“We wanted the best, but it turned out as always.”
“Here is what can happen when somebody’s starting to reason”.
“Wine we need for health, and the health we need to drink vodka”.
Some sayings of Victor Chernomyrdin
In this chapter we begin by deriving the T duality perturbative symmetry of string theory from the world-sheet viewpoint in section 17.1. Although there is no complete formulation of string theory, the maximal supergravity theories in ten dimensions, studied in chapter 13, are the low energy effective actions for the type II strings. They are complete in that they contain all perturbative and all non-perturbative corrections. We will explain how these theories allow us to understand aspects of ...