits when it should have been looking for social context.”
—Naomi Weisstein (b. 1939)