nLab
axio-dilaton

Contents

Idea

In type IIB supergravity the dilaton/string coupling g sg_s and the degree-1 RR-field C 0C_0 of the D(-1)-brane combine into a complex function

τ:=C 0+ig 2 \tau := C_0 + i g_2

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

(a b c d):τaτ+bcτ+d. \left( \array{ a & b \\ c & d } \right) : \tau \mapsto \frac{a \tau + b}{c \tau + d} \,.

This combined field is also called the axio-dilaton.

Properties

Revised on May 7, 2014 23:26:03 by Urs Schreiber (88.128.80.30)