nLab
axio-dilaton

Idea

In type IIB supergravity the dilaton/string coupling $g_{s}$ and the degree-1 RR-field $C_{0}$ combine into a complex function

τ : = C_{0} + i g_{2}

which transforms under the $SL (2, ℤ)$ S-duality $\subset$ U-duality as

(\begin{matrix} a & b \\ c & d \end{matrix}) : τ \mapsto \frac{a τ + b}{c τ + d} .

This combined field is also called the axio-dilaton.

In F-theory the variation of the axio-dilaton determines an elliptic fibration which encodes non-perturbative vacua of type IIB string theory.

Created on February 24, 2012 12:21:44 by Urs Schreiber (82.113.119.226)