Superspace Techniques for Superstring Theories.
Superspace techniques are used to calculate the critical dimensions of string theories, to give complete superspace descriptions of supergravity theories relevant to string theories, and to calculate the conformal anomaly for superstring theories in curved superspace backgrounds. A new technique is developed for projecting superspace Lagrangians to component Lagrangians. Critical dimensions for strings coupled to vector multiplets of N = 1 and N = 2 supergravities are calculated by reducing the superspace to unidextrous (1,0) superspace and applying previously known results for the anomalies of unidextrous supermultiplets. The main technique that is employed for the construction of supergravity theories is the solution of the Bianchi identities after imposition of appropriate constraints on the torsions and curvatures. Off-shell N = 2 and N = 4 extended supergravities in two dimensions, N = 1 and N = 2 supergravities in three dimensions, and on-shell N = 2a supergravity in ten dimensions are constructed in this way. The same technique is used to obtain generalized -Weyl-transformed versions of superconformal and 16-16 supergravities in four dimensions. Unconstrained prepotentials are found for three-dimensional N = 1 supergravity by imposing the constraints obtained from the Bianchi identities. These prepotentials allow quantization of the linearized theory by the superspace generalization of the Fadeev-Popov method. Superspace normal coordinate expansion is used to calculate the conformal anomaly for the superstring coupled to a ten-dimensional curved superspace background. The conformal anomaly is found to be non-vanishing for backgrounds with a non-vanishing dilatino field, when the effective action is calculated according to the ghost truncation method of Kallosh.
- Pub Date:
- December 1989
- Physics: Elementary Particles and High Energy